Risk of Colorectal Cancer After Solid Organ Transplantation in the United States

Solid organ transplant recipients have increased colorectal cancer (CRC) risk. We assessed CRC risk among transplant recipients and identified factors contributing to this association. The US transplant registry was linked to 15 population‐based cancer registries (1987–2010). We compared CRC risk in recipients to the general population by using standardized incidence ratios (SIRs) and identified CRC risk factors by using Poisson regression. Based on 790 cases of CRC among 224 098 transplant recipients, the recipients had elevated CRC risk (SIR 1.12, 95% confidence interval [CI] 1.04 to 1.20). The increase was driven by an excess of proximal colon cancer (SIR 1.69, 95% CI 1.53 to 1.87), while distal colon cancer was not increased (SIR 0.93, 95% CI 0.80 to 1.07), and rectal cancer was reduced (SIR 0.64, 95% CI 0.54 to 0.76). In multivariate analyses, CRC was increased markedly in lung recipients with cystic fibrosis (incidence rate ratio [IRR] 12.3, 95% CI 6.94 to 21.9, vs. kidney recipients). Liver recipients with primary sclerosing cholangitis and inflammatory bowel disease also had elevated CRC risk (IRR 5.32, 95% CI 3.73 to 7.58). Maintenance therapy with cyclosporine and azathioprine was associated with proximal colon cancer (IRR 1.53, 95% CI 1.05 to 2.23). Incidence was not elevated in a subgroup of kidney recipients treated with tacrolimus and mycophenolate mofetil, pointing to the relevance of the identified risk factors. Transplant recipients have increased proximal colon cancer risk, likely related to underlying medical conditions (cystic fibrosis and primary sclerosing cholangitis) and specific immunosuppressive regimens.     

Variation in Access to Kidney Transplantation Across Renal Programs in Ontario,Canada

In the United States, kidney transplant rates vary significantly across end‐stage renal disease (ESRD) networks. We conducted a population‐based cohort study to determine whether there was variability in kidney transplant rates across renal programs in a health care system distinct from the United States. We included incident chronic dialysis patients in Ontario, Canada, from 2003 to 2013 and determined the 1‐, 5‐, and 10‐year cumulative incidence of kidney transplantation in 27 regional renal programs (similar to U.S. ESRD networks). We also assessed the cumulative incidence of kidney transplant for “healthy” dialysis patients (aged 18–50 years without diabetes, coronary disease, or malignancy). We calculated standardized transplant ratios (STRs) using a Cox proportional hazards model, adjusting for patient characteristics (maximum possible follow‐up of 11 years). Among 23 022 chronic dialysis patients, the 10‐year cumulative incidence of kidney transplantation ranged from 7.4% (95% confidence interval [CI] 4.8–10.7%) to 31.4% (95% CI 16.5–47.5%) across renal programs. Similar variability was observed in our healthy cohort. STRs ranged from 0.3 (95% CI 0.2–0.5) to 1.5 (95% CI 1.4–1.7) across renal programs. There was significant variation in kidney transplant rates across Ontario renal programs despite patients having access to the same publicly funded health care system.     

Incidence and Predictors of Cancer Following Kidney Transplantation in Childhood

Cancer risk is increased substantially in adult kidney transplant recipients, but the long‐term risk of cancer in childhood recipients is unclear. Using the Australian and New Zealand Dialysis and Transplant Registry, the authors compared overall and site‐specific incidences of cancer after transplantation in childhood recipients with population‐based data by using standardized incidence ratios (SIRs). Among 1734 childhood recipients (median age 14 years, 57% male, 85% white), 289 (16.7%) developed cancer (196 nonmelanoma skin cancers, 143 nonskin cancers) over a median follow‐up of 13.4 years. The 25‐year cumulative incidences of any cancer were 27% (95% confidence intervals 24–30%), 20% (17–23%) for nonmelanoma skin cancer, and 14% (12–17%) for nonskin cancer (including melanoma). The SIR for nonskin cancer was 8.23 (95% CI 6.92–9.73), with the highest risk for posttransplant lymphoproliferative disease (SIR 45.80, 95% CI 32.71–62.44) and cervical cancer (29.4, 95% CI 17.5–46.5). Increasing age at transplantation (adjusted hazard ratio [aHR] per year 1.10, 95% CI 1.06–1.14), white race (aHR 3.36, 95% CI 1.61–6.79), and having a functioning transplant (aHR 2.27, 95% CI 1.47–3.71) were risk factors for cancer. Cancer risk, particularly for virus‐related cancers, is increased substantially after kidney transplantation during childhood.     

