Germinal center responses to SARS-CoV-2 mRNA vaccines in healthy and immunocompromised individuals.

Vaccine-mediated immunity often relies on the generation of protective antibodies and memory B cells, which commonly stem from germinal center (GC) reactions. An in-depth comparison of the GC responses elicited by SARS-CoV-2 mRNA vaccines in healthy and immunocompromised individuals has not yet been performed due to the challenge of directly probing human lymph nodes. Herein, through a fine-needle aspiration-based approach, we profiled the immune responses to SARS-CoV-2 mRNA vaccines in lymph nodes of healthy individuals and kidney transplant recipients (KTXs). We found that, unlike healthy subjects, KTXs presented deeply blunted SARS-CoV-2-specific GC B cell responses coupled with severely hindered T follicular helper cell, SARS-CoV-2 receptor binding domain-specific memory B cell, and neutralizing antibody responses. KTXs also displayed reduced SARS-CoV-2-specific CD4 and CD8 T cell frequencies. Broadly, these data indicate impaired GC-derived immunity in immunocompromised individuals and suggest a GC origin for certain humoral and memory B cell responses following mRNA vaccination.

COVID-19 and Kidney Disease.

COVID-19 can cause acute kidney injury and may cause or exacerbate chronic kidney diseases, including glomerular diseases. SARS-CoV-2 infection of kidney cells has been reported, but it remains unclear if viral infection of kidney cells causes disease. The most important causes of kidney injury in patients with COVID-19 include impaired renal perfusion and immune dysregulation. Chronic kidney disease, especially kidney failure with kidney replacement therapy and kidney transplant, is associated with markedly increased COVID-19 mortality. Persons with severe kidney disease have been excluded from most clinical trials of COVID-19 therapies, so therapeutic approaches must be extrapolated from studies of patients without kidney disease. Some medications used to treat COVID-19 should be avoided or used at reduced dosages in patients with severe kidney disease and in kidney transplant recipients. Additional research is needed to determine the optimal strategies to prevent and treat COVID-19 in patients with kidney disease.

Kidney replacement therapy: trends in incidence, treatment, and outcomes of myocardial infarction and stroke in a nationwide Scottish study.

BACKGROUND AND AIMS: Patients with kidney failure have a higher risk of cardiovascular disease compared with the general population. Whilst temporal trends of myocardial infarction and stroke are declining in the general population, these have not been evaluated in patients with kidney failure. This study aimed to describe national trends in the incidence, treatment, and outcomes of myocardial infarction and stroke in patients with kidney failure (i.e. on dialysis or with a kidney transplant) over a 20-year period, stratified by age and sex. METHODS: In this retrospective national data linkage study, all patients with kidney failure in Scotland (UK) receiving kidney replacement therapy between January 1996 and December 2016 were linked to national hospitalization, prescribing, and death records. The primary outcomes were the incidence of myocardial infarction and stroke, and subsequent cardiovascular death. Generalized additive models were constructed to estimate age-standardized, sex-stratified incidence rates and trends in cardiovascular and all-cause death. RESULTS: Amongst 16 050 patients with kidney failure [52 (SD 15) years; 41.5% women], there were 1992 [66 (SD 12) years; 34.8% women] and 996 [65 (SD 13) years; 45.1% women] incident myocardial infarctions and strokes, respectively, between January 1996 and December 2016. During this period, the age-standardized incidence of myocardial infarction per 100 000 decreased in men {from 4376 [95% confidence interval (CI) 3998-4785] to 1835 (95% CI 1692-1988)} and women [from 3268 (95% CI 2982-3593) to 1369 (95% CI 1257-1491)]. Similarly, the age-standardized incidence of stroke per 100 000 also decreased in men [from 1978 (95% CI 1795-2175) to 799 (95% CI 729-875)] and women [from 2234 (95% CI 2031-2468) to 903 (95% CI 824-990)]. Compared with the general population, the incidence of myocardial infarction was four- to eight-fold higher in patients with kidney failure, whilst for stroke it was two- to four-fold higher. The use of evidence-based cardioprotective treatment increased over the study period, and the predicted probability of cardiovascular death within 1 year of myocardial infarction for a 66-year-old patient with kidney failure (mean age of the cohort) fell in men (76.6% to 38.6%) and women (76.8% to 38.8%), and also decreased in both sexes following stroke (men, from 63.5% to 41.4%; women, from 67.6% to 45.8%). CONCLUSIONS: The incidence of myocardial infarction and stroke has halved in patients with kidney failure over the past 20 years but remains significantly higher than in the general population. Despite improvements in treatment and outcomes, the prognosis of these patients following myocardial infarction and stroke remains poor.

