Introduction: The effect of age on health outcomes in kidney transplantation remains inconclusive. This study aimed to analyze the relationship between age at time of kidney transplantation with mortality, graft loss and self-rated health status in adult kidney transplant recipients.

Methods: This study used data from the Swiss Transplant Cohort Study and included prospective data of kidney transplant recipients between 2008 and 2017. Time-to-event analysis was performed using Cox’ regression analysis, and -in the case of graft loss- competing risk analysis. A random-intercept regression model was applied to analyse self-rated health status.

Results: We included 2,366 kidney transplant recipients. Age at transplantation linearly predicted mortality. It was also predictive for graft loss, though nonlinearly, showing that recipients aged between 35 and 55 years presented with the lowest risk of experiencing graft loss. No relationship of age with self-rated health status was detected.

Conclusion: Higher mortality in older recipients complies with data from the general population. The non-linear relationship between age and graft loss and the higher scored self-rated health status at all follow-up time-points compared to the pre-transplant status -regardless of age- highlight that age alone might not be an accurate measure for risk prediction and clinical decision making in kidney transplantation.

Food-safety measures are recommended to solid organ transplant (SOT) recipients. However, the burden of foodborne infections in SOT recipients has not been established. We describe the epidemiology and outcomes of bacterial foodborne infections in a nationwide cohort including 4405 SOT recipients in Switzerland between 2008 and 2018. Participants were prospectively followed for a median of 4.2 years with systematic collection of data on infections, and patient and graft-related outcomes. We identified 151 episodes of microbiologically confirmed bacterial foodborne infections occurring in median 1.6 years (IQR 0.58–3.40) after transplantation (131 [88%] Campylobacter spp. and 15 [10%] non-typhoidal Salmonella). The cumulative incidence of bacterial foodborne infections was 4% (95% CI 3.4–4.8). Standardized incidence rates were 7.4 (95% CI 6.2–8.7) and 4.6 (95% CI 2.6–7.5) for Campylobacter and Salmonella infections, respectively. Invasive infection was more common with Salmonella (33.3% [5/15]) compared to Campylobacter (3.2% [4/125]; p = .001). Hospital and ICU admission rates were 47.7% (69/145) and 4.1% (6/145), respectively. A composite endpoint of acute rejection, graft loss, or death occurred within 30 days in 3.3% (5/151) of cases. In conclusion, in our cohort bacterial foodborne infections were late post-transplant infections and were associated with significant morbidity, supporting the need for implementation of food-safety recommendations.

AIMS: In Switzerland, certain patients with disabilities and reduced working ability are entitled to a disability pension granted by the Swiss Federal Social Insurance Office (FSIO). The aim was to assess the evolution of disability pension and work capacity after kidney transplantation and thereby pilot the procedures linking FSIO data with Swiss Transplant Cohort Study (STCS) data.

METHODS: The current study pilot tested the record linkage of FSIO data with data from the STCS in a singlecentre, observational setting. Patients were requested to consent to the use of their Swiss social security number (SSSN) for the purpose of record linkage. A privacy preserving trust centre approach was implemented with blinded statistical analysis.

RESULTS: Between May 2008 and December 2015, 282 working-age renal transplant recipients of the University Hospital of Basel transplant centre were eligible for inclusion and 136 (48%, median age 48 years) consented to the use of their social security number and record linkage. The FSIO datasets of all patients were successfully retrieved and linked to STCS data in the trust centre and were numerically analysable. Yearly FSIO allowance data were available for the entire study duration. Fifty-five patients (40%) were registered as disability insurance recipients (DIR). In the entire population, the proportion of working patients slightly decreased from 76% to 72% between the pre-transplant and the post-transplant period. This was due to the lower proportion of patients working after transplantation in DIR compared with non-recipients (non-DIR) (DIR: 60% before vs 44% after; non-DIR: 83% before vs 88% after). In the DIR group, the proportion of patients not working increased from 36% to 49%, whereas in non-DIR the proportion changed only marginally (14% to 12%). The average disability insurance allowance was CHF 1172 per month. It changed from CHF 1135 before transplantation to CHF 1209 after transplantation (p = 0.59).

CONCLUSIONS: In the Swiss healthcare and social insurance system, record linkage studies combining clinical datasets with data from FSIO are feasible but associated with great efforts and resource needs. The lack of changes in disability allowances after kidney transplantation should be further investigated in the nationwide setting.

ClinicalTrials.gov Number: NCT01204944

The aim of this study was to analyze first year renal outcomes in a nationwide prospective multicenter cohort comprising 2215 renal transplants, with a special emphasis on the presence of pre-transplant donor-specificHLA antibodies (DSA). All transplants had a complete virtual crossmatch and DSA were detected in 19% (411/2215). The investigated composite endpoint was a poor first-year outcome defined as (i) allograft failure or (ii) death or (iii) poor allograft function (eGFR ≤25 ml/min/1.73 m2) at one year. Two hundred and twenty-one (221/2215; 10%) transplants showed a poor first-year outcome. Rejection (24/70; 34%) was the most common reason for graft failure. First-year patient’s death was rare (48/ 2215; 2%). There were no statistically significant differences between DSA-positive and DSA-negative transplants regarding composite and each individual endpoint, as well as reasons for graft failure and death. DSA-positive transplants experienced more frequently rejection episodes, mainly antibody-mediated rejection (both P < 0.0001). The combination of DSA and any first year rejection was associated with the overall poorest deathcensored allograft survival (P < 0.0001). In conclusion, presence of pre-transplant DSA per se does not affect first year outcomes. However, DSA-positive transplants experiencing first year rejection are a high-risk population for poor allograft survival and may benefit from intense clinical surveillance.

Background: The burden and timeline of posttransplant infections are not comprehensively documented in the current era of immunosuppression and prophylaxis.

Methods: In this prospective study nested within the Swiss Transplant Cohort Study (STCS), all clinically relevant infections were identified by transplant-infectious diseases physicians in persons receiving solid organ transplant (SOT) between May 2008 and December 2014 with ≥12 months of follow-up.

Results: Among 3541 SOT recipients, 2761 (1612 kidney, 577 liver, 286 lung, 213 heart, and 73 kidney-pancreas) had ≥12 months of follow-up; 1520 patients (55%) suffered 3520 infections during the first year posttransplantation. Burden and timelines of clinically relevant infections differed between transplantations. Bacteria were responsible for 2202 infections (63%) prevailing throughout the year, with a predominance of Enterobacteriaceae (54%) as urinary pathogens in heart, lung, and kidney transplant recipients, and as digestive tract pathogens in liver transplant recipients. Enterococcus spp (20%) occurred as urinary tract pathogens in kidney transplant recipients and as digestive tract pathogens in liver transplant recipients, and Pseudomonas aeruginosa (9%) in lung transplant recipients. Among 1039 viral infections, herpesviruses predominated (51%) in kidney, liver, and heart transplant recipients. Among 263 fungal infections, Candida spp (60%) prevailed as digestive tract pathogens in liver transplant recipients. Opportunistic pathogens, including Aspergillus fumigatus (1.4%) and cytomegalovirus (6%), were rare, scattering over 12 months across all SOT recipients.

Conclusions: In the current era of immunosuppression and prophylaxis, SOT recipients experience a high burden of infections throughout the first year posttransplantation, with rare opportunistic pathogens and a predominance of bacteria.

Immunocompromised patients may be at increased risk for complications of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. However, comprehensive data of SARS-CoV-2 infection in solid organ transplant (SOT) recipients are still lacking. We performed a multicenter nationwide observational study within the Swiss Transplant Cohort Study (STCS) to describe the epidemiology, clinical presentation, treatment and outcomes of the first microbiologically documented SARS-CoV-2 infection among SOT recipients. Overall, 21 patients were included with a median age of 56 years (10 kidney, 5 liver, 1 pancreas, 1 lung, 1 heart and 3 combined transplantations). The most common presenting symptoms were fever (76%), dry cough (57%), nausea (33%) and diarrhea (33%). Ninety-five percent and 24% of patients required hospital and ICU admission, respectively, and 19% were intubated. After a median of 33 days of follow-up, 16 patients were discharged, 3 were still hospitalized and 2 patients died. These data suggest that clinical manifestations of SARS-CoV-2 infection in middle-aged SOT recipients appear to be similar to the general population without an apparent higher rate of complications. These results need to be confirmed in larger cohorts.

Background: Infections are an important complication after allogeneic hematopoietic cell transplantation (allo-HCT). The present study aimed at determining the landscape of infections occurring in a large cohort of allo-HCT patients, as well as associated risk factors for infections and for one-year non-relapse mortality.

Methods: This is a retrospective cohort study using STCS and EBMT databases to assess the one-year incidence rate of infection, as well as risk factors for infections and for one-year non-relapse mortality among adult allo-HCT patients transplanted between 2010 and 2014 in Switzerland. Univariable and multivariable quasi-Poisson and multivariable Cox regression models were used.

Results: Of 553 patients included, 486 had an infection with a global incidence rate of 3.66 infections per patient-year. Among a total of 1534 infections analyzed, viral infections were predominant (n = 1138, 74.2%), followed by bacterial (n = 343, 22.4%) and fungal (n = 53, 3.5%) infections. At one year, the cumulative incidence of relapse and non-relapse mortality was 26% and 16%, respectively. 195 (35.3%) of patients had at least one episode of severe graft-versus-host-disease (GvHD). A center effect was observed, and underlying disease, donor type, cytomegalovirus serological constellation, and GvHD were also associated with the incidence rate of infections. There was an increased risk for one-year non-relapse mortality associated with all pathogens, specifically within two months of infection, and this remained true beyond 2 months of a fungal infection.

Conclusion: Despite advances to limit infections in this population, they still occur in most allo-HCT patients with a major impact on survival at 1 year.

In a large multi-center contemporary 8-year cohort study, one third of allogeneic hematopoietic cell transplant recipients (allogeneic-HCT recipients) with Pseudomonas aeruginosa (PSA) infection developed a recurrent infection within 3 months. Antibiotic treatment duration of ≥14-days was the only significantly associated variable with reduced recurrence rates of PSA-infections in allogeneic-HCT recipients.

The relevance of vitamin D for infections after kidney transplantation is poorly defined. 25-OH vitamin D (25-OHD) levels of 135 kidney transplant recipients, enrolled in the Swiss Transplant Cohort Study, were determined peri-transplant and 6 months post-transplant. Logistic regression was used to address associations of 25-OHD and overall infections and bacterial infections, respectively. For the first 6 months post-transplant, 25-OHD peri-transplant, and for the second period (after 6 to 30 months post-transplant), 25-OHD at 6 months post-transplant was considered. Vitamin D deficiency was common peri-transplant and remained highly prevalent 6 months after transplantation despite frequent supplementation. Median 25-OHD levels increased from 12.0ng/ml (IQR 5.3-19.5) peri-transplant to 16.5ng/ml (IQR 10.6-22.6) 6 months post-transplant (P=0.005). We did not detect a significant association between 25-OHD and overall infections (adjusted odds ratio (aOR) 1.05, 95% confidence interval (95%CI) 0.44-2.51; aOR 0.67, 95%CI 0.31-1.43) or bacterial infections (aOR 0.79, 95%CI 0.32-1.96; aOR 0.79, 95%CI 0.35-1.75) for the first and second period. To conclude, at both time points vitamin D deficiency was observed in more than 50% of kidney recipients, albeit an increase in 25-OHD in the longitudinal course was observed. No significant association of 25-OHD and infections was detected.

Background:

HLA-specific memory B cells may contribute to the serum HLA antibody pool upon antigen re-exposure. The aim of this pilot study was to investigate the presence of concurrent donor-specific memory B cell-derived HLA antibodies (DSA-M) in renal allograft recipients with pretransplant donor-specific HLA antibodies (DSA) and its association with occurrence of antibody-mediated rejection (AMR) using a recently developed method.

Methods:

Twenty patients with Luminex single antigen bead (SAB) assay-defined DSA but negative complement-dependent cytotoxicity crossmatches were enrolled. Plasma samples and peripheral blood mononuclear cells (PBMC) were collected at 3 timepoints (pretransplant, month 6, month 12). We analyzed IgG-purified and concentrated culture supernatants from polyclonally activated PBMC using SAB assays and compared HLA antibody profiles with same day plasma results.

Results:

Plasma SAB analysis revealed 35 DSA in 20 patients pretransplant. DSA-M were detected in 9/20 (45%) patients and for 10/35 specificities (29%). While median mean fluorescence intensity (MFI) values of DSA with concurrent DSA-M (5877) were higher than those of DSA without DSA-M (1476), 3/6 patients with AMR and low MFI DSA (<3000) had DSA-M. Overall, pretransplant DSA/DSA-M_pos allograft recipients showed a higher incidence of biopsy-proven (sub)clinical AMR (p=0.032) and a higher extent (g≥1+ptc≥1) of microvascular inflammation (67% versus 9%, p=0.02). In 17 patients (28 DSA) with posttransplant analyses, persisting DSA posttransplant had more often DSA-M (6/12; 50%) than nonpersisting DSA (2/16; 13%).

Conclusion:

Assessment of DSA-M might be a novel tool to supplement serum HLA antibody analysis for pretransplant risk stratification in patients with DSA.

New Onset Diabetes after Transplantation (NODAT) is a frequent complication after solid organ transplantation, with higher incidence during the first year. Several clinical and genetic factors have been described as risk factors of Type 2 Diabetes (T2DM). Additionally, T2DM shares some genetic factors with NODAT. We investigated if three genetic risk scores (w-GRS) and clinical factors were associated with NODAT and how they predicted NODAT development 1 year after transplantation. In both main (n = 725) and replication (n = 156) samples the clinical risk score was significantly associated with NODAT (ORmain : 1.60 [1.36-1.90], p = 3.72*10(-8) and ORreplication : 2.14 [1.39-3.41], p = 0.0008, respectively). Two w-GRS were significantly associated with NODAT in the main sample (ORw-GRS 2:1.09 [1.04-1.15], p = 0.001 and ORw-GRS 3 :1.14 [1.01-1.29], p = 0.03) and a similar ORw-GRS (2) was found in the replication sample, although it did not reach significance probably due to a power issue. Despite the low OR of w-GRS on NODAT compared to clinical covariates, when integrating w-GRS 2 and w-GRS 3 in the clinical model, the Area under the Receiver Operating Characteristics curve (AUROC), specificity, sensitivity and accuracy were 0.69, 0.71, 0.58 and 0.68, respectively, with significant Likelihood Ratio test discrimination index (p-value 0.0004), performing better in NODAT discrimination than the clinical model alone. Twenty-five patients needed to be genotyped in order to detect one misclassified case that would have developed NODAT 1 year after transplantation if using only clinical covariates. To our knowledge, this is the first study extensively examining genetic risk scores contributing to NODAT development.

New&dash;onset diabetes mellitus after transplantation (NODAT) is a complication following solid organ transplantation (SOT) and may be related to immune or inflammatory responses. We investigated whether single nucleotide polymorphisms (SNPs) within 158 immune&dash; or inflammation&dash;related genes contribute to NODAT in SOT recipients. The association between 263 SNPs and NODAT was investigated in a discovery sample of SOT recipients from the Swiss Transplant Cohort Study (STCS, n₁ = 696). Positive results were tested in a first STCS replication sample (n₂ = 489) and SNPs remaining significant after multiple test corrections were tested in a second SOT replication sample (n₃ = 156). Associations with diabetic traits were further tested in several large general population&dash;based samples (n > 480 000). Only SP110 rs2114592C>T remained associated with NODAT in the STCS replication sample. Carriers of rs2114592&dash;TT had 9.9 times (95% confidence interval [CI]: 3.22&dash;30.5, P = .00006) higher risk for NODAT in the combined STCS samples (n = 1184). rs2114592C>T was further associated with NODAT in the second SOT sample (odds ratio: 4.8, 95% CI: 1.55&dash;14.6, P = .006). On the other hand, SP110 rs2114592C>T was not associated with diabetic traits in population&dash;based samples, suggesting a specific gene&dash;environment interaction, possibly due to the use of specific medications (ie, immunosuppressants) in transplant patients and/or to the illness that may unmask the gene effect.

BACKGROUND: Lung transplantation (LTx) provides a viable option for the survival of end-stage lung diseases. Besides survival as a clinical outcome measure, health-related quality of life (HRQoL) and psychological distress have become important outcomes in studies investigating the effectiveness of LTx in the short-and long-term.OBJECTIVE: To assess and compare HRQoL trajectories of patients after LTx prior to and over a follow-up period of three years post-transplant, and to identify differences regarding distress, HRQoL and patient-related outcomes.METHODS: In this longitudinal study, 27 lung transplant recipients were prospectively examined for psychological distress (Symptom Checklist short version-9; SCL-K-9), health-related quality of life (EuroQOL five dimensions questionnaire; EQ-5D), depression (HADS-Depression scale), and socio-demographic and medical outcomes at two weeks, three months, six months and three years following LTx. Additionally, potential outcome-related predictors for LTx-outcomes at three years post-transplant were assessed. Data were collected in accordance with guidelines set by the STROBE (strengthening the reporting of observational studies in epidemiology) statement.RESULTS: Lung transplant recipients showed the most pronounced improvements in HRQoL and reduction in psychological distress between two weeks and three months post-transplant, with relative stable HRQoL and distress trajectories thereafter. The most important predictors of poor somatic health trajectories over time were the pre-transplant disease severity score and the pre-transplant HADS-Depression score. In addition, idiopathic pulmonary fibrosis (IPF) and pre-transplant extracorporeal membrane oxygenation (ECMO)-use predicted poorer survival, while cystic fibrosis was associated with better survival three years post-transplant.COMCLUSION: Lung transplantation yields significant survival and HRQoL benefits, with its peak improvement at three months post-transplant. The majority of patients can preserve these health changes in the long-term. Patients with a worse HRQoL and higher psychological distress at six months post-transplant tended to have a poorer survival post-transplant. Other risk factors for poorer survival included IPF, pre-transplant ECMO-use, pre-transplant symptoms of depression, high pre-transplant disease severity and worse somatic disease severity trajectories. The majority of LTx-recipients were unable to work due to illness-related reasons.

BACKGROUND: Limited published data exist on outcomes related to heart and/or lung transplantation in human immunodeficiency virus (HIV)-infected individuals.METHODS: We conducted a multicenter retrospective study of heart and lung transplantation in HIV-infected patients and describe key transplant- and HIV-related outcomes.RESULTS: We identified 29 HIV-infected thoracic transplant recipients (21 heart, 7 lung, and 1 heart and/or lung) across 14 transplant centers from 2000 through 2016. Compared with an International Society for Heart and Lung Transplantation registry cohort, we demonstrated similar 1-, 3-, and 5-year patient and allograft survivals for each organ type with a median follow up of 1,064 (range, 184-3,745) days for heart and 1,540 (range, 116-3,206) days for lung recipients. At 1 year, significant rejection rates were high (62%) for heart transplant recipients (HTRs). Risk factors for rejection were inconclusive, likely because of small numbers, but may be related to cautious early immunosuppression and infrequent use of induction therapy. Pulmonary bacterial infections were high (86%) for lung transplant recipients (LTRs). Median CD4 counts changed from baseline to 1 year from 399 to 411 cells/mu l for HTRs and 638 to 280 cells/mu l for LTRs. Acquired immunodeficiency syndrome-related events, including infections and malignancies, were rare. Rates of severe renal dysfunction suggest a need to modify nephrotoxic anti-retrovirals and/or immunosuppressants.CONCLUSIONS: HIV-infected HTRs and LTRs have similar survival rates to their HIV-uninfected counterparts. Although optimal immunosuppression is not defined, it should be at least as aggressive as that for HIV-uninfected recipients. Such data may help pave the way for the use of hearts and lungs from HIV-infected donors in HIV-infected recipients through HIV Organ Policy Equity Act protocols. (C) 2019 International Society for Heart and Lung Transplantation. All rights reserved.

Objectives: Because commensal viruses are defined by the immunologic tolerance afforded to them, any immunomodulation, such as is received during haematopoietic stem-cell transplantation, may shift the demarcation between innocuous viral resident and disease-causing pathogen.

Methods: We analysed by deep-sequencing the plasma virome of 40 allogeneic haematopoietic stem-cell transplantation patients 1 month after transplantation. Because human pegivirus (HPgV) was highly prevalent, we performed a 1-year screening of 122 plasma samples by specific real-time reverse transcription PCR assay. We used the log-rank test and the Gray test to assess association with outcomes, and the Mann-Whitney test and multivariable linear regression model to assess association with T-cell reconstitution.
Results: Polyomaviruses (PyV) (20/40 patients), anelloviruses (16/40), pegiviruses (14/40) and herpesviruses (14/40) were most frequently identified, including ten cytomegalovirus; three Epstein-Barr virus; two herpes simplex virus type 1; one human herpesvirus 6b and one human herpesvirus 7; 18 Merkel cell-PyV; two BK-PyV; three PyV-6; and one JC-PyV. Papillomavirus and adenovirus were identified in 11 and two patients, respectively. The HPgV specific real-time reverse transcription PCR screening identified 51 of 122 positive samples, high virus loads and persistent infections up to 1 year after transplantation. Comparison between patients with or without HPgV infection at time of transplantation did not reveal a significant difference in infections, engraftment, survival, graft vs. host disease, relapse or immune reconstitution.
Conclusions: The blood virome after allogeneic haematopoietic stem-cell transplantation includes several DNA viruses, notably herpesviruses and PyV. Among RNA viruses, HPgV is highly prevalent and persists for several months, and it thus may deserve special attention in further research on immune reconstitution. (C) 2018 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

OBJECTIVES: To investigate differences in chest computed tomography (CT) and chest radiographs (CXRs) of Pneumocystis jirovecii pneumonia (PJP) between renal transplant recipients (RTRs) and human immunodeficiency virus (HIV)-positive patients.METHODS: From 2005 to 2012, 84 patients with PJP (RTR n = 24; HIV n = 60) were included in this retrospective multicentre study. Written informed consent was obtained. CT scans and CXRs were recorded within 2 weeks after the onset of symptoms. PJP diagnosis was confirmed either by cytology/histology or successful empirical treatment. Two blinded radiologists analysed the conventional chest films and CT images, and recorded the radiological lung parenchyma patterns, lymph node enlargement and pleural pathologies (pneumothorax, effusion). The radiological features of the two subgroups were compared.RESULTS: Consolidations and solid nodules prevailed on CT in RTRs (91.7 +/- 5.6% vs 58.3 +/- 6.4% with HIV, p = 0.019 and 91.7 +/- 5.6% vs 51.6 +/- 6.5% with HIV, p = 0.005). HIV-positive patients with PJP showed more atelectasis (41.7 +/- 6.4% vs 4.2 +/- 4.1% in RTRs, p = 0.017) and hilar lymph node enlargement (23.3 +/- 5.5% vs 0.0 +/- 0.0% in RTRs, p = 0.088). Ground glass opacification was found in all cases. Pneumothorax was a rare complication, occurring in 3% of the HIV-positive patients; no pneumothorax was found in the RTRs. On CXR, the basal lungs were more affected in HIV-positive patients as compared with RTRs (p = 0.024).CONCLUSIONS: PJP on CT differs substantially between RTRs and HIV-positive patients. Physicians should be aware of such differences in order not to delay treatment, particularly in renal transplant recipients.

Allergy transfer upon solid organ transplantation has been reported in the literature, although only few data are available as to the frequency, significance, and management of these cases. Based on a review of 577 consecutive deceased donors from the Swisstransplant Donor-Registry, 3 cases (0.5%) of fatal anaphylaxis were identified, 2 because of peanut and 1 of wasp allergy. The sera of all 3 donors and their 10 paired recipients, prospectively collected before and after transplantation for the Swiss Transplant Cohort Study, were retrospectively processed using a commercial protein microarray fluorescent test. As early as 5 days posttransplantation, newly acquired peanut-specific IgE were transiently detected from 1 donor to 3 recipients, of whom 1 liver and lung recipients developed grade III anaphylaxis. Yet, to define how allergy testing should be performed in transplant recipients and to better understand the impact of immunosuppressive therapy on IgE sensitization, we prospectively studied 5 atopic living-donor kidney recipients. All pollen-specific IgE and >90% of skin prick tests remained positive 7 days and 3 months after transplantation, indicating that early diagnosis of donor-derived IgE sensitization is possible. Importantly, we propose recommendations with respect to safety for recipients undergoing solid-organ transplantation from donors with a history of fatal anaphylaxis.

Background Return to work with or after a chronic disease is not a very well understood process, influenced by a variety of personal, professional, societal and medical factors. The aim of this study is to identify predictors for return to work 12 months after a solid organ transplant applying a bio-psycho-social model.

Methods This study is based on patients included in the Swiss Transplant Cohort Study, a national prospective multicentre cohort, who underwent a first solid organ transplant (kidney, liver, heart, lung). Bio-psycho-social factors were tested and predictors of return to work identified using logistic regression models.

Results Among the 636 patients included in the study, 49.8% (317) were employed 12 months post-transplant. The major predictor for returning to work 12 months posttransplant was pre-transplant employment status (OR 10.8). Accordingly, the population was stratified in employed and not employed pre-transplant groups. Age, self-perceived health (6 months post-transplant) and the transplanted organ were significantly associated with post-transplant employment status in both groups. Return to work was influenced by education, depression (6 month post-transplant) and waiting time in the employed pre-transplant group and by invalidity pension in the not employed pre-transplant group.

Conclusion Employment status pre-transplant being highly associated with employment status post-transplant, the process promoting return to work should be started well before surgery. Biomedical, psychological and social factors must be taken into account to promote return to work in transplanted patients.

In solid organ transplant recipients (sOTRs), 5 years after transplantation cancer is a relevant cause of death. We aimed to report cancer incidence in the Swiss Transplant Cohort Study (STCS) between 2008 and 2014 and conducted a prospective cohort study of kidney, heart, lung, pancreas and liver transplant recipients enrolled into the STCS by retrospective analysis of collected data. The STCS provided data on 2758 solid organ transplants. In total, 134 cases of cancer were observed (30 liver, 21 prostate, 18 lung, 13 kidney, 52 other cancers). Standardised incidence ratios (SIRs) were highest for liver cancer, kidney cancer, thyroid cancer, gastric cancer, bladder cancer, cancer of the oral cavity and the pharynx and for lung cancer. Cancer occurrence differed according to the transplanted organ. Cancers were mainly diagnosed at World Health Organisation (WHO) stages I and IV. Treatment received was mainly surgery and, in some cases, included also radiation and/or chemotherapy. Bladder, kidney, liver, lung and prostate cancer were detected at a younger age compared with the general population. Cumulative hazards for death were increased for transplant recipients with cancer. Solid organ transplant recipients show an organ specific increase of cancer compared with the general Swiss population

Increasing evidence indicates a role of vitamin D in the immune system affecting response to infections. We aimed to characterize the role of vitamin D status, i.e. deficiency [25&dash;OH vitamin D (25&dash;OHD) <50 nmol/l] and no deficiency (25&dash;OHD ≥50 nmol/l) in incident infections after liver transplantation. In 135 liver transplant recipients, blood samples drawn at time of liver transplantation and 6 months afterwards were used to determine 25&dash;OHD levels. Incident infections episodes were prospectively collected within the Swiss Transplant Cohort Study database. Poisson regression was applied to address associations between vitamin D status and incident infections. Vitamin D deficiency was common at time of transplantation and 6 months afterwards without a significant change in median 25&dash;OHD levels. In univariable analyses, vitamin D deficiency was a risk factor for incident infections in the first 6 months post&dash;transplant incidence rate ratio (IRR 1.52, 95% CI 1.08–2.15, P = 0.018) and for bacterial infections occurring after 6 up to 30 months post&dash;transplant (IRR 2.29, 95% CI 1.06–4.94, P = 0.034). These associations were not detectable in multivariable analysis with adjustment for multiple confounders. Efforts to optimize vitamin D supplementation in liver transplant recipients are needed. Our data question the role of vitamin D deficiency in incident infections.

Bone disease contributes to relevant morbidity after solid organ transplantation. Vitamin D has a crucial role for bone metabolism. Activation of vitamin D depends on the endocrine function of both, liver and kidney. Our study assessed key markers of bone metabolism at time of transplantation and 6 months after transplantation among 70 kidney and 70 liver recipients. In 70 kidney recipients 25-OH vitamin D levels did not differ significantly between peri-transplant (median 32.5nmol/l) and 6 months post-transplant (median 41.9nmol/l; P = 0.272). Six months post-transplant median 1, 25-(OH)(2) vitamin D levels increased by >300% (from 9.1 to 36.5ng/l; P<0.001) and median intact parathyroid hormone levels decreased by 68.4% (from 208.7 to 66.0 ng/l; P<0.001). Median 6-Crosslaps (CTx) and total procollagen type 1 amino-terminal propeptide (P1NP) decreased by 65.1% (from 1.32 to 0.46ng/ml; P<0.001) and 60.6% (from 158.2 to 62.3ng/ml; P<0.001), respectively. Kidney recipients with incident fractures had significantly lower levels of 1, 25-(OH)(2) vitamin D at time of transplantation and of intact parathyroid hormone 6 months post-transplant. Among 70 liver recipients, 25-OH vitamin D, 1, 25-(OH)(2) vitamin D and intact parathyroid hormone levels were not significantly altered between peri-transplant and 6 months post-transplant. Contrary to kidney recipients, median CTx increased by 60.0% (from 0.45 to 0.72 ng/ml; P = 0.002) and P1NP by 49.3% (from 84.0 to 125.4ng/ml; P = 0.001) in the longitudinal course. Assessed biomarkers didn't differ between liver recipients with and without fractures. To conclude, the assessed panel of biomarkers proved highly dynamic after liver as well as kidney transplantation in the early post-transplant period. After kidney transplantation a significant gain in 1, 25-(OH)(2) vitamin D combined with a decline in iPTH, CTx and P1 NP, whereas after liver transplantation an increase in CTx and P1 NP were characteristic.

Clostridium difficile infection (CDI) is a leading cause of infectious diarrhea in solid organ transplant recipients (SOT). We aimed to assess incidence, risk factors, and outcome of CDI within the Swiss Transplant Cohort Study (STCS). We performed a case&dash;control study of SOT recipients in the STCS diagnosed with CDI between May 2008 and August 2013. We matched 2 control subjects per case by age at transplantation, sex, and transplanted organ. A multivariable analysis was performed using conditional logistic regression to identify risk factors and evaluate outcome of CDI. Two thousand one hundred fifty&dash;eight SOT recipients, comprising 87 cases of CDI and 174 matched controls were included. The overall CDI rate per 10 000 patient days was 0.47 (95% confidence interval ([CI] 0.38&dash;0.58), with the highest rate in lung (1.48, 95% CI 0.93&dash;2.24). In multivariable analysis, proven infections (hazard ratio [HR] 2.82, 95% CI 1.29&dash;6.19) and antibiotic treatments (HR 4.51, 95% CI 2.03&dash;10.0) during the preceding 3 months were independently associated with the development of CDI. Despite mild clinical presentations, recipients acquiring CDI posttransplantation had an increased risk of graft loss (HR 2.24, 95% CI 1.15&dash;4.37; P = .02). These findings may help to improve the management of SOT recipients.

Background There is lack of recent multicenter epidemiological data on invasive aspergillosis (IA) among solid organ transplant recipient (SOTr) in the mold-acting antifungal era. We describe the epidemiology and outcomes of IA in a contemporary cohort of SOTr using the Swiss Transplant Cohort Study.
Methods All consecutive SOTr with proven or probable IA between 01.05.2008 and 31.12.2014 were included. A case-control study to identify IA predictors was performed: 1-case was matched with 3-controls based on SOT type, transplant center, and time post-SOT.
Results Among 2868 SOTr, 70 (2.4%) patients were diagnosed with proven (N:30/70, 42.9%) or probable (N: 40/70, 57.1%) IA. The incidence of IA was 8.3%, 7.1%, 2.6%, 1.3%, and 1.2% in lung, heart, combined, kidney, and liver transplant recipients, respectively, Galactomannan immunoassay was positive in 1/3 of patients tested. Only 33/63 (52.4%) of patients presented with typical pulmonary radiographic findings. Predictors of IA included: renal insufficiency, re-operation, and bacterial and viral infections. 12-week mortality was higher in liver (85.7%, 6/7) compared to other (15.9%, 10/63; P<.001) SOTr.
Conclusions Invasive aspergillosis remains a rare complication post-SOT, with atypical radiographic presentations and low positivity rates of biomarkers posing significant diagnostic challenges. Although overall mortality has decreased in SOTr, it remains high in liver SOTr.

Contemporary, comprehensive data on epidemiology and outcomes of invasive fungal disease (IFD) including breakthrough IFD among allogeneic hematopoietic stem cell transplantation (HSCT) recipients are scarce. We included 479 allogeneic HSCT recipients with 10 invasive candidiasis (IC) and 31 probable/proven invasive mold disease (IMD) from the Swiss Transplant Cohort Study from 01.2009 to 08.2013. Overall cumulative incidence was 2.3% for IC and 8.5% for probable/proven IMI: 6% for invasive aspergillosis (IA) and 2.5% for non-Aspergillus IMI. Among 41 IFD, 46% IFD were breakthrough, with an overall incidence of 4.6%, more frequently caused by other-than-Aspergillus fumigatus molds than primary IFD (47.6% (10/21) vs 13% (3/23), P = 0.04). Twelve-week mortality among patients with IC was 20% and 58.6% for probable/proven IMD (60% IA and 54.6% non-Aspergillus). Our results reveal that breakthrough IFD represent a marked burden of probable/proven IFD postallogeneic HSCT and mortality remains above 50% in patients with probable/proven IMD, underscoring the ongoing challenges to prevent and treat IFD in these patients.

UL18 is a human CMV (HCMV) MHC class I (MHCI) homolog that efficiently inhibits leukocyte immunoglobulin-like receptor subfamily B member 1 (LILRB1)⁺ NK cells. We found an association of LILRB1 polymorphisms in the regulatory regions and ligand-binding domains with control of HCMV in transplant patients. Naturally occurring LILRB1 variants expressed in model NK cells showed functional differences with UL18 and classical MHCI, but not with HLA-G. The altered functional recognition was recapitulated in binding assays with the binding domains of LILRB1. Each of 4 nonsynonymous substitutions in the first 2 LILRB1 immunoglobulin domains contributed to binding with UL18, classical MHCI, and HLA-G. One of the polymorphisms controlled addition of an N-linked glycan, and that mutation of the glycosylation site altered binding to all ligands tested, including enhancing binding to UL18. Together, these findings indicate that specific LILRB1 alleles that allow for superior immune evasion by HCMV are restricted by mutations that limit LILRB1 expression selectively on NK cells. The polymorphisms also maintained an appropriate interaction with HLA-G, fitting with a principal role of LILRB1 in fetal tolerance.

BACKGROUND: Post-transplant lymphoproliferative disorder (PTLD) is a potentially life-threatening complication of transplantation occurring in the setting of immunosuppression and oncogenic viral infections. However, little is known about the cumulative incidence, histological subtypes, risk determinants and outcome of PTLD in solid organ transplant (SOT) recipients in Switzerland.METHODS: This retrospective observational study investigated adult SOT recipients from two sequential cohorts, the pre-SCTS (Swiss Transplant Cohort Study) series, with data collected from January 1986 to April 2008, and the STCS series, with data collected from May 2008 to December 2014 in Switzerland. SOT recipients were cross-referenced with the data of all the patients with a lymphoma diagnosis in each transplant centre and with the data of the Swiss Transplant Cohort Study (STCS) to determine the cumulative incidence of PTLD, pre-therapeutic clinical features, clinical course and outcome. Kaplan-Meier analysis was performed for overall survival after PTLD.RESULTS: We identified 79 cases of PTLD during the study period in the two cohorts: pre-STCS from 1986 to 2008 (n = 62) and STCS from 2008 to 2014 (n = 17). Histological subgroups included: early lesions (pre-STCS n = 2, STCS n = 0); polymorphic PTLD (pre-STCS n = 8, STCS n = 7); monomorphic PTLD (pre-STCS n = 47, STCS n = 10), and Hodgkin's lymphoma (pre-STCS n = 5, STCS n = 0). Median time to PTLD diagnosis was 90 months (range 3-281 months) and 14 months (range 2-59 months) in the pre-STCS and STCS cohorts, respectively. Median follow-up after transplantation was 141 months for the pre-STCS patients and 33 months for the STCS patients. Cumulative incidences of PTLD during the STCS period at 0.5, 1 and 5 years were 0.17% (95% confidence interval 0.07-0.46%), 0.22% (0.09-0.53%) and 0.96% (0.52-1.80%), respectively. For the pre-STCS case series, it was not possible to estimate the incidence rate of PTLD. Survival after PTLD diagnosis was 80% (68-87%) at 1 year and 56% (42-68%) at 5 years for the pre-STCS and STCS cohorts combined.CONCLUSIONS: At 5 years, the cumulative incidence of PTLD, regardless of the organ transplanted, was only 0.96% in the STCS cohort, which is lower than that reported in the literature.

Objectives: To assess the risk factors for development of late-onset invasive pulmonary aspergillosis (IPA) after kidney transplantation (KT).Methods: We performed a multinational case-control study that retrospectively recruited 112 KT recipients diagnosed with IPA between 2000 and 2013. Controls were matched (1:1 ratio) by centre and date of transplantation. Immunosuppression-related events (IREs) included the occurrence of non-ventilator-associated pneumonia, tuberculosis, cytomegalovirus disease, and/or de novo malignancy.Results: We identified 61 cases of late (> 180 days after transplantation) IPA from 24 participating centres (accounting for 54.5% (61/112) of all cases included in the overall study). Most diagnoses (54.1% (33/61)) were established within the first 36 post-transplant months, although five cases occurred more than 10 years after transplantation. Overall mortality among cases was 47.5% (29/61). Compared with controls, cases were significantly older (p 0.010) and more likely to have pre-transplant chronic obstructive pulmonary disease (p 0.001) and a diagnosis of bloodstream infection (p 0.016) and IRE (p < 0.001) within the 6 months prior to the onset of late IPA. After multivariate adjustment, previous occurrence of IRE (OR 19.26; 95% CI 2.07-179.46; p 0.009) was identified as an independent risk factor for late IPA.Conclusion: More than half of IPA cases after KT occur beyond the sixth month, with some of them presenting very late. Late IPA entails a poor prognosis. We identified some risk factors that could help the clinician to delimit the subgroup of KT recipients at the highest risk for late IPA. (c) 2017 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Weight gain after liver transplantation (LTx) facilitates development of new&dash;onset obesity; however, its risk factors and outcomes are poorly understood. We identified the impact of new&dash;onset obesity on cardiovascular events (CVEs) and patient survival, and risk factors for new&dash;onset obesity. Multiple Cox regression models examined risk factors for CVEs, patient survival, and new&dash;onset obesity in 253 adults (mean age 52.2 ± 11.6 years, male gender 63.6%, mean follow up 5.7 ± 2.1 years). Cumulative incidence of post&dash;LTx CVE was 28.1%; that of new&dash;onset obesity was 21.3%. Regardless of CVE at LTx, post&dash;LTx CVEs were predicted by new&dash;onset obesity [Hazard Ratio (HR), 2.95; P = 0.002] and higher age at LTx (HR, 1.05; P < 0.001). In patients without known pre&dash;LTx CVEs (n = 214), risk factors for post&dash;LTx CVEs were new&dash;onset obesity (HR, 2.59; P = 0.014) and higher age (HR, 1.04; P = 0.001). Survival was not associated with new&dash;onset obesity (P = 0.696). Alcoholic liver disease predicted new&dash;onset obesity (HR, 3.37; P = 0.025), female gender was protective (HR, 0.39; P = 0.034). In 114 patients with available genetic data, alcoholic liver disease (HR, 12.82; P = 0.014) and hepatocellular carcinoma (HR, 10.02; P = 0.048) predicted new&dash;onset obesity, and genetics remained borderline significant (HR, 1.07; P = 0.071). Early introduction of post&dash;LTx weight management programs may suggest a potential pathway to reduce CVE risk.

Background: Descriptive data on Pneumocystis jirovecii pneumonia (PJP) in solid organ transplant recipients (SOTr) in the era of routine Pneumocystis-prophylaxis are lacking.

Methods: All adult SOTr between 2008 and 2016 were included. PJP was diagnosed based on consensus guidelines. Early-onset PJP was defined as PJP within the first-year-post-transplant.
Results: 41/2842 SOTr (1.4%) developed PJP (incidence rate: 0.01/1000 persondays) at a mean of 493-days post-transplant: 21 (51.2%) early vs 20 (48.8%) lateonset PJP. 2465 (86.7%) SOTr received Pneumocystis-prophylaxis for a mean 316 days. PJP incidence was 0.001% and 0.003% (log-rank < 0.001) in SOTr with and without Pneumocystis-prophylaxis, respectively. PJP was an early event in 10/12 (83.3%) SOTr who did not receive Pneumocystis-prophylaxis and developed PJP, compared to those patients who received prophylaxis (11/29, 37.9%; P-value: 0.008). Among late-onset PJP patients, most cases (13/20, 65%) were observed during the 2nd year post-transplant. Age >= 65 years (OR: 2.4, P-value: 0.03) and CMV infection during the first 6 months post-SOT (OR: 2.5, P-value: 0.006) were significant PJP predictors, while Pneumocystis-prophylaxis was protective for PJP (OR: 0.3, P-value: 0.006) in the overall population. Most patients (35, 85.4%) were treated with trimethoprim-sulfamethoxazole for a mean 20.6 days. 1-year mortality was 14.6%.
Conclusions: In the Pneumocystis-prophylaxis-era, PJP remains a rare post-transplant complication. Most cases occurred post-PJP-prophylaxis-discontinuation, particularly during the second-year-post-transplant. Additional research may help identify indications for Pneumocystis-prophylaxis prolongation.

BK polyomavirus (BKPyV ) causes premature kidney transplant (KT ) failure in 1–15% of patients. Because antivirals are lacking, most programs screen for BKPyV &dash;viremia and, if positive, reduce immunosuppression. To evaluate the relationship of viremia and BKPyV &dash;specific immunity, we examined prospectively cryopreserved plasma and peripheral blood mononuclear cells at the time of transplantation (T0) and at 6 mo (T6) and 12 mo (T12) after transplant from 28 viremic KT patients and 68 nonviremic controls matched for the transplantation period. BKPyV IgG seroprevalence was comparable between cases (89.3%) and controls (91.2%; p = 0.8635), but cases had lower antibody levels (p = 0.022) at T0. Antibody levels increased at T6 and T12 but were not correlated with viremia clearance. BKPyV &dash;specific T cell responses to pools of overlapping 15mers (15mer peptide pool [15mP]) or immunodominant CD 8 9mers (9mer peptide pool [9mP]) from the early viral gene region were not different between cases and controls at T0; however, clearance of viremia was associated with stronger 9mP responses at T6 (p = 0.042) and T12 (p = 0.048), whereas 15mP responses were not informative (T6 p = 0.359; T12 p = 0.856). BKPyV &dash;specific T cells could be expanded in vitro from all patients after transplant, permitting identification of 78 immunodominant 9mer epitopes including 50 new ones across different HLA class I. Thus, 9mP&dash;responses may be a novel marker of reconstituting CD 8 T cell function that warrants further study as a complement of plasma BKPyV loads for guiding immunosuppression reduction.

Background: Poor sleep quality (SQ) is common after solid organ transplantation; however, very little is known about its natural history. We assessed the changes in SQ from pre- to 3 years post-transplant in adult heart, kidney, liver and lung recipients included in the prospective nationwide Swiss Transplant Cohort Study. We explored associations with selected variables in patients suffering persistent poor SQ compared to those with good or variable SQ.

Methods: Adult single organ transplant recipients enrolled in the Swiss Transplant Cohort Study with pre-transplant and at least 3 post-transplant SQ assessment data were included. SQ was self-reported pre-transplant (at listing), then at 6, 12, 24 and 36 months post-transplant. A single SQ item was used to identify poor (0-5) and good sleepers (6-10). Between organ groups, SQ was compared via logistic regression analysis with generalized estimating equations. Within the group reporting persistently poor SQ, we used logistic regression or Kaplan-Meier analysis as appropriate to check for differences in global quality of life and survival.
Results: In a sample of 1173 transplant patients (age: 52.1-13.2 years; 65% males; 66% kidney, 17% liver, 10% lung, 7% heart) transplanted between 2008 and 2012, pre-transplant poor SQ was highest in liver (50%) and heart (49%) recipients. Overall, poor SQ decreased significantly from pre-transplant (38%) to 24 months post-transplant (26%) and remained stable at 3 years (29%). Patients reporting persistently poor SQ had significantly more depressive symptomatology and lower global quality of life.
Conclusion: Because self-reported poor SQ is related to poorer global quality of life, these results emphasize the need for further studies to find suitable treatment options for poor SQ in transplant recipients.

Background Return to work with or after a chronic disease is a dynamic process influenced by a variety of interactions between personal, work, societal and medical resources or constraints. The aim of this study was to identify predictors for employment 12 months after transplantation in kidney patients, applying a bio-psycho-social model.

Methods All kidney patients followed in the Swiss Transplant Cohort between May 2008 and December 2012, aged 18 to 65 were assessed before, 6 and 12 months after transplantation.
Results Of the 689 included patients, 56.2% worked 12 months post-transplantation compared to 58.9% pre-transplantation. Age, education, self-perceived health (6 months post-transplantation), pre-transplantation employment and receiving an organ from a living donor are significant predictors of employment post-transplantation. Moreover, while self-perceived health increased post-transplantation, depression score decreased only among those employed 12 months post-transplantation. Pre-transplantation employment status was the main predictor for post-transplantation employment (OR = 18.6) and was associated with sex, age, education, depression and duration of dialysis. An organ from a living donor (42.1%) was more frequent in younger patients, with higher education, no diabetes and shorter waiting time to surgery.
Conclusion Transplantation did not increase employment in end-stage kidney disease patients but helped maintaining employment. Pre-transplantation employment has been confirmed to be the most important predictor of post-transplantation employment. Furthermore, socio-demographic and individual factors predicted directly and indirectly the post-transplantation employment status. With living donor, an additional predictor linked to social factors and the medical procedure has been identified.

Obesity and weight gain are serious concerns after solid organ transplantation (Tx); however, no unbiased comparison regarding body weight parameter evolution across organ groups has yet been performed. Using data from the prospective nationwide Swiss Transplant Cohort Study, we compared the evolution of weight parameters up to 3 years post&dash;Tx in 1359 adult kidney (58.3%), liver (21.7%), lung (11.6%), and heart (8.4%) recipients transplanted between May 2008 and May 2012. Changes in mean weight and body mass index (BMI ) category were compared to reference values from 6 months post&dash;Tx. At 3 years post&dash;Tx, compared to other organ groups, liver Tx recipients showed the greatest weight gain (mean 4.8±10.4 kg), 57.4% gained >5% body weight, and they had the highest incidence of obesity (38.1%). After 3 years, based on their BMI categories at 6 months, normal weight and obese liver Tx patients, as well as underweight kidney, lung and heart Tx patients had the highest weight gains. Judged against international Tx patient data, the majority of our Swiss Tx recipients’ experienced lower post&dash;Tx weight gain. However, our findings show weight gain pattern differences, both within and across organ Tx groups that call for preventive measures.

Aim

To present the rationale, design and methodology of the GERAS project, which examines whether assessment of frailty and mild cognitive impairment could enhance risk prediction for biomedical, psychosocial outcomes and foster efficient resource allocation in kidney transplantation.

Background

For the burgeoning cohort of older patients considered for kidney transplantation, evidence gaps regarding frailty and mild cognitive impairment limit clinical decision&dash;making and medical management. As known risk factors for ‘hard’ clinical outcomes in chronic illness, both require further study in transplantation. Integrating these and other bio&dash;psychosocial factors into a comprehensive pre&dash;transplant patient assessment will provide insights regarding economic implications and may improve risk prediction.

Design

A nation&dash;wide multi&dash;centre prospective cohort study nested in the Swiss Transplant Cohort Study.

Methods

Our nationally representative convenience sample includes 250 adult kidney transplant recipients. Data sources include the Swiss Transplant Cohort Study and primary data collected at time of transplantation, 6 months, 1 and 2 years post&dash;transplant via established measures (the Montreal Cognitive Assessment, Psychosocial Questionnaire, Fried Frailty Instrument and a blood analysis), investigator&dash;developed instruments and datasets compiled by hospitals’ management control units, sickness funds, the Swiss Federal Statistical Office and the European Renal Association. Descriptive, competing risk survival and mixed effects analyses will be performed. Research Ethics Committee approval was obtained in January 2016.

Discussion

This pioneering project jointly examines frailty and mild cognitive impairment from bio&dash;psychosocial and health economic perspectives. Results may significantly inform risk prediction, care tailoring and resource optimization to improve health outcomes in the ageing kidney transplant cohort.

Background.

Homo sapiens mature micro–ribonucleic acid (miRNA)-200b-3p and 200c-3p are predicted to bind to 3’ untranslated region of mRNA encoding human cytomegalovirus (HCMV) immediate early protein 2 (IE2). We hypothesized that expression of these miRNAs pretransplant could predict HCMV replication after solid organ transplantation (SOT).

Methods.

A total of 272 SOT recipients were HCMV-seropositive pretransplant and were managed using preemptive therapy. Pretransplant peripheral blood mononuclear cells were stimulated with HCMV followed by collection of RNA 1 day poststimulation. The miRNAs were quantified using real-time reverse transcription–polymerase chain reaction. Human foreskin fibroblasts were transfected with 200b-3p and 200c-3p and infected with HCMV 1 hour post-transfection. Protein was collected at 3 days postinfection (dpi) and 7 dpi underwent immunoblotting for IE2.

Results.

Medians of 200b-3p and 200c-3p were significantly lower in recipients with HCMV replication (n = 144) (361.6 vs 552.6, P = .035; 3586.8 vs 12986.8 copies/μL, P = .03, respectively). Multivariate regression revealed that 200b-3p ≥100 copies/μL (odds ratio [OR]: 0.53; P = .02), was associated with less HCMV replication. Transfection with 200b-3p resulted in 2.7- and 2.5-fold decreased IE2 at 3 dpi and 7 dpi, respectively, compared to mock cells.

Conclusions.

MicroRNAs may play a biologically relevant role in controlling HCMV replication post-transplant.

Letter to the editor

Background.

Solid organ transplant (SOT) recipients are at risk of nocardiosis, a rare opportunistic bacterial infection, but prognosis and outcome of these patients are poorly defined. Our objectives were to identify factors associated with 1-year mortality after nocardiosis and describe the outcome of patients receiving short-course antibiotics (≤120 days).

Methods.

We analyzed data from a multicenter European case-control study that included 117 SOT recipients with nocardiosis diagnosed between 2000 and 2014. Factors associated with 1-year all-cause mortality were identified using multivariable conditional logistic regression.

Results.

One-year mortality was 10-fold higher in patients with nocardiosis (16.2%, 19/117) than in control transplant recipients (1.3%, 3/233, P < .001). A history of tumor (odds ratio [OR], 1.4; 95% confidence interval [CI], 1.1–1.8), invasive fungal infection (OR, 1.3; 95% CI, 1.1–1.5), and donor age (OR, 1.0046; 95% CI, 1.0007–1.0083) were independently associated with 1-year mortality. Acute rejection in the year before nocardiosis was associated with improved survival (OR, 0.85; 95% CI, 0.73–0.98). Seventeen patients received short-course antibiotics (median duration 56 [24–120] days) with a 1-year success rate (cured and surviving) of 88% and a 5.9% risk of relapse (median follow-up 49 [6–136] months).

Conclusions.

One-year mortality was 10-fold higher in SOT patients with nocardiosis than in those without. Four factors, largely reflecting general medical condition rather than severity and/or management of nocardiosis, were independently associated with 1-year mortality. Patients who received short-course antibiotic treatment had good outcomes, suggesting that this may be a strategy for further study.

In cystic fibrosis (CF) patients, chronic airway infection by Pseudomonas leads to progressive lung destruction ultimately requiring lung transplantation (LT). Following LT, CF-adapted Pseudomonas strains, potentially originating from the sinuses, may seed the allograft leading to infections and reduced allograft survival. We investigated whether CF-adapted Pseudomonas populations invade the donor microbiota and adapt to the non-CF allograft. We collected sequential Pseudomonas isolates and airway samples from a CF-lung transplant recipient during two years, and followed the dynamics of the microbiota and Pseudomonas populations. We show that Pseudomonas invaded the host microbiota within three days post-LT, in association with a reduction in richness and diversity. A dominant mucoid and hypermutator mutL lineage was replaced after 11 days by non-mucoid strains. Despite antibiotic therapy, Pseudomonas dominated the allograft microbiota until day 95. We observed positive selection of pre-LT variants and the appearance of novel mutations. Phenotypic adaptation resulted in increased biofilm formation and swimming motility capacities. Pseudomonas was replaced after 95 days by a microbiota dominated by Actinobacillus. In conclusion, mucoid Pseudomonas adapted to the CF-lung remained able to invade the allograft. Selection of both pre-existing non-mucoid subpopulations and of novel phenotypic traits suggests rapid adaptation of Pseudomonas to the non-CF allograft.

Most countries exclude human immunodeficiency virus (HIV )&dash;positive patients from organ donation because of concerns regarding donor&dash;derived HIV transmission. The Swiss Federal Act on Transplantation has allowed organ transplantation between HIV &dash;positive donors and recipients since 2007. We report the successful liver transplantation from an HIV &dash;positive donor to an HIV &dash;positive recipient. Both donor and recipient had been treated for many years with antiretroviral therapy and harbored multidrug&dash;resistant viruses. Five months after transplantation, HIV viremia remains undetectable. This observation supports the inclusion of appropriate HIV &dash;positive donors for transplants specifically allocated to HIV &dash;positive recipients.

Background

Maximal exercise capacity after heart transplantion (HTx) is reduced to the 50–70% level of healthy controls when assessed by cardiopulmonary exercise testing (CPET) despite of normal left ventricular function of the donor heart. This study investigates the role of donor heart β1 and β2- adrenergic receptor (AR) polymorphisms for maximal exercise capacity after orthotopic HTx.

Methods

CPET measured peak VO2 as outcome parameter for maximal exercise in HTx recipients ≥9 months and ≤4 years post-transplant (n = 41; mean peak VO2: 57±15% of predicted value). Donor hearts were genotyped for polymorphisms of the β1-AR (Ser49Gly, Arg389Gly) and the β2-AR (Arg16Gly, Gln27Glu). Circumferential shortening of the left ventricle was measured using magnetic resonance based CSPAMM tagging.

Results

Peak VO2 was higher in donor hearts expressing the β1-Ser49Ser alleles when compared with β1-Gly49 carriers (60±15% vs. 47±10% of the predicted value; p = 0.015), and by trend in cardiac allografts with the β1-AR Gly389Gly vs. β1-Arg389 (61±15% vs. 54±14%, p = 0.093). Peak VO2 was highest for the haplotype Ser49Ser-Gly389, and decreased progressively for Ser49Ser-Arg389Arg > 49Gly-389Gly > 49Gly-Arg389Arg (adjusted R2 = 0.56, p = 0.003). Peak VO2 was not different for the tested β2-AR polymorphisms. Independent predictors of peak VO2 (adjusted R2 = 0.55) were β1-AR Ser49Gly SNP (p = 0.005), heart rate increase (p = 0.016), and peak systolic blood pressure (p = 0.031). Left ventricular (LV) motion kinetics as measured by cardiac MRI CSPAMM tagging at rest was not different between carriers and non-carriers of the β1-AR Gly49allele.

Conclusion

Similar LV cardiac motion kinetics at rest in donor hearts carrying either β1-AR Gly49 or β1-Ser49Ser variant suggests exercise-induced desensitization and down-regulation of the β1-AR Gly49 variant as relevant pathomechanism for reduced peak VO2 in β1-AR Gly49 carriers.

Rationale: In lung transplant recipients, long-term graft survival relies on the control of inflammation and tissue remodeling to maintain graft functionality and avoid chronic lung allograft dysfunction. Although advances in clinical practice have improved transplant success, the mechanisms by which the balance between inflammation and remodeling is maintained are largely unknown.

Objectives: To assess whether host–microbe interactions in the transplanted lung determine the immunologic tone of the airways, and consequently could impact graft survival.

Methods: Microbiota DNA and host total RNA were isolated from 203 bronchoalveolar lavages obtained from 112 patients post-lung transplantation. Microbiota composition was determined using 16S ribosomal RNA analysis, and expression of a set of genes involved in prototypic macrophage functions was quantified using real-time quantitative polymerase chain reaction.

Measurements and Main Results: We show that the characteristics of the pulmonary microbiota aligned with distinct innate cell gene expression profiles. Although a nonpolarized activation was associated with bacterial communities consisting of a balance between proinflammatory (e.g., Staphylococcus and Pseudomonas) and low stimulatory (e.g., Prevotella and Streptococcus) bacteria, “inflammatory” and “remodeling” profiles were linked to bacterial dysbiosis. Mechanistic assays provided direct evidence that bacterial dysbiosis could lead to inflammatory or remodeling profiles in macrophages, whereas a balanced microbial community maintained homeostasis.

Conclusions: The crosstalk between bacterial communities and innate immune cells potentially determines the function of the transplanted lung offering novel pathways for intervention strategies.

Chronic lung allograft dysfunction (CLAD) is the major limitation of long-term survival after lung transplantation. Chronic lung allograft dysfunction manifests as bronchiolitis obliterans syndrome or the recently described restrictive allograft syndrome. Although numerous risk factors have been identified so far, the physiopathological mechanisms of CLAD remain poorly understood. We investigate here the immune mechanisms involved in the development of CLAD after lung transplantation. We explore the innate or adaptive immune reactions induced by the allograft itself or by the environment and how they lead to allograft dysfunction. Because current literature suggests bronchiolitis obliterans syndrome and restrictive allograft syndrome as 2 distinct entities, we focus on the specific factors behind one or the other syndromes. Chronic lung allograft dysfunction is a multifactorial disease that remains irreversible and unpredictable so far. We thus finally discuss the potential of systems-biology approach to predict its occurrence and to better understand its underlying mechanisms.

The prognostic factors and optimal therapy for invasive pulmonary aspergillosis (IPA ) after kidney transplantation (KT ) remain poorly studied. We included in this multinational retrospective study 112 recipients diagnosed with probable (75.0% of cases) or proven (25.0%) IPA between 2000 and 2013. The median interval from transplantation to diagnosis was 230 days. Cough, fever, and expectoration were the most common symptoms at presentation. Bilateral pulmonary involvement was observed in 63.6% of cases. Positivity rates for the galactomannan assay in serum and bronchoalveolar lavage samples were 61.3% and 57.1%, respectively. Aspergillus fumigatus was the most commonly identified species. Six&dash; and 12&dash;week survival rates were 68.8% and 60.7%, respectively, and 22.1% of survivors experienced graft loss. Occurrence of IPA within the first 6 months (hazard ratio [HR ]: 2.29; p&dash; value = 0.027) and bilateral involvement at diagnosis (HR : 3.00; p&dash; value = 0.017) were independent predictors for 6&dash;week all&dash;cause mortality, whereas the initial use of a voriconazole&dash;based regimen showed a protective effect (HR : 0.34; p&dash; value = 0.007). The administration of antifungal combination therapy had no apparent impact on outcome. In conclusion, IPA entails a dismal prognosis among KT recipients. Maintaining a low clinical suspicion threshold is key to achieve a prompt diagnosis and to initiate voriconazole therapy.

BACKGROUND: Occurring frequently after solid organ and hematopoietic stem cell transplantation, cytomegalovirus (CMV) replication remains a relevant cause of mortality and morbidity in affected patients. Despite these adverse effects, an increased alloreactivity of natural killer (NK) cells after CMV infection has been assumed, but the underlying physiopathological mechanisms have remained elusive.
METHODS: We used serial analyses of NK cells before and after CMV infection in kidney transplant recipients as an in vivo model for CMV primary infection to explore the imprint of CMV infection using every patient as their own control: We analyzed NK cell phenotype and function in 47 CMV seronegative recipients of CMV seropositive kidney grafts, who developed CMV primary infection posttransplant. Seronegative recipients of seronegative kidney grafts served as controls.
RESULTS: We observed a significant increase of NKG2C expressing NK cells after CMV infection (mean increase, 17.5%; 95% confidence interval [95% CI], 10.2-24.9, P < 0.001), whereas cluster of differentiation (CD)57 expressing cells decreased (mean decrease, 14.1%; 95% CI, 8.0-20.2; P < 0.001). Analysis of killer immunoglobulin-like receptor (KIR) expression showed an increase of cells expressing KIR2DL1 as their only inhibitory KIR in patients carrying the cognate ligand HLA-C2 (mean increase, 10.0%; 95% CI, 1.7-18.3; P = 0.018). In C2-negative individuals, KIR2DL1 expression decreased (mean decrease, 3.9%; 95% CI, 1.6-6.2; P = 0.001). As for activating KIR, there was no conclusive change pattern. Most importantly, we observed a significantly higher NK cell degranulation and IFNγ production in response to different target cells (target K562, CD107a: mean increase, 9.9%; 95% CI, 4.8-15.0; P < 0.001; IFNγ: mean increase, 6.6%; 95% CI, 1.6-11.1; P < 0.001; target MRC-5, CD107a: mean increase, 6.9%; 95% CI, 0.7-13.1; P = 0.03; IFNγ: mean increase, 4.8%; 95% CI, 1.7-7.8; P = 0.002).
CONCLUSIONS: We report evidence for an increased function of NK cells induced by CMV infection. This increased in vitro functionality was seen in NKG2C-positive and NKG2C-negative subsets, arguing for an NKG2C independent mechanism of action.

Background: Lung transplantation (LT) is a recognized treatment for end-stage pulmonary disease. Bacteria from the recipient nasopharynx seed the new lungs leading to infections and allograft damage. Understanding the characteristics and topological variations of the microbiota may be important to apprehend the pathophysiology of allograft dysfunction.

Objectives: To examine the characteristics and relationship of bacterial compositions between conducting and respiratory zones of the allograft.

Methods: We performed 16S rRNA gene sequencing on bronchial aspirates (BAs) and bronchoalveolar lavages (BALs) collected in pairs in 19 patients at several time-points post-LT.

Results: The respiratory zone was characterized independently of the time post-LT by a higher bacterial richness than the conducting zone (p = 0.041). The phyla Firmicutes and Proteobacteria dominated both sampling zones, with an inverse correlation between these two phyla (Spearman r = –0.830). Samples of the same pair, as well as pairs from the same individual clustered together (Pseudo-F = 3.8652, p < 0.01). Microbiota of BA and BAL were more closely related in samples from the same patient than each sample type across different patients, with variation in community structure being mainly inter-individual (p < 0.01). Both number of antibiotics administered (p < 0.01) and time interval post-LT (p < 0.01) contributed to the variation in global microbiota structure. Longitudinal analysis of BA–BAL pairs of two patients showed dynamic wave like fluctuations of the microbiota.

Conclusions: Our results show that post-transplant respiratory zones harbor higher bacterial richness, but overall similar bacterial profiles as compared to conductive zones. They further support an individual microbial signature following LT.

After the first year post transplantation, prognostic mortality scores in kidney transplant recipients can be useful for personalizing medical management. We developed a new prognostic score based on 5 parameters and computable at 1-year post transplantation. The outcome was the time between the first anniversary of the transplantation and the patient’s death with a functioning graft. Afterwards, we appraised the prognostic capacities of this score by estimating time-dependent Receiver Operating Characteristic (ROC) curves from two prospective and multicentric European cohorts: the DIVAT (Données Informatisées et VAlidées en Transplantation) cohort composed of patients transplanted between 2000 and 2012 in 6 French centers; and the STCS (Swiss Transplant Cohort Study) cohort composed of patients transplanted between 2008 and 2012 in 6 Swiss centers. We also compared the results with those of two existing scoring systems: one from Spain (Hernandez et al.) and one from the United States (the Recipient Risk Score, RRS, Baskin-Bey et al.). From the DIVAT validation cohort and for a prognostic time at 10 years, the new prognostic score (AUC = 0.78, 95%CI = [0.69, 0.85]) seemed to present significantly higher prognostic capacities than the scoring system proposed by Hernandez et al. (p = 0.04) and tended to perform better than the initial RRS (p = 0.10). By using the Swiss cohort, the RRS and the the new prognostic score had comparable prognostic capacities at 4 years (AUC = 0.77 and 0.76 respectively, p = 0.31). In addition to the current available scores related to the risk to return in dialysis, we recommend to further study the use of the score we propose or the RRS for a more efficient personalized follow-up of kidney transplant recipients.

Background: Nocardiosis is a rare, life-threatening opportunistic infection, affecting 0.04% to 3.5% of patients after solid organ transplant (SOT). The aim of this study was to identify risk factors for Nocardia infection after SOT and to describe the presentation of nocardiosis in these patients.

Methods: We performed a retrospective case-control study of adult patients diagnosed with nocardiosis after SOT between 2000 and 2014 in 36 European (France, Belgium, Switzerland, the Netherlands, Spain) centers. Two control subjects per case were matched by institution, transplant date, and transplanted organ. A multivariable analysis was performed using conditional logistic regression to identify risk factors for nocardiosis.

Results: One hundred and seventeen cases of nocardiosis and 234 control patients were included. Nocardiosis occurred at a median of 17.5 (range, 2-244) months after transplant. In multivariable analysis, high calcineurin inhibitor trough levels in the month before diagnosis (odds ratio [OR], 6.11; 95% confidence interval [CI], 2.58-14.51), use of tacrolimus (OR, 2.65; 95% CI, 1.17-6.00) and corticosteroid dose (OR, 1.12; 95% CI, 1.03-1.22) at the time of diagnosis, patient age (OR, 1.04; 95% CI, 1.02-1.07), and length of stay in the intensive care unit after SOT (OR, 1.04; 95% CI, 1.00-1.09) were independently associated with development of nocardiosis; low-dose cotrimoxazole prophylaxis was not found to prevent nocardiosis. Nocardia farcinica was more frequently associated with brain, skin, and subcutaneous tissue infections than were other Nocardia species. Among the 30 cases with central nervous system nocardiosis, 13 (43.3%) had no neurological symptoms.

Conclusions: We identified 5 risk factors for nocardiosis after SOT. Low-dose cotrimoxazole was not found to prevent Nocardia infection. These findings may help improve management of transplant recipients.

We assessed the impact of antiviral preventive strategies on the incidence of herpes simplex virus (HSV ) and varicella&dash;zoster virus (VZV ) infections in a nationwide cohort of transplant recipients. Risk factors for the development of HSV or VZV infection were assessed by Cox proportional hazards regression. We included 2781 patients (56% kidney, 20% liver, 10% lung, 7.3% heart, 6.7% others). Overall, 1264 (45%) patients received antiviral prophylaxis (ganciclovir or valganciclovir, n = 1145; acyclovir or valacyclovir, n = 138). Incidence of HSV and VZV infections was 28.9 and 12.1 cases, respectively, per 1000 person&dash;years. Incidence of HSV and VZV infections at 1 year after transplant was 4.6% (95% confidence interval [CI] 3.5–5.8) in patients receiving antiviral prophylaxis versus 12.3% (95% CI 10.7–14) in patients without prophylaxis; this was observed particularly for HSV infections (3% [95% CI 2.2–4] versus 9.8% [95% CI 8.4–11.4], respectively). A lower rate of HSV and VZV infections was also seen in donor or recipient cytomegalovirus&dash;positive patients receiving ganciclovir or valganciclovir prophylaxis compared with a preemptive approach. Female sex (hazard ratio [HR] 1.663, p = 0.001), HSV seropositivity (HR 5.198, p < 0.001), previous episodes of rejection (HR 1.95, p = 0.004), and use of a preemptive approach (HR 2.841, p = 0.017) were significantly associated with a higher risk of HSV infection. Although HSV and VZV infections were common after transplantation, antiviral prophylaxis significantly reduced symptomatic HSV infections.

Risk factors for invasive pulmonary aspergillosis (IPA ) after kidney transplantation have been poorly explored. We performed a multinational case–control study that included 51 kidney transplant (KT) recipients diagnosed with early (first 180 posttransplant days) IPA at 19 institutions between 2000 and 2013. Control recipients were matched (1:1 ratio) by center and date of transplantation. Overall mortality among cases was 60.8%, and 25.0% of living recipients experienced graft loss. Pretransplant diagnosis of chronic pulmonary obstructive disease (COPD ; odds ratio [OR ]: 9.96; 95% confidence interval [CI ]: 1.09–90.58; p = 0.041) and delayed graft function (OR : 3.40; 95% CI : 1.08–10.73; p = 0.037) were identified as independent risk factors for IPA among those variables already available in the immediate peritransplant period. The development of bloodstream infection (OR : 18.76; 95% CI : 1.04–339.37; p = 0.047) and acute graft rejection (OR : 40.73, 95% CI : 3.63–456.98; p = 0.003) within the 3 mo prior to the diagnosis of IPA acted as risk factors during the subsequent period. In conclusion, pretransplant COPD , impaired graft function and the occurrence of serious posttransplant infections may be useful to identify KT recipients at the highest risk of early IPA . Future studies should explore the potential benefit of antimold prophylaxis in this group.

Background

Ventricular assist devices (VAD) are valuable options for patients with heart failure awaiting cardiac transplantation. We assessed the impact of pre-transplant VAD implantation on the incidence of post-transplant infections in a nationwide cohort of heart transplant recipients.

Methods

Heart transplant recipients included in the Swiss Transplant Cohort Study between May 2008 and December 2012 were analyzed. Cumulative incidence curves were used to calculate the incidence of bacterial or Candida infections (primary endpoint) and of other infections (secondary endpoint) after transplant. Cox regression models treating death as a competing risk were used to identify risk factors for the development of infection after transplant.

Results

Overall, 119 patients were included in the study, 35 with a VAD and 84 without VAD. Cumulative incidences of post-transplant bacterial or Candida infections were 37.7 % in VAD patients and 40.4 % in non-VAD patients. In multivariate analysis, the use of cotrimoxazole prophylaxis was the only variable associated with bacterial/Candida infections after transplant (HR 0.29 [95 % CI 0.15-0.57], p < 0.001), but presence of a VAD was not (HR 0.94, [95 % CI 0.38-2.32], p = 0.89, for continuous-flow devices, and HR 0.45 [0.15 – 1.34], p = 0.15, for other devices). Risk for post-transplant viral and all fungal infections was not increased in patients with VAD. One-year survival was 82.9 % (29/35) in the VAD group and 82.1 % (69/84) in the non-VAD group. All 6 patients in the VAD group that died after transplant had a history of pre-transplant VAD infection.

Conclusion

In this nationwide cohort of heart transplant recipients, the presence of VAD at the time of transplant had no influence on the development of post-transplant infections.

Background

Polygenic obesity in Solid Organ Transplant (SOT) populations is considered a risk factor for the development of metabolic abnormalities and graft survival. Few studies to date have studied the genetics of weight gain in SOT recipients. We aimed to determine whether weighted genetic risk scores (w-GRS) integrating genetic polymorphisms from GWAS studies (SNP group#1 and SNP group#2) and from Candidate Gene studies (SNP group#3) influence BMI in SOT populations and if they predict ≥10% weight gain (WG) one year after transplantation. To do so, two samples (nA = 995, nB = 156) were obtained from naturalistic studies and three w-GRS were constructed and tested for association with BMI over time. Prediction of 10% WG at one year after transplantation was assessed with models containing genetic and clinical factors.

Results

w-GRS were associated with BMI in sample A and B combined (BMI increased by 0.14 and 0.11 units per additional risk allele in SNP group#1 and #2, respectively, p-values<0.008). w-GRS of SNP group#3 showed an effect of 0.01 kg/m2 per additional risk allele when combining sample A and B (p-value 0.04). Models with genetic factors performed better than models without in predicting 10% WG at one year after transplantation.

Conclusions

This is the first study in SOT evaluating extensively the association of w-GRS with BMI and the influence of clinical and genetic factors on 10% of WG one year after transplantation, showing the importance of integrating genetic factors in the final model. Genetics of obesity among SOT recipients remains an important issue and can contribute to treatment personalization and prediction of WG after transplantation.

Background & Aims: The interaction of killer cell immunoglobulin-like receptors with their human leucocyte antigen ligands drives the activation and inhibition of natural killer cells. Natural killer cells could be implicated in the development of liver fibrosis in chronic hepatitis C. Methods: We analysed 206 non-transplanted and 53 liver transplanted patients, selected according to their Metavir fibrosis stage. Several variables such as the number of activator killer cell immunoglobulin-like receptors or the human leucocyte antigen ligands were considered in multinomial and logistic regression models. Possible confounding variables were also investigated. Results: The killer cell immunoglobulin-like receptors were not significant predictors of the fibrosis stage. Conversely, a significant reduction of the human leucocyte antigen-C1C2 genotype was observed in the most advanced fibrosis stage group (F4) in both cohorts. Furthermore, the progression rate of fibrosis was almost 10 times faster in the subgroup of patients after liver transplantation, and human leucocyte antigen-C1C2 was significantly reduced in this cohort compared with non-transplanted patients. Conclusion: This study suggests a possible role of killer cell immunoglobulin-like receptors and their ligands in the development of liver damage. The absence of C1 and C2 ligands heterozygosity could lead to less inhibition of natural killer cells and a quicker progression to a high level of fibrosis in patients infected with hepatitis C virus, especially following liver transplantation.

Metabolic syndrome after transplantation is a major concern following solid organ transplantation (SOT). The CREB-regulated transcription co-activator 2 (CRTC2) regulates glucose metabolism. The effect of CRTC2 polymorphisms on new-onset diabetes after transplantation (NODAT) was investigated in a discovery sample of SOT recipients (n1=197). Positive results were tested for replication in two samples from the Swiss Transplant Cohort Study (STCS, n2=1294 and n3=759). Obesity and other metabolic traits were also tested. Associations with metabolic traits in population-based samples (n4=46’186, n5=123’865, n6>100,000) were finally analyzed. In the discovery sample, CRTC2 rs8450-AA genotype was associated with NODAT, fasting blood glucose and body mass index (Pcorrected<0.05). CRTC2 rs8450-AA genotype was associated with NODAT in the second STCS replication sample (odd ratio (OR)=2.01, P=0.04). In the combined STCS replication samples, the effect of rs8450-AA genotype on NODAT was observed in patients having received SOT from a deceased donor and treated with tacrolimus (n=395, OR=2.08, P=0.02) and in non-kidney transplant recipients (OR=2.09, P=0.02). Moreover, rs8450-AA genotype was associated with overweight or obesity (n=1215, OR=1.56, P=0.02), new-onset hyperlipidemia (n=1007, OR=1.76, P=0.007), and lower high-density lipoprotein-cholesterol (n=1214, β=-0.08, P=0.001). In the population-based samples, a proxy of rs8450G>A was significantly associated with several metabolic abnormalities. CRTC2 rs8450G>A appears to have an important role in the high prevalence of metabolic traits observed in patients with SOT. A weak association with metabolic traits was also observed in the population-based samples.

Background. Single-nucleotide polymorphisms (SNPs) in immune genes have been associated with susceptibility to invasive mold infection (IMI) among hematopoietic stem cell but not solid-organ transplant (SOT) recipients.

Methods. Twenty-four SNPs from systematically selected genes were genotyped among 1101 SOT recipients (715 kidney transplant recipients, 190 liver transplant recipients, 102 lung transplant recipients, 79 heart transplant recipients, and 15 recipients of other transplants) from the Swiss Transplant Cohort Study. Association between SNPs and the end point were assessed by log-rank test and Cox regression models. Cytokine production upon Aspergillus stimulation was measured by enzyme-linked immunosorbent assay in peripheral blood mononuclear cells (PBMCs) from healthy volunteers and correlated with relevant genotypes.

Results. Mold colonization (n = 45) and proven/probable IMI (n = 26) were associated with polymorphisms in the genes encoding interleukin 1β (IL1B; rs16944; recessive mode, P = .001 for colonization and P = .00005 for IMI, by the log-rank test), interleukin 1 receptor antagonist (IL1RN; rs419598; P = .01 and P = .02, respectively), and β-defensin 1 (DEFB1; rs1800972; P = .001 and P = .0002, respectively). The associations with IL1B and DEFB1 remained significant in a multivariate regression model (P = .002 for IL1B rs16944; P = .01 for DEFB1 rs1800972). The presence of 2 copies of the rare allele of rs16944 or rs419598 was associated with reduced Aspergillus-induced interleukin 1β and tumor necrosis factor α secretion by PBMCs.

Conclusions. Functional polymorphisms in IL1B and DEFB1 influence susceptibility to mold infection in SOT recipients. This observation may contribute to individual risk stratification.

BACKGROUND: Natural killer cell function is regulated by inhibitory and activating killer cell immunoglobulin-like receptors (KIR). Previous studies have documented associations of KIR genotype with the risk of cytomegalovirus (CMV) replication after solid organ transplantation.

METHODS: In this study of 649 solid organ transplant recipients, followed prospectively for infectious disease events within the Swiss Transplant Cohort Study, we were interested to see if KIR genotype associated with virus infections other than CMV.

RESULT: We found that KIR B haplotypes (which have previously been linked to protection from CMV replication) were associated with protection from varicella zoster virus infection (hazard ratio, 0.43; 95% confidence interval, 0.21-0.91; P = 0.03). No significant associations were detected regarding the risk of herpes simplex, Epstein-Barr virus or BK polyomavirus infections.

CONCLUSIONS: In conclusion, these data provide evidence that the relative protection of KIR haplotype B from viral replication after solid organ transplantation may extend beyond CMV to other herpes viruses, such as varicella zoster virus and possibly Epstein-Barr virus.

Donor PTX3 polymorphisms were shown to influence the risk of invasive aspergillosis among hematopoietic stem cell transplant recipients. Here, we show that PTX3 polymorphisms are independent risk factors for invasive mold infections among 1101 solid organ transplant recipients, thereby strengthening their role in mold infection pathogenesis and patients’ risk stratification.

Reply to the editor

Prospective cohort studies significantly contribute to answering specific research questions in a defined population. Since 2008, the Swiss Transplant Cohort Study (STCS) systematically enrolled >95 % of all transplant recipients in Switzerland, collecting predefined data at determined time points. Designed as an open cohort, the STCS has included >3900 patients to date, with a median follow-up of 2.96 years (IQR 1.44–4.73). This review highlights some relevant findings in the field of transplant-associated infections gained by the STCS so far. Three key general aspects have crystallized: (i) Well-run cohort studies are a powerful tool to conduct genetic studies, which are crucially dependent on a meticulously described phenotype. (ii) Long-term real-life observations are adding a distinct layer of information that cannot be obtained during randomized studies. (iii) The systemic collection of data, close interdisciplinary collaboration, and continuous analysis of some key outcome data such as infectious diseases endpoints can improve patient care.

Background Cytomegalovirus (CMV) replication has been associated with more risk for solid organ graft rejection. We wondered whether this association still holds when patients at risk receive prophylactic treatment for CMV.

Methods We correlated CMV infection, biopsy-proven graft rejection, and graft loss in 1,414 patients receiving heart (n=97), kidney (n=917), liver (n=237), or lung (n=163) allografts reported to the Swiss Transplant Cohort Study.
Results Recipients of all organs were at an increased risk for biopsy-proven graft rejection within 4 weeks after detection of CMV replication (hazard ratio [HR] after heart transplantation, 2.60; 95% confidence interval [CI], 1.34-4.94, P<0.001; HR after kidney transplantation, 1.58; 95% CI, 1.16-2.16, P=0.02; HR after liver transplantation, 2.21; 95% CI, 1.53-3.17, P<0.001; HR after lung transplantation, 5.83; 95% CI, 3.12-10.9, P<0.001. Relative hazards were comparable in patients with asymptomatic or symptomatic CMV infection. The CMV donor or recipient serological constellation also predicted the incidence of graft rejection after liver and lung transplantation, with significantly higher rates of rejection in transplants in which donor or recipient were CMV seropositive (non-D-/R-), compared with D- transplant or R- transplant (HR, 3.05; P=0.002 for liver and HR, 2.42; P=0.01 for lung transplants). Finally, graft loss occurred more frequently in non-D- or non-R- compared with D- transplant or R- transplant in all organs analyzed. Valganciclovir prophylactic treatment seemed to delay, but not prevent, graft loss in non-D- or non-R- transplants.
Conclusion Cytomegalovirus replication and donor or recipient seroconstellation remains associated with graft rejection and graft loss in the era of prophylactic CMV treatment.

Although medication nonadherence (MNA) is a major risk factor for poor outcomes, the evolution of MNA from pre&dash; to 3 years post&dash;transplant among the four major organ transplant groups remains unknown. Therefore, this study described this evolution and investigated whether pretransplant MNA predicts post&dash;transplant immunosuppressive medication nonadherence (IMNA). Adult participants (single transplant, pretransplant and ≤1 post&dash;transplant assessment, using medications pretransplant) in the Swiss Transplant Cohort Study (a prospective nation&dash;wide cohort study) were included. Nonadherence, defined as any deviation from dosing schedule, was assessed using two self&dash;report questions pretransplant and at 6, 12, 24 and 36 months post&dash;transplant. Nonadherence patterns were modelled using generalized estimating equations. The sample included 1505 patients (average age: 52.5 years (SD: 13.1); 36.3% females; 924 renal, 274 liver, 181 lung, 126 heart). The magnitude and variability of self&dash;reported MNA decreased significantly from pretransplant to 6 months post&dash;transplant (OR = 0.21; 95% CI: 0.16–0.27). Post&dash;transplant IMNA increased continuously from 6 months to 3 years post&dash;transplant (OR = 2.75; 95% CI: 1.97–3.85). Pretransplant MNA was associated with threefold higher odds of post&dash;transplant IMNA (OR = 3.10; 95% CI: 2.29–4.21). As pretransplant MNA predicted post&dash;transplant IMNA and a continuous increase in post&dash;transplant IMNA was observed, early adherence&dash;supporting interventions are indispensible.

Background The burden of enterococcal infections has increased over the last decades with vancomycin-resistant enterococci (VRE) being a major health problem. Solid organ transplantation is considered as a risk factor. However, little is known about the relevance of enterococci in solid organ transplantation recipients in areas with a low VRE prevalence.
Methods We examined the epidemiology of enterococcal events in patients followed in the Swiss Transplant Cohort Study between May 2008 and September 2011 and analyzed risk factors for infection, aminopenicillin resistance, treatment, and outcome.
Results Of the 1234 patients, 255 (20.7%) suffered from 392 enterococcal events (185 [47.2%] infections, 205 [52.3%] colonizations, and 2 events with missing clinical information). Only 2 isolates were VRE. The highest infection rates were found early after liver transplantation (0.24/person-year) consisting in 58.6% of Enterococcus faecium. The highest colonization rates were documented in lung transplant recipients (0.33/person-year), with 46.5% E.faecium. Age, prophylaxis with a betalactam antibiotic, and liver transplantation were significantly associated with infection. Previous antibiotic treatment, intensive care unit stay, and lung transplantation were associated with aminopenicillin resistance. Only 4/205 (2%) colonization events led to an infection. Adequate treatment did not affect microbiological clearance rates. Overall mortality was 8%; no deaths were attributable to enterococcal events.
Conclusions Enterococcal colonizations and infections are frequent in transplant recipients. Progression from colonization to infection is rare. Therefore, antibiotic treatment should be used restrictively in colonization. No increased mortality because of enterococcal infection was noted.

Background. Polymorphisms in IFNL3 and IFNL4, the genes encoding interferon λ3 and interferon λ4, respectively, have been associated with reduced hepatitis C virus clearance. We explored the role of such polymorphisms on the incidence of cytomegalovirus (CMV) infection in solid-organ transplant recipients.

Methods. White patients participating in the Swiss Transplant Cohort Study in 2008–2011 were included. A novel functional TT/-G polymorphism (rs368234815) in the CpG region upstream of IFNL3 was investigated.

Results. A total of 840 solid-organ transplant recipients at risk for CMV infection were included, among whom 373 (44%) received antiviral prophylaxis. The 12-month cumulative incidence of CMV replication and disease were 0.44 and 0.08 cases, respectively. Patient homozygous for the minor rs368234815 allele (−G/−G) tended to have a higher cumulative incidence of CMV replication (subdistribution hazard ratio [SHR], 1.30 [95% confidence interval {CI}, .97–1.74]; P = .07), compared with other patients (TT/TT or TT/−G). The association was significant among patients followed by a preemptive approach (SHR, 1.46 [95% CI, 1.01–2.12]; P = .047), especially in patients receiving an organ from a seropositive donor (SHR, 1.92 [95% CI, 1.30–2.85]; P = .001), but not among those who received antiviral prophylaxis (SHR, 1.13 [95% CI, .70–1.83]; P = .6). These associations remained significant in multivariate competing risk regression models.

Conclusions. Polymorphisms in the IFNL3/4 region influence susceptibility to CMV replication in solid-organ transplant recipients, particularly in patients not receiving antiviral prophylaxis.

Previous studies have associated activating Killer cell Immunoglobulin-like Receptor (KIR) genes with protection from cytomegalovirus (CMV) replication after organ transplantation. Whether KIR-associated protection is operating in the context of primary infection, re-activation, or both, remains unknown. Here we correlated KIR genotype and CMV serostatus at the time of transplantation with rates of CMV viremia in 517 heart (n=57), kidney (n=223), liver (n=165) or lung (n=72) allograft recipients reported to the Swiss Transplant Cohort Study. Across the entire cohort we found B haplotypes-which in contrast to A haplotypes may contain multiple activating KIR genes-to be protective in the most immunosuppressed patients (receiving anti-thynnocyte globulin induction and intensive maintenance imnnunosuppression) (hazard ratio after adjustment for covariates 0.46, 95% confidence interval 0.29-0.75, P=0.002). Notably, a significant protection was detected only in recipients who were CMV-seropositive at the time of transplantation (HR 0.45, 95% CI 0.26-0.77, P=0.004), but not in CMV seronegative recipients (HR 0.59, 95% CI 0.22-1.53,P=0.28). These data indicate a prominent role for KIR-and presumably natural killer (NK) cells-in the control of CMV replication in CMV seropositive organ transplant recipients treated with intense immunosuppression.

Background: CLAD is an irreversible and heterogeneous condition, associating Bronchiolitis Obliterans Syndrome (BOS), and Restrictive Allograft Syndrome (RAS). RAS and early onset of BOS are correlated with a poor prognosis and a significant morbidity in lung transplant recipients. As a part of SysCLAD, a FP-7 funded project aimed to predict CLAD, this study was designed to find biomarkers of CLAD in lung transplant recipients from the French cohort of lung transplant COLT and the Swiss cohort STCS, by using 2 mass spectrometry (MS) techniques.

Methods: BALF and plasma in the 200 first patients of COLT cohort who reached 3 years post-transplantation or developed an early form of CLAD were selected for analysis from systematic visits at months 6 and 12. First, SELDI-TOF MS analysis, a high-throughput method, allowed obtaining individual proteomic profiles using 3 complementary arrays: CM10 (cation array), Q10 (anion array) and IMAC-Cu (copper array). Furthermore, after pooling samples according to patients' phenotype (BOS, RAS, stable), iTRAQ-MALDI-TOF MS and MS/MS analysis, a sensitive and quantitative method, allowed biomarker identification after peptide separation by off-gel fractionation and nano-reversed phase chromatography.

Results: In a pilot study, 45 proteins were differentially expressed in BALF with SELDI-TOF MS analysis. Identification and quantification of these potential biomarkers is currently performed with iTRAQ analysis.

Conclusion: Identification and validation of early biomarkers of CLAD with these two complementary methods may help to understand involved mechanisms and to earlier diagnose CLAD onset at a reversible stage.

Background The aims of this study were to determine the prevalence of immunosuppressive non-adherence (NA) in renal transplant patients and describe whether the degree of daytime sleepiness (DS) and depressive symptomatology are associated with immunosuppressive NA.
Methods Using a cross-sectional design, 926 home-dwelling renal transplant recipients who were transplanted at one of three Swiss transplant centers provided data by self-report. The Basel Assessment of Adherence Scale for immunosuppressive was used to measure the following: taking, timing, and overall NA to immunosuppressive medication. DS was assessed with the Epworth Sleepiness Scale (ESS) (cut-off 6 for DS) and the Swiss Transplant Cohort Study DS item (cut-off 4 for DS), and depressive symptomatology was assessed with the Depression, Anxiety, and Stress Scale (cut-off>10). An ordinal logistical regression model was applied for statistical analysis.
Results The prevalence of the ESS-DS was 51%. NA for taking, timing, and the median overall NA level assessed by 0-100% visual analog scale (VAS) was 16%, 42%, and 0%, respectively. Based on the multivariate analysis, DS was significantly associated (p<0.001) with taking (1.08 [1.04-1.13]), timing (1.07 [1.03-1.10]), and overall NA (1.09 [1.05-1.13]). Very similar results were found for the Swiss Transplant Cohort Study DS item.

Conclusion DS is associated with immunosuppressive medication NA in renal transplant recipients. Admittedly, the association's strength is limited.

In Switzerland, organ procurement is well organized at the national-level but transplant outcomes have not been systematically monitored so far. Therefore, a novel project, the Swiss Transplant Cohort Study (STCS), was established. The STCS is a prospective multicentre study, designed as a dynamic cohort, which enrolls all solid organ recipients at the national level. The features of the STCS are a flexible patient-case system that allows capturing all transplant scenarios and collection of patient-specific and allograft-specific data. Beyond comprehensive clinical data, specific focus is directed at psychosocial and behavioral factors, infectious disease development, and bio-banking. Between May 2008 and end of 2011, the six Swiss transplant centers recruited 1,677 patients involving 1,721 transplantations, and a total of 1,800 organs implanted in 15 different transplantation scenarios. 10 % of all patients underwent re-transplantation and 3% had a second transplantation, either in the past or during follow-up. 34% of all kidney allografts originated from living donation. Until the end of 2011 we observed 4,385 infection episodes in our patient population. The STCS showed operative capabilities to collect high-quality data and to adequately reflect the complexity of the post-transplantation process. The STCS represents a promising novel project for comparative effectiveness research in transplantation medicine.

We assessed the impact of antiviral prophylaxis and preemptive therapy on the incidence and outcomes of cytomegalovirus (CMV) disease in a nationwide prospective cohort of solid organ transplant recipients. Risk factors associated with CMV disease and graft failure&dash;free survival were analyzed using Cox regression models. One thousand two hundred thirty&dash;nine patients transplanted from May 2008 until March 2011 were included; 466 (38%) patients received CMV prophylaxis and 522 (42%) patients were managed preemptively. Overall incidence of CMV disease was 6.05% and was linked to CMV serostatus (D+/R− vs. R+, hazard ratio [HR] 5.36 [95% CI 3.14–9.14], p < 0.001). No difference in the incidence of CMV disease was observed in patients receiving antiviral prophylaxis as compared to the preemptive approach (HR 1.16 [95% CI 0.63–2.17], p = 0.63). CMV disease was not associated with a lower graft failure&dash;free survival (HR 1.27 [95% CI 0.64–2.53], p = 0.50). Nevertheless, patients followed by the preemptive approach had an inferior graft failure&dash;free survival after a median of 1.05 years of follow&dash;up (HR 1.63 [95% CI 1.01–2.64], p = 0.044). The incidence of CMV disease in this cohort was low and not influenced by the preventive strategy used. However, patients on CMV prophylaxis were more likely to be free from graft failure.

Background Understanding outcomes after transplant requires a biopsychosocial model that includes biomedical and psychosocial factors. The latter, to date, are assessed only in a limited way as part of transplant registries or cohort studies. The Swiss Transplant Cohort Study (STCS) is a nationwide open cohort study (starting May 2008) to systematically and prospectively assess psychosocial factors. This article describes the framework underpinning STCS's psychosocial assessment.

Methods The STCS framework was adapted from the multidimensional conceptual perspective of Dew et al to describe transplant psychosocial domains and specific outcomes by adding a time perspective, a system perspective, and interaction among domains.
Results-We propose a multidimensional, multilevel biopsychosocial framework representing mutually influencing domains from before to after transplant, and exemplify each domain by factors included in STCS and their measurement. The transplant patient, centrally positioned, is described by clinical and sociodemographic characteristics (eg, socioeconomic status, educational, professional, and relationship status). The following psychosocial domains further describe the patient: (1) physical/functional (eg, perceived health status, sleep quality, daytime sleepiness), (2) psychological (eg, depression, stress), (3) behavioral (eg, medication adherence, smoking, drug use, physical activity, sun protection), (4) social (eg, work capacity/return to work), and (5) global quality of life. Factors associated with health care system level (eg, trust in transplant team) are also included in the model.
Conclusion The STCS's psychosocial framework provides a basis for studying the interplay of biomedical, sociodemographic, psychosocial, behavioral, and health care system factors in view of transplant outcomes and therefore has the potential to guide biopsychosocial transplant research. (C) 2013 NATCO, The Organization for Transplant Professionals

Context Daytime sleepiness in kidney transplant recipients has emerged as a potential predictor of impaired adherence to the immunosuppressive medication regimen. Thus there is a need to assess daytime sleepiness in clinical practice and transplant registries. Objective To evaluate the validity of a single-item measure of daytime sleepiness integrated in the Swiss Transplant Cohort Study (STCS), using the American Educational Research Association framework. Methods Using a cross-sectional design, we enrolled a convenience sample of 926 home-dwelling kidney transplant recipients (median age, 59.69 years; 25%-75% quartile [Q25-Q75], 50.27-59.69), 63% men; median time since transplant 9.42 years (Q25-Q75, 4.93-15.85). Daytime sleepiness was assessed by using a single item from the STCS and the 8 items of the validated Epworth Sleepiness Scale. Receiver operating characteristic curve analysis was used to determine the cutoff for the STCS daytime sleepiness item against the Epworth Sleepiness Scale score. Results Based on the receiver operating characteristic curve analysis, a score greater than 4 on the STCS daytime sleepiness item is recommended to detect daytime sleepiness. Content validity was high as all expert reviews were unanimous. Concurrent validity was moderate (Spearman ρ, 0.531; P < .001) and convergent validity with depression and poor sleep quality although low, was significant (ρ, 0.235; P <.001 and ρ, 0.318, P =.002, respectively). For the group difference validity: kidney transplant recipients with moderate, severe, and extremely severe depressive symptom scores had 3.4, 4.3, and 5.9 times higher odds of having daytime sleepiness, respectively, as compared with recipients without depressive symptoms. Conclusion The accumulated evidence provided evidence for the validity of the STCS daytime sleepiness item as a simple screening scale for daytime sleepiness.

( Progress in Transplantation. 2013;23:xxx-xxx)

PURPOSE OF REVIEW: The debate on the merits of observational studies as compared with randomized trials is ongoing. We will briefly touch on this subject, and demonstrate the role of cohort studies for the description of infectious disease patterns after transplantation. The potential benefits of cohort studies for the clinical management of patients outside of the expected gain in epidemiological knowledge are reviewed. The newly established Swiss Transplantation Cohort Study and in particular the part focusing on infectious diseases will serve as an illustration. RECENT FINDINGS: A neglected area of research is the indirect value of large, multicenter cohort studies. These benefits can range from a deepened collaboration to the development of common definitions and guidelines. Unfortunately, very few data exist on the role of such indirect effects on improving quality of patient management. SUMMARY: This review postulates an important role for cohort studies, which should not be viewed as inferior but complementary to established research tools, in particular randomized trials. Randomized trials remain the least bias-prone method to establish knowledge regarding the significance of diagnostic or therapeutic measures. Cohort studies have the power to reflect a real-world situation and to pinpoint areas of knowledge as well as of uncertainty. Prerequisite is a prospective design requiring a set of inclusive data coupled with the meticulous insistence on data retrieval and quality.

Context Poor sleep quality and poor daytime functioning affect many kidney transplant patients.

Objective To evaluate the validity of 2 items assessing sleep quality and daytime functioning using the Pittsburgh Sleep Quality Index as reference standard before use in a large cohort study, following the American Psychological Associations guidelines.

Design A cross-sectional study using a psychosocial questionnaire developed for a large cohort study and the Pittsburgh Sleep Quality Index.

Sample and Setting One hundred thirty-five home-dwelling kidney transplant patients aged 21 to 76 years (mean, 51.6 years; SD, 11.9 years).

Main Outcome Measures Evidence on content, internal structure, and relation to other variables.

Results The Pittsburgh Sleep Quality Index indicated a 47.4% prevalence of poor sleep quality; the sleep quality item in the psychosocial questionnaire showed a 30.7% prevalence of poor sleep quality and a 34.1% prevalence of poor daytime functioning. Content validity was good for the psychosocial questionnaires sleep quality item but poor for its daytime functioning item. As hypothesized, the psychosocial questionnaires sleep quality item was moderately correlated with its daytime functioning item (Spearman rho, ρs = 0.520, P < .001), indicating related but distinct concepts. When combined, the 2 items from the psychosocial questionnaire showed significant correlations with the total score on the Pittsburgh Sleep Quality Index ( ρs = -0.784, P < .001), depressive symptoms ( ρs = -0.680, P < .001), perceived health status ( ρs =0.619, P <.001), and subjective health status ( ρs =0.671, P <.001) in the expected directions.

Conclusion For kidney transplant patients, validity is strong for the psychosocial questionnaires sleep quality item, but the mixed findings regarding the validity of the daytime functioning item suggest that additional items are needed to measure daytime functioning. ( Progress in Transplantation. 2011;21)