Incidence and clinical predictors of primary opportunistic deep cutaneous mycoses in solid organ transplant recipients: a multicenter cohort study

Tessari G, Naldi L, Piaserico S, Boschiero L, Nacchia F, Forni A, Rugiu C, Faggian G, Dall’Olio E, Fortina AB, Alaibac M, Sassi F, Gotti E, Fiocchi R, Fagioli S, Girolomoni G. Incidence and clinical predictors of primary opportunistic deep cutaneous mycoses in solid organ transplant recipients: a multicenter cohort study.
Clin Transplant 2010: 24: 328–333. © 2009 John Wiley & Sons A/S. Abstract: Background: Primary opportunistic deep cutaneous fungal
infections may cause significant morbidity and mortality in solid organ transplant recipients (OTR), but no data exist about their incidence, timing, and clinical predictors in a long‐term follow‐up. Patients and methods: A series of 3293 consecutive OTR including 1991 kidney, 929 heart, and 373 liver transplant recipients were enrolled. Patients were regularly followed up since time at transplantation (mean 5.5 yr ±5.9 SD) and primary opportunistic fungal infections registered. Persons‐year at risk (PYs), incidence rates (IR), incidence rate ratios (IRR), and 95% confidence intervals were computed. Results: Twenty‐two cases of deep cutaneous mycoses were detected, (IR 1.2 cases per 1000 PYs) after a mean follow‐up time since transplantation of 2.5 yr ± 2.0 SD (median 1.8 yr). Six patients had subsequent systemic involvement and three patients died of systemic dissemination. A higher risk for mycoses was observed in the first two yr after transplantation, (IRR 35.9, p < 0.0001), in renal transplant recipients (IRR 5.1 p = 0.030), and in patients transplanted after the age of 50 (IRR 11.5 p = 0.020). Conclusions: Primary deep cutaneous opportunistic mycoses in OTR occur mainly in the first two yr after transplantation, in renal transplant recipients, and in older patients.     

Recipient Outcomes Following Transplantation of Allografts From Live Kidney Donors Who Subsequently Developed End‐Stage Renal Disease

Live kidney donors have an increased risk of end‐stage renal disease (ESRD) compared with nondonors; however, it is unknown whether undetected, subclinical kidney disease exists at donation that subsequently contributes to this risk. To indirectly test this hypothesis, the authors followed the donated kidneys, by comparing the outcomes of 257 recipients whose donors subsequently developed ESRD with a matched cohort whose donors remained ESRD free. The compared recipients were matched on donor (age, sex, race/ethnicity, donor–recipient relationship), transplant (HLA mismatch, peak panel‐reactive antibody, previous transplantation, year of transplantation), and recipient (age, sex, race/ethnicity, body mass index, cause of ESRD, and time on dialysis) risk factors. Median recipient follow‐up was 12.5 years (interquartile range 7.4–17.9, maximum 20 years). Recipients of allografts from donors who developed ESRD had increased death‐censored graft loss (74% versus 56% at 20 years; adjusted hazard ratio [aHR] 1.7; 95% confidence interval [CI] 1.5–2.0; p < 0.001) and mortality (61% versus 46% at 20 years; aHR 1.5; 95% CI 1.2–1.8; p < 0.001) compared with matched recipients of allografts from donors who did not develop ESRD. This association was similar among related, spousal, and unrelated nonspousal donors. These findings support a novel view of the mechanisms underlying donor ESRD: that of pre‐donation kidney disease. However, biopsy data may be required to confirm this hypothesis.     

Treatment for presumed BK polyomavirus nephropathy and risk of urinary tract cancers among kidney transplant recipients in the United States

Recent case series describe detection of BK polyomavirus (BKV) in urinary tract cancers in kidney transplant recipients, suggesting that BKV could contribute to the development of these cancers. We assessed risk for urinary tract cancers in kidney recipients with or without treatment for presumed BKV nephropathy (tBKVN) using data from the United States Transplant Cancer Match Study (2003‐2013). Among 55 697 included recipients, 2015 (3.6%) were reported with tBKVN. Relative to the general population, incidence was similarly elevated (approximately 4.5‐fold) for kidney cancer in recipients with or without tBKVN, and incidence was not increased in either group for prostate cancer. In contrast, for invasive bladder cancer, incidence was more strongly elevated in recipients with versus without tBKVN (standardized incidence ratios 4.5 vs. 1.7; N = 48 cases), corresponding to an incidence rate ratio (IRR) of 2.9 (95% confidence interval [CI] 1.0‐8.2), adjusted for sex, age, transplant year, and use of polyclonal antibody induction. As a result, recipients with tBKVN had borderline increased incidence for all urothelial cancers combined (renal pelvis, ureter, and bladder cancers: adjusted IRR 2.2, 95% CI 0.9‐5.4; N = 89 cases). Together with reports describing BKV detection in tumor tissues, these results support an association between BKV and urothelial carcinogenesis among kidney transplant recipients.     

Comparison of De Novo Cancer Incidence in Australian Liver,Heart and Lung Transplant Recipients

Population‐based evidence on the relative risk of de novo cancer in liver and cardiothoracic transplant recipients is limited. A cohort study was conducted in Australia using population‐based liver (n = 1926) and cardiothoracic (n = 2718) registries (1984–2006). Standardized incidence ratios (SIRs) were computed by cancer type, transplanted organ and recipient age. Cox regression models were used to compare cancer incidence by transplanted organ. During a median 5‐year follow‐up, the risk of any cancer in liver and cardiothoracic recipients was significantly elevated compared to the general population (n = 499; SIR = 2.62, 95%CI 2.40–2.86). An excess risk was observed for 16 cancer types, predominantly cancers with a viral etiology. The pattern of risk by cancer type was broadly similar for heart, lung and liver recipients, except for Merkel cell carcinoma (cardiothoracic only). Seventeen cancers (10 non‐Hodgkin lymphomas), were observed in 415 pediatric recipients (SIR = 23.8, 95%CI 13.8–38.0). The adjusted hazard ratio for any cancer in all recipients was higher in heart compared to liver (1.29, 95%CI 1.03–1.63) and lung compared to liver (1.65, 95%CI 1.26–2.16). Understanding the factors responsible for the higher cancer incidence in cardiothoracic compared to liver recipients has the potential to lead to targeted cancer prevention strategies in this high‐risk population.     

Survival Benefit From Kidney Transplantation Using Kidneys From Deceased Donors Aged ≥75 Years: A Time‐Dependent Analysis

Patients with end‐stage renal disease have longer survival after kidney transplantation than they would by remaining on dialysis; however, outcome with kidneys from donors aged ≥75 years and the survival of recipients of these organs compared with their dialysis counterparts with the same probability of obtaining an organ is unknown. In a longitudinal mortality study, 2040 patients on dialysis were placed on a waiting list, and 389 of them received a first transplant from a deceased donor aged ≥75 years. The adjusted risk of death and survival were calculated by non–proportional hazards analysis with being transplanted as a time‐dependent effect. Projected years of life since placement on the waiting list was almost twofold higher for transplanted patients. Nonproportional adjusted risk of death after transplantation was 0.44 (95% confidence interval [CI] 0.61–0.32; p < 0.001) in comparison with those that remained on dialysis. Stratifying by age, adjusted hazard ratios for death were 0.17 (95% CI 0.47–0.06; p = 0.001) for those aged <65 years, 0.56 (95% CI 0.92–0.34; p = 0.022) for those aged 65–69 years and 0.82 (95% CI 1.28–0.52; p = 0.389) for those aged ≥70 years. Although kidney transplantation from elderly deceased donors is associated with reduced graft survival, transplanted patients have lower mortality than those remaining on dialysis.     

Sirolimus Use and Cancer Incidence Among US Kidney Transplant Recipients

Sirolimus has anti‐carcinogenic properties and can be included in maintenance immunosuppressive therapy following kidney transplantation. We investigated sirolimus effects on cancer incidence among kidney recipients. The US transplant registry was linked with 15 population‐based cancer registries and national pharmacy claims. Recipients contributed sirolimus‐exposed time when sirolimus claims were filled, and unexposed time when other immunosuppressant claims were filled without sirolimus. Cox regression was used to estimate associations with overall and specific cancer incidence, excluding nonmelanoma skin cancers (not captured in cancer registries). We included 32 604 kidney transplants (5687 sirolimus‐exposed). Overall, cancer incidence was suggestively lower during sirolimus use (hazard ratio [HR] = 0.88, 95% confidence interval [CI] = 0.70–1.11). Prostate cancer incidence was higher during sirolimus use (HR = 1.86, 95% CI = 1.15–3.02). Incidence of other cancers was similar or lower with sirolimus use, with a 26% decrease overall (HR = 0.74, 95% CI = 0.57–0.96, excluding prostate cancer). Results were similar after adjustment for demographic and clinical characteristics. This modest association does not provide strong evidence that sirolimus prevents posttransplant cancer, but it may be advantageous among kidney recipients with high cancer risk. Increased prostate cancer diagnoses may result from sirolimus effects on screen detection.     

Risk of cancer in retransplants compared to primary kidney transplants in the United States

Recipients of kidney transplantation have elevated risk of developing cancer. There are limited data on cancer risk in recipients of kidney retransplantation. We used data from the Transplant Cancer Match Study, which links the U.S. transplant registry with 15 cancer registries. Cancer incidence in recipients of kidney retransplantation and primary kidney transplants was compared utilizing Poisson regression, adjusting for demographic and medical characteristics. We assessed 109 224 primary recipients and 6621 retransplants. Compared to primary recipients, retransplants were younger (median age 40 vs. 46 yr), had higher PRA, and more often received induction with polyclonal antibodies (43% vs. 25%). A total of 5757 cancers were observed in primary recipients and 245 in retransplants. Overall cancer risk was similar in retransplants compared with primary recipients (incidence rate ratio [IRR] 1.06, 95% CI 0.93–1.20, adjusted for age, gender, race/ethnicity, PRA, and use of polyclonal induction). However, renal cell carcinoma (RCC) occurred in excess among retransplants (adjusted IRR 2.03, 95% CI 1.45–2.77), based on 514 cases in primary recipients and 43 cases in retransplants. Overall cancer risk did not differ in retransplants compared to primary recipients. Increased risk of RCC may be explained by the presence of acquired cystic kidney disease, which is more likely to develop with additional time with kidney disease and time spent on dialysis waiting for retransplantation.     

Pediatric Organ Transplantation and Risk of Premalignant and Malignant Tumors in Sweden

Increased cancer risks are well documented in adult organ transplant recipients. However, the spectrum of malignancies and risk in the pediatric organ transplant population are less well described. We identified all solid organ transplanted patients aged <18 in Sweden between 1970–2007 (n = 536) in the National Patient Register and linked to the Cancer Register. Nationwide rates were used to calculate standardized incidence rate ratios and 95% CI estimating the association between transplant and cancer during maximum 36 years of follow‐up. Nearly 7% of pediatric solid organ transplant recipients developed a premalignant or malignant tumor during follow‐up. Transplantation was associated with an increased risk of any cancer (n = 24, SIR = 12.5, 95% CI: 8.0–18.6): non‐Hodgkin lymphoma (NHL) (n = 13, SIR = 127, 95% CI: 68–217), renal cell (n = 3, SIR = 105, 95% CI: 22–307), vulva/vagina (n = 3, SIR = 665, 95% CI: 137–1934) and nonmelanoma skin cancers (n = 2, SIR = 64.7, 95% CI: 7.8–233.8). NHL typically appeared during childhood, while other tumors were diagnosed during adulthood. Apart from short‐term attention toward the potential occurrence of NHL, our results suggest cancer surveillance into adulthood with special attention to skin, kidneys and the female genitalia.     

A Description of the Costs of Living and Standard Criteria Deceased Donor Kidney Transplantation

Kidney transplantation improves quality of life and survival and is associated with lower health care costs compared with dialysis. We described and compared the costs of living and standard criteria for deceased donor kidney transplantation. Patients included adult recipients of a first kidney‐only transplant between April 1, 1998, and March 31, 2006, as well as their donor information. All costs (outpatient care, diagnostic imaging, inpatient care, physician claims, laboratory tests and transplant medications) for 2 years after transplant for recipients and transplant‐related costs prior to transplant (donor workup and management) were included. Complete cost information was available for 357 recipients. The mean total 2‐year cost of transplantation, including donor costs, for recipients of living and deceased donors was $118 347 (95% confidence interval [CI], 110 395–126 299) and $121 121 (95% CI 114 287–127 956), respectively (p = 0.7). The mean cost for a living donor was $18 129 (95% CI 16 845–19 414) and for a deceased donor was $36 989 (95% CI 34 421–39 558). Living donor kidney transplantation has similar costs at 2 years compared with deceased donor transplantation. These results can be used by health care decision makers to inform strategies to increase donation.     

Risk of lip cancer after solid organ transplantation in the United States

Solid organ transplant recipients have an increased risk of lip cancer, but the reasons are uncertain. Using data from the Transplant Cancer Match Study, we describe the epidemiology of lip cancer among 261 500 transplant recipients in the United States. Two hundred thirty‐one lip cancers were identified, corresponding to elevated risks for both invasive and in situ lip cancers (standardized incidence ratios of 15.3 and 26.2, respectively). Invasive lip cancer incidence was associated with male sex (adjusted incidence rate ratio [aIRR] 2.01, 95% CI 1.44‐2.82), transplanted organ (0.33, 0.20‐0.57, for liver transplants and 3.07, 1.96‐4.81, for lung transplants, compared with kidney transplants), and racial/ethnic groups other than non‐Hispanic whites (0.09, 0.04‐0.2). In addition, incidence increased with age and during the first 3 years following transplant, and was higher in recipients prescribed cyclosporine/azathioprine maintenance therapy (aIRR 1.79, 95% CI 1.09‐2.93, compared with use of tacrolimus/mycophenolate mofetil) and following a diagnosis of cutaneous squamous cell carcinoma (4.21, 2.69‐0.94). The elevation in lip cancer incidence is consistent with an effect of immunosuppression. Notably, the very strong associations with white race and history of prior skin cancer point to an important role for ultraviolet radiation exposure, and cyclosporine and azathioprine may contribute as photosensitizing or DNA damaging agents.     

Risk Factors for De Novo Malignancy Following Lung Transplantation

Risk factors for non–skin cancer de novo malignancy (DNM) after lung transplantation have yet to be identified. We queried the United Network for Organ Sharing database for all adult lung transplant patients between 1989 and 2012. Standardized incidence ratios (SIRs) were computed by comparing the data to Surveillance, Epidemiology, and End Results Program data after excluding skin squamous/basal cell carcinomas. We identified 18 093 adult lung transplant patients; median follow‐up time was 1086 days (interquartile range 436–2070). DNMs occurred in 1306 patients, with incidences of 1.4%, 4.6%, and 7.9% at 1, 3, and 5 years, respectively. The overall cancer incidence was elevated compared with that of the general US population (SIR 3.26, 95% confidence interval [CI]: 2.95–3.60). The most common cancer types were lung cancer (26.2% of all malignancies, SIR 6.49, 95% CI: 5.04–8.45) and lymphoproliferative disease (20.0%, SIR 14.14, 95% CI: 9.45–22.04). Predictors of DNM following lung transplantation were age (hazard ratio [HR] 1.03, 95% CI: 1.02–1.05, p < 0.001), male gender (HR 1.20, 95% CI: 1.02–1.42, p = 0.03), disease etiology (not cystic fibrosis, idiopathic pulmonary fibrosis or interstitial lung disease, HR 0.59, 95% CI 0.37–0.97, p = 0.04) and single‐lung transplantation (HR 1.64, 95% CI: 1.34–2.01, p < 0.001). Significant interactions between donor or recipient smoking and single‐lung transplantation were noted. On multivariable survival analysis, DNMs were associated with an increased risk of mortality (HR 1.44, 95% CI: 1.10–1.88, p = 0.009).     