Cytomegalovirus antiviral resistance among participants in the phase 3 trial of letermovir vs valganciclovir prophylaxis in kidney transplant recipients.

BACKGROUND: In a phase 3 trial, letermovir was non-inferior to valganciclovir for CMV disease prophylaxis in CMV-seronegative (R-) kidney transplant recipients (KTRs) who received a kidney from a CMV-seropositive donor (D+). Genotypic antiviral resistance and CMV glycoprotein B (gB) genotype are reported. METHODS: Plasma samples with detectable CMV DNA were sequenced for presence of known letermovir and valganciclovir resistance-associated amino acid substitutions (RASs) encoded by CMV gene regions (UL51, UL56, UL89, UL54, UL97) and prevalence of gB (UL55) genotypes (gB1-gB5). RESULTS: 84 of 292 participants in the letermovir and 93 of 297 in the valganciclovir group had evaluable data for ≥1 gene target. Letermovir RASs were not detected in participants who received letermovir prophylaxis; however, 3 had valganciclovir RASs (pUL97). Twelve participants in the valganciclovir group had valganciclovir RASs (pUL54, pUL97); and 1 who did not receive letermovir during the trial also had letermovir RASs (pUL56). All but 1 participant responded to valganciclovir treatment irrespective of breakthrough CMV DNAemia or frequency of RASs. gB1 was the most frequent genotype across all participants and subgroups. CONCLUSION: Letermovir RASs were not detected in the letermovir group, supporting a low risk for development of resistance with letermovir prophylaxis in CMV D+R- KTRs. CLINICAL TRIALS REGISTRATION: ClinicalTrials.gov: NCT03443869, EudraCT: 2017-001055-30.

Mortality risk for kidney transplant candidates with diabetes: a population cohort study.

AIMS/HYPOTHESIS: It is unclear whether kidney transplant candidates with diabetes have equitable transplantation opportunities or have divergent survival probabilities stratified by kidney replacement therapy. The aim of this study was to investigate these two issues using national transplant registry data in the UK. METHODS: A cohort study was undertaken of prospectively collected registry data of all wait-listed people with kidney failure receiving dialysis in the UK. All people listed for their first kidney-alone transplant between 2000 and 2019 were included. Stratification was done for cause of kidney failure. Primary outcome was all-cause mortality. Time-to-death from listing was analysed using adjusted non-proportional hazard Cox regression models, with transplantation handled as a time-dependent covariate. RESULTS: A total of 47,917 wait-listed people with kidney failure formed the total study cohort, of whom 6594 (13.8%) had diabetes classified as cause of kidney failure. People with kidney failure with diabetes comprised 27.6% of the cohort (n=3681/13,359) that did not proceed to transplantation vs only 8.4% (n=2913/34,558) of the cohort that received a transplant (p<0.001). Kidney transplant candidates with diabetes were more likely to be older, of male sex and of ethnic minority background compared with those without diabetes. In an adjusted analysis, compared with remaining on dialysis, any kidney transplant provided survival benefit for wait-listed kidney transplant candidates regardless of diabetes as cause of kidney failure (RR 0.26 [95% CI 0.25, 0.27], p<0.001). CONCLUSIONS/INTERPRETATION: Kidney transplant candidates with diabetes have a lower chance of transplantation despite better survival after kidney transplantation vs remaining on dialysis. The reasons for this require further investigation to ensure equal transplantation opportunities.

Rickettsia parkeri Rickettsiosis in Kidney Transplant Recipient, North Carolina, USA, 2023.

Spotted fever rickettsiosis is rarely observed in solid organ transplant recipients, and all previously reported cases have been associated with tick bite months to years after transplantation. We describe a kidney transplant recipient in North Carolina, USