Trends in underlying causes of death in allogeneic hematopoietic cell transplant recipients over the last decade.

OBJECTIVES: Improved survival after hematopoietic cell transplantation (HCT) and an increasingly comorbid transplant population may give rise to new trends in the causes of death. METHODS: This study includes all adult allogeneic HCT recipients transplanted at Rigshospitalet between January 1, 2010 and December 31, 2019. Underlying causes of death were determined using the Classification of Death Causes after Transplantation (CLASS) method. RESULTS: Among 802 HCT recipients, 289 died during the study period. The main causes of death were relapse (N = 133, 46.0%), graft-versus-host disease (GvHD) (N = 64, 22.1%) and infections (N = 35, 12.1%). Multivariable analyses showed that with increasing transplant calendar year, a decreased risk of all-cause mortality (HR 0.92, 95% CI 0.87-0.97) and death from GvHD (HR 0.87, 95% CI 0.78-0.97) was identified, but not for other specific causes. Standardized mortality ratios (SMRs) for all-cause mortality decreased from 23.8 (95% CI 19.1-28.5) to 18.4 (95% CI 15.0-21.9) for patients transplanted in 2010-2014 versus 2015-2019, while SMR for patients who died from GvHD decreased from 8.19 (95% CI 5.43-10.94) to 3.65 (95% CI 2.13-5.18). CONCLUSIONS: As risk of all-cause mortality and death from GvHD decreases, death from relapse remains the greatest obstacle in further improvement of survival after HCT.

Predicting type 2 diabetes risk before and after solid organ transplantation using polygenic scores in a Danish cohort.

Type 2 diabetes mellitus (T2DM) can be multifactorial where both genetics and environmental factors play a role. We aimed to investigate the use of polygenic risk scores (PRS) in the prediction of pre-transplant T2DM and post-transplant diabetes mellitus (PTDM) among solid organ transplant (SOT) patients. Using non-genetic risk scores alone; and the combination with PRS, separate logistic regression models were built and compared using receiver operator curves. Patients were assessed pre-transplant and in three post-transplant periods: 0-45, 46-365 and >365 days. A higher PRS was significantly associated with increased odds of pre-transplant T2DM. However, no improvement was observed for pre-transplant T2DM prediction when comparing PRS combined with non-genetic risk scores to using non-genetic risk scores alone. This was also true for predictions of PTDM in all three post-transplant periods. This study demonstrated that polygenic risk was only associated with the risk of T2DM among SOT recipients prior to transplant and not for PTDM. Combining PRS with a clinical model of non-genetic risk scores did not significantly improve the predictive ability, indicating its limited clinical utility in identifying patients at high risk for T2DM before transplantation, suggesting that non-genetic or different genetic factors may contribute to PTDM.

Implementation of a vaccination clinic for adult solid organ transplant candidates: A single-center experience.

Vaccination is an evidence-based strategy to prevent or reduce the severity of infectious diseases (ID). Here, we aimed to describe the experience of implementing a vaccination clinic specifically targeting liver, heart, lung, and combined dual organ transplantation at a single transplantation center in Denmark. In this cohort of 242 solid organ transplant (SOT) candidates, we investigated seroprotection and the proportion of recommended vaccinations documented before transplantation. Furthermore, we registered completed vaccinations after ID consultations. The median age in our cohort was 53 years (IQR, 42-60), 60% were males (n = 135), and liver transplants (n = 138; 57%) were the most frequently planned organ transplants. Before the consultation to the vaccination clinic, influenza and pneumococcal vaccines had the highest proportion of documented vaccination (58% and 37%, respectively). Serological protection was more frequently observed for measles, mumps, or rubella (MMR, approximately 90% for each), while only 30% (n = 72) of SOT candidates showed seroprotection against pneumococcal disease. All SOT candidates required at least one of the recommended vaccines, and over 90% required three or more. At least 10% of patients in our cohort needed a live attenuated vaccine for either MMR or yellow fever. The most frequently administered vaccine was the tetanus-diphtheria-acelullar pertussis (Tdap) booster (n = 217; 90%), influenza vaccination was either administered (n = 16; 7%) or recommended (n = 226; 93%), PCV13 was administered (n = 155; 64%) or recommended (n = 27; 11%), and PPSV23 was either administered (n = 18; 7.4%) or recommended (n = 140; 58%). All SOT candidates adhered completely to their vaccination schedules. Based on our findings, we recommend prioritizing vaccination before transplantation by providing ID consultations for SOT candidates.

Associations of functional human leucocyte antigen class I groups with HIV viral load in a heterogeneous cohort.

OBJECTIVE: Human leucocyte antigen (HLA) class I alleles are the main host genetic factors involved in controlling HIV-1 viral load (VL). Nevertheless, HLA diversity has proven a significant challenge in association studies. We assessed how accounting for binding affinities of HLA class I alleles to HIV-1 peptides facilitate association testing of HLA with HIV-1 VL in a heterogeneous cohort. DESIGN: Cohort from the Strategic Timing of AntiRetroviral Treatment (START) study. METHODS: We imputed HLA class I alleles from host genetic data (2546 HIV+ participants) and sampled immunopeptidomes from 2079 host-paired viral genomes (targeted amplicon sequencing). We predicted HLA class I binding affinities to HIV-1 and unspecific peptides, grouping alleles into functional clusters through consensus clustering. These functional HLA class I clusters were used to test associations with HIV VL. RESULTS: We identified four clades totaling 30 HLA alleles accounting for 11.4% variability in VL. We highlight HLA-B∗57:01 and B∗57:03 as functionally similar but yet overrepresented in distinct ethnic groups, showing when combined a protective association with HIV+ VL (log, ß -0.25; adj. P-value < 0.05). We further demonstrate only a slight power reduction when using unspecific immunopeptidomes, facilitating the use of the inferred functional HLA groups in other studies. CONCLUSION: The outlined computational approach provides a robust and efficient way to incorporate HLA function and peptide diversity, aiding clinical association studies in heterogeneous cohorts. To facilitate access to the proposed methods and results we provide an interactive application for exploring data.

Association between ten-eleven methylcytosine dioxygenase 2 genetic variation and viral load in people with HIV.

INTRODUCTION: Identifying genetic factors that influence HIV-pathogenesis is critical for understanding disease pathways. Previous studies have suggested a role for the human gene ten-eleven methylcytosine dioxygenase 2 (TET2) in modulating HIV-pathogenesis. METHODS: We assessed whether genetic variation in TET2 was associated with markers of HIV-pathogenesis using both gene level and single nucleotide polymorphism (SNP) level association in 8512 HIV-positive persons across five clinical trial cohorts. RESULTS: Variation at both the gene and SNP-level of TET2 was found to be associated with levels of HIV viral load (HIV-VL) consistently in the two cohorts that recruited antiretroviral-naïve participants. The SNPs occurred in two clusters of high linkage disequilibrium (LD), one associated with high HIV-VL and the other low HIV-VL, and were predominantly found in Black participants. CONCLUSION: Genetic variation in TET2 was associated with HIV-VL in two large antiretroviral therapy (ART)-naive clinical trial cohorts. The role of TET2 in HIV-pathogenesis warrants further investigation.

Trends in underlying causes of death in solid organ transplant recipients between 2010 and 2020: Using the CLASS method for determining specific causes of death.

Monitoring specific underlying causes of death in solid organ transplant (SOT) recipients is important in order to identify emerging trends and health challenges. This retrospective cohort study includes all SOT recipients transplanted at Rigshospitalet between January 1st, 2010 and December 31st, 2019. The underlying cause of death was determined using the newly developed Classification of Death Causes after Transplantation (CLASS) method. Cox regression analyses assessed risk factors for all-cause and cause-specific mortality. Of the 1774 SOT recipients included, 299 patients died during a total of 7511 person-years of follow-up (PYFU) with cancer (N = 57, 19%), graft rejection (N = 55, 18%) and infections (N = 52, 17%) being the most frequent causes of death. We observed a lower risk of all-cause death with increasing transplant calendar year (HR 0.91, 95% CI 0.86-0.96 per 1-year increase), alongside death from graft rejection (HR 0.84 per year, 95% CI 0.74-0.95) and death from infections (HR 0.86 per year, 95% CI 0.77-0.97). Further, there was a trend towards lower cumulative incidence of death from cardiovascular disease, graft failure and cancer in more recent years, while death from other organ specific and non-organ specific causes did not decrease. All-cause mortality among SOT recipients has decreased over the past decade, mainly due to a decrease in graft rejection- and infection-related deaths. Conversely, deaths from a broad range of other causes have remained unchanged, suggesting that cause of death among SOT recipients is increasingly diverse and warrants a multidisciplinary effort and attention in the future.