Genetic Variation in Caveolin‐1 Correlates With Long‐Term Pancreas Transplant Function

Pancreas transplantation is a successful treatment for a selected group of people with type 1 diabetes. Continued insulin production can decrease over time and identifying predictors of long‐term graft function is key to improving survival. The aim of this study was to screen subjects for variation in the Caveolin‐1 gene (Cav1), previously shown to correlate with long‐term kidney transplant function. We genotyped 435 pancreas transplant donors and 431 recipients who had undergone pancreas transplantation at the Oxford Transplant Centre, UK, for all known common variation in Cav1. Death‐censored cumulative events were analyzed using Kaplan–Meier and Cox regression. Unlike kidney transplantation, the rs4730751 variant in our pancreas donors or transplant recipients did not correlate with long‐term graft function (p = 0.331–0.905). Presence of rs3801995 TT genotype (p = 0.009) and rs9920 CC/CT genotype (p = 0.010) in our donors did however correlate with reduced long‐term graft survival. Multivariate Cox regression (adjusted for donor and recipient transplant factors) confirmed the association of rs3801995 (p = 0.009, HR = 1.83;[95% CI = 1.16–2.89]) and rs9920 (p = 0.037, HR = 1.63; [95% CI = 1.03–2.73]) with long‐term graft function. This is the first study to provide evidence that donor Cav1 genotype correlates with long‐term pancreas graft function. Screening Cav1 in other datasets is required to confirm these pilot results.     

De novo Cancer‐Related Death in Australian Liver and Cardiothoracic Transplant Recipients

Evidence is sparse on the relative mortality risk posed by de novo cancers in liver and cardiothoracic transplant recipients. A retrospective cohort study was conducted in Australia using population‐based liver (n = 1926) and cardiothoracic (n = 2718) registries (1984–2006). Standardized mortality ratios (SMRs) were computed by cancer type, transplanted organ, recipient age and sex. During a median 5‐year follow‐up, de novo cancer‐related mortality risk in liver and cardiothoracic recipients was significantly elevated compared to the matched general population (n = 171; SMR = 2.83; 95% confidence interval [95%CI], 2.43–3.27). Excess risk was observed regardless of transplanted organ, recipient age group or sex. Non‐Hodgkin lymphoma was the most common cancer‐related death (n = 38; SMR = 16.6; 95%CI, 11.87–22.8). The highest relative risk was for nonmelanocytic skin cancer (n = 23; SMR = 49.6, 95%CI, 31.5–74.5), predominantly in males and in recipients of heart and lung transplants. Risk of death from de novo cancer was high in pediatric recipients (n = 5; SMR = 41.3; 95%CI, 13.4–96.5), four of the five deaths were non‐Hodgkin lymphoma. De novo cancer was a leading cause of late death, particularly in heart and liver transplantation. These findings support tailored cancer prevention strategies, surveillance to promote early detection, and guidelines for managing immunosuppression once cancer occurs.     

Factors Associated With Major Adverse Cardiovascular Events After Liver Transplantation Among a National Sample

Assessment of major adverse cardiovascular events (MACE) after liver transplantation (LT) has been limited by the lack of a multicenter study with detailed clinical information. An integrated database linking information from the University HealthSystem Consortium and the Organ Procurement and Transplant Network was analyzed using multivariate Poisson regression to assess factors associated with 30‐ and 90‐day MACE after LT (February 2002 to December 2012). MACE was defined as myocardial infarction (MI), heart failure (HF), atrial fibrillation (AF), cardiac arrest, pulmonary embolism, and/or stroke. Of 32 810 recipients, MACE hospitalizations occurred in 8% and 11% of patients at 30 and 90 days, respectively. Recipients with MACE were older and more likely to have a history of nonalcoholic steatohepatitis (NASH), alcoholic cirrhosis, MI, HF, stroke, AF and pulmonary and chronic renal disease than those without MACE. In multivariable analysis, age >65 years (incidence rate ratio [IRR] 2.8, 95% confidence interval [95% CI] 1.8–4.4), alcoholic cirrhosis (IRR 1.6, 95% CI 1.2–2.2), NASH (IRR 1.6, 95% CI 1.1–2.4), pre‐LT creatinine (IRR 1.1, 95% CI 1.04–1.2), baseline AF (IRR 6.9, 95% CI 5.0–9.6) and stroke (IRR 6.3, 95% CI 1.6–25.4) were independently associated with MACE. MACE was associated with lower 1‐year survival after LT (79% vs. 88%, p < 0.0001). In a national database, MACE occurred in 11% of LT recipients and had a negative impact on survival. Pre‐LT AF and stroke substantially increase the risk of MACE, highlighting potentially high‐risk LT candidates.     

Epidemiology of laboratory-confirmed influenza among kidney transplant recipients compared to the general population—A nationwide cohort study

Seasonal influenza causes morbidity and mortality after organ transplantation. We quantified the detection of laboratory-confirmed influenza among kidney transplant recipients compared to the general population in a nationwide cohort. All laboratory-confirmed cases of influenza and hospitalizations due to influenza among all kidney transplant recipients in our country between 1995 and 2017 were captured with database linkage from statutory national registries. Data from the general population of Finland, population 5.5 million, were used for comparisons. Annual incidences of influenza and hospitalizations due to influenza, and standardized incidence ratios (SIR) were calculated. Altogether 3904 kidney transplant recipients with a total follow-up of 37 175 patient-years were included. Incidence of laboratory-confirmed influenza was 9.0 per 1000 patient years in 2003–2019, and 18.0 per 1000 patient years during 2015–2019. The risk of laboratory-confirmed influenza was significantly higher among kidney transplant recipients compared to the general population (SIR 5.1, 95% CI 4.5–5.7). SIR for hospitalization due to influenza was 4.4 (95% CI 3.4–4.7). Mortality of the hospitalized patients was 9%, and 5% of the patients with laboratory-confirmed influenza. Detection of laboratory-confirmed influenza is increased fivefold and risk of hospitalization due to influenza more than fourfold among kidney transplant recipients compared to the general population.     

Pre‐transplant dialysis modality does not influence short‐ or long‐term outcome in kidney transplant recipients: analysis of paired kidneys from the same deceased donor

Previous studies have reported contradictory results regarding the effect of pre‐transplant dialysis modality on the outcomes after kidney transplantation (KT). To minimize the confounding effect of donor‐related variables, we performed a donor‐matched retrospective comparison of 160 patients that received only one modality of pre‐transplant dialysis (peritoneal dialysis [PD] and hemodialysis [HD] in 80 patients each) and that subsequently underwent KT at our center between January 1990 and December 2007. Cox regression models were used to evaluate the association between pre‐transplant dialysis modality and primary study outcomes (death‐censored graft survival and patient survival). To control for imbalances in recipient‐related baseline characteristics, we performed additional adjustments for the propensity score (PS) for receiving pre‐transplant PD (versus HD). There were no significant differences according to pre‐transplant dialysis modality in death‐censored graft survival (PS‐adjusted hazard ratio [aHR]: 0.65; 95% confidence interval [95% CI]: 0.25–1.68) or patient survival (aHR: 0.58; 95% CI: 0.13–2.68). There were no differences in 10‐year graft function or in the incidence of post‐transplant complications either, except for a higher risk of lymphocele in patients undergoing PD (odds ratio: 4.31; 95% CI: 1.15–16.21). In conclusion, pre‐transplant dialysis modality in KT recipients does not impact short‐ or long‐term graft outcomes or patient survival.     

Incidence,characteristics, and treatment outcomes of mycobacterial diseases in transplant recipients

The incidence, clinical characteristics, and treatment outcomes of tuberculosis (TB) and nontuberculous mycobacterial (NTM) disease developed after transplantation (TPL) in transplant recipients were investigated retrospectively. Between 1996 and 2013, 7342 solid‐organ transplantation and 1266 hematopoietic stem cell transplantation were performed at a tertiary referral center in South Korea. Among them, TB and NTM disease developed in 130 and 22 patients, respectively. The overall incidence of TB was 257.4 cases/100 000 patient‐years (95% confidence interval [CI], 215.1–305.7) and that of NTM disease was 42.7 cases/100 000 patient‐years (95% CI, 26.8–64.7). The median interval from organ TPL to the development of mycobacterial disease was 8.5 months (95% CI, 6.3–11.4) in recipients with TB patients and 24.2 months (95% CI, 13.5–55.7) in those with NTM, respectively. Among NTM patients, Mycobacterium avium–intracellulare complex was the most common causative organism, and nodular bronchiectatic type (77.8%) was the most frequent radiologic feature. Favorable treatment outcome was achieved in 83.7% (95% CI, 76.4–89.1) and 68.8% (95% CI, 44.4–85.8) of TB and NTM patients, respectively (P = 0.166). In conclusion, the overall incidence of TB was higher than that of NTM disease in transplant recipients and treatment outcomes were favorable in both drug‐susceptible TB and NTM patients.