Human Immunotypes Impose Selection on Viral Genotypes Through Viral Epitope Specificity.

BACKGROUND: Understanding the genetic interplay between human hosts and infectious pathogens is crucial for how we interpret virulence factors. Here, we tested for associations between HIV and host genetics, and interactive genetic effects on viral load (VL) in HIV-positive antiretroviral treatment-naive clinical trial participants. METHODS: HIV genomes were sequenced and the encoded amino acid (AA) variants were associated with VL, human single nucleotide polymorphisms (SNPs), and imputed HLA alleles using generalized linear models with Bonferroni correction. RESULTS: Human (388 501 SNPs) and HIV (3010 variants) genetic data were available for 2122 persons. Four HIV variants were associated with VL (P < 1.66 × 10-5). Twelve HIV variants were associated with a range of 1-512 human SNPs (P < 4.28 × 10-11). We found 46 associations between HLA alleles and HIV variants (P < 1.29 × 10-7). HIV variants and immunotypes when analyzed separately were associated with lower VL, whereas the opposite was true when analyzed in concert. Epitope binding predictions supported our observations. CONCLUSIONS: Our results show the importance of immunotype specificity on viral antigenic determinants, and the identified genetic interplay emphasizes that viral and human genetics should be studied in the context of each other.Clinical Trials Registration: NCT00867048.

The association of human leukocyte antigen alleles with clinical disease progression in HIV-positive cohorts with varied treatment strategies.

OBJECTIVES: The Strategic Timing of AntiRetroviral Treatment (START) and Strategies for Management of Antiretroviral Therapy (SMART) trials demonstrated that ART can partly reverse clinically defined immune dysfunction induced by HIV replication. As control of HIV replication is influenced by the HLA region, we explored whether HLA alleles independently influence the risk of clinical events in HIV+ individuals. DESIGN: Cohort study. METHODS: In START and SMART participants, associations between imputed HLA alleles and AIDS, infection-related cancer, herpes virus-related AIDS events, chronic inflammation-related conditions, and bacterial pneumonia were assessed. Cox regression was used to estimate hazard ratios for the risk of events among allele carriers versus noncarriers. Models were adjusted for sex, age, geography, race, time-updated CD4+ T-cell counts and HIV viral load and stratified by treatment group within trials. HLA class I and II alleles were analyzed separately. The Benjamini--Hochberg procedure was used to limit the false discovery rate to less than 5% (i.e. q value <0.05). RESULTS: Among 4829 participants, there were 132 AIDS events, 136 chronic inflammation-related conditions, 167 bacterial pneumonias, 45 infection-related cancers, and 49 herpes virus-related AIDS events. Several associations with q value less than 0.05 were found: HLA-DQB1∗06:04 and HLA-DRB1∗13:02 with AIDS (adjusted HR [95% CI] 2.63 [1.5-4.6] and 2.25 [1.4-3.7], respectively), HLA-B∗15:17 and HLA-DPB1∗15:01 with bacterial pneumonia (4.93 [2.3-10.7] and 4.33 [2.0-9.3], respectively), and HLA-A∗69:01 with infection-related cancer (15.26 [3.5-66.7]). The carriage frequencies of these alleles were 10% or less. CONCLUSION: This hypothesis-generating study suggests that certain HLA alleles may influence the risk of immune dysfunction-related events irrespective of viral load and CD4+ T-cell count.

Incidence and Impact of Parvovirus B19 Infection in Seronegative Solid Organ Transplant Recipients.

Routine monitoring of parvovirus B19 (B19V) the first 6 months posttransplantation was performed in 241 seronegative solid organ transplant (SOT) recipients. Incidence rates during the first month and the second to sixth months posttransplantation were 1.2 (95% confidence interval [CI], .33-3.2) and 0.21 (95% CI, .06-.57) per 100 recipients per month, respectively. Of the 6 SOT recipients with positive B19V polymerase chain reaction, 3 (50%) were admitted to hospital and 2 (33%) were treated with intravenous immunoglobulin. Thus, routine monitoring of B19V in seronegative SOT recipients may not be necessary. Targeted screening 1 month posttransplantation and screening upon clinical suspicion could be an alternative strategy.

Measles, Mumps, Rubella, and Varicella Zoster Virus Serology and Infections in Solid Organ Transplant Recipients During the First Year Posttransplantation.

BACKGROUND: Mumps, measles, rubella, and varicella zoster (MMRV) viruses may cause severe infections in seronegative adult solid organ transplant (SOT) recipients, but can be prevented by vaccination. We aimed to determine MMRV serostatus in adult SOT recipients before and 1 year after transplantation as well as evidence of MMRV infections in a large, prospective cohort of SOT recipients. METHODS: This was a prospective study of 1182 adult SOT recipients included in the Management of Posttransplant Infections in Collaborating Hospitals (MATCH) cohort from 2011 to 2017 with a 1-year follow-up. Systematic monitoring of MMRV serology was performed prior to transplantation and 1 year posttransplantation. Polymerase chain reaction (PCR) was used to confirm viral replication in SOT recipients presenting with clinical evidence of infection. RESULTS: Among 1182 adult SOT recipients, 28 (2.4%), 77 (6.5%), 65 (5.5%), and 22 (1.9%) were seronegative for measles, mumps, rubella, and varicella zoster virus (VZV), respectively, and 165 (14%) were seronegative for at least 1 of the MMRV viruses. One year posttransplantation, 29 of 823 (3.5%) of seropositive SOT recipients had seroreverted, and 63 of 111 (57%) of seronegative SOT recipients seroconverted for at least 1 MMRV virus. No evidence of measles, mumps, or rubella infection was found, but 8 (0.7%) SOT recipients developed symptoms and had a positive VZV PCR. CONCLUSIONS: A large proportion of SOT recipients were seronegative for at least 1 of the MMRV viruses. MMRV infections in SOT recipients may disseminate and become fatal, and although only a few cases of VZV infection were detected, results from this study suggest increase attention toward vaccination of patients waiting for SOT.

Tuberculosis among Patients Undergoing Solid Organ Transplantation or Dialysis in a Low-Endemic Country, 2004-2017.

BACKGROUND: The risk of active TB among solid organ transplant (SOT) recipients and patients initiating chronic dialysis in a country with low incidence of TB is not well elucidated. METHODS: Patients aged >18 years who were transplanted with a solid organ or initiated chronic dialysis at Copenhagen University Hospital in the period 2004-2017 were followed from date of transplantation or initiation of dialysis. Data on demographics and outcomes were obtained from nationwide registries. RESULTS: We included 1,989 SOT recipients and 1,305 patients initiating chronic dialysis, who were followed for a total of 9,785 and 4,196 person-years (PY), respectively. Only a minority of patients had been screened for latent TB prior to SOT or initiation of dialysis. The incidence rates (IRs)/100,000 PY of TB among patients from medium/high TB endemic areas were 358 (95% CI 115-1,110) and 1,266 (95% CI 681-2354) for SOT and dialysis patients, respectively, whereas IRs among patients of Danish origin were 11 (95% CI 2-81) and 31 (95% CI 4-218). CONCLUSION: The incidence of TB among immunosuppressed immigrants from medium/high TB endemic countries was very high, while the risk of TB among patients from low-endemic countries was minimal.

Evaluation of an electronic, patient-focused management system aimed at preventing cytomegalovirus disease following solid organ transplantation.

BACKGROUND: Cytomegalovirus (CMV) infection is common among solid organ transplant (SOT) recipients and may cause CMV disease. To optimize the implementation of existing prevention strategies, the Management of Post-transplant Infections in Collaborating Hospitals (MATCH) program was developed. Two key performances of MATCH (diagnosing CMV infection at low viral load (VL) and before the onset of CMV disease) were assessed prior to, during and after the implementation of MATCH. METHODS: The MATCH program included a personalized surveillance plan, prophylaxis and preemptive therapy determined by the recipient's risk of CMV infection. The plan was composed through predefined algorithms and implemented through harvesting of real-time data from medical records. Risk of CMV disease was compared for recipients transplanted during and after vs prior to the implementation of MATCH. Lung and non-lung transplants were analyzed separately. RESULTS: A total of 593, 349, 520, and 360 SOT recipients were transplanted before (2007-2010), during (2011-2012), early after (2013-2015), and late after (2016-2017) implementation of MATCH with an observed reduction of diagnostic VL (P < .001) over time. Risk of CMV disease was reduced among non-lung transplant recipients transplanted during (adjusted hazard ratios [95% CI] 0.15 [0.04-0.54], P = .003), early after (aHR 0.27 [0.11-0.63], P = .003), and late after (aHR 0.17 [0.06-0.52], P = .002) compared with prior to MATCH. No significant change was observed among lung transplants. CONCLUSION: Implementation of CMV preventive strategies through MATCH was associated with a reduced risk of CMV disease among non-lung transplant recipients. Furthermore, the limitations of VL as a sole indicator for CMV disease in lung transplants were emphasized.

Association Between Single-Nucleotide Polymorphisms in HLA Alleles and Human Immunodeficiency Virus Type 1 Viral Load in Demographically Diverse, Antiretroviral Therapy-Naive Participants From the Strategic Timing of AntiRetroviral Treatment Trial.

The impact of variation in host genetics on replication of human immunodeficiency virus type 1 (HIV-1) in demographically diverse populations remains uncertain. In the current study, we performed a genome-wide screen for associations of single-nucleotide polymorphisms (SNPs) to viral load (VL) in antiretroviral therapy-naive participants (n = 2440) with varying demographics from the Strategic Timing of AntiRetroviral Treatment (START) trial. Associations were assessed using genotypic data generated by a customized SNP array, imputed HLA alleles, and multiple linear regression. Genome-wide significant associations between SNPs and VL were observed in the major histocompatibility complex class I region (MHC I), with effect sizes ranging between 0.14 and 0.39 log10 VL (copies/mL). Supporting the SNP findings, we identified several HLA alleles significantly associated with VL, extending prior observations that the (MHC I) is a major host determinant of HIV-1 control with shared genetic variants across diverse populations and underscoring the limitations of genome-wide association studies as being merely a screening tool.

Classification of death causes after transplantation (CLASS): Evaluation of methodology and initial results.

Correct classification of death causes is an important component of transplant trials.We aimed to develop and validate a system to classify causes of death in hematopoietic stem cell (HSCT) and solid organ (SOT) transplant recipients.Case record forms (CRF) of fatal cases were completed, including investigator-designated cause of death. Deaths occurring in 2010 to 2013 were used for derivation; and were validated by deaths occurring in 2013 to 2015. Underlying cause of death (referred to as recorded underlying cause) was determined through a central adjudication process involving 2 external reviewers, and subsequently compared with the Danish National Death Cause Registry.Three hundred eighty-eight recipients died 2010 to 2015 (196 [51%] SOT and 192 [49%] HSCT). The main recorded underlying causes of death among SOT and HSCT were classified as cancer (20%, 48%), graft rejection/failure/graft-versus-host-disease (35%, 28%), and infections (20%, 11%). Kappa between the investigator-designated and the recorded underlying cause of death was 0.74 (95% CI 0.69-0.80) in derivation and comparable in the validation cohort. Death causes were concordant with the Danish National Death Cause Registry in 37.2% (95% CI 31.5-42.9) and 38.4% (95% CI 28.8-48.0) in the derivation and validation cohorts, respectively.We developed and validated a method to systematically and reliably classify the underlying cause of death among transplant recipients. There was a high degree of discordance between this classification and that in the Danish National Death Cause Registry.

Inadvertent yellow fever vaccination of a patient with Crohn's disease treated with infliximab and methotrexate.

We present a case of a 56-year-old woman with Crohn's disease, treated with methotrexate and infliximab, who inadvertently received yellow fever vaccination (YFV) prior to a journey to Tanzania. She was not previously vaccinated against YF. YFV contains live-attenuated virus, and is contraindicated in patients treated with immunosuppressive drugs. Following vaccination, the patient fell ill with influenza-like illness. Elevated transaminase levels and YF viremia were detected. Despite being immunocompromised, the patient did not develop more severe adverse effects. Neutralising antibodies to YF virus were detected on day 14 following vaccination and remained protective at least 10 months after vaccination. Limited data is available on outcomes of YFV in patients receiving immunosuppressive therapy, including biologics, and we report this case as a reminder of vigilance of vaccine recommendations in this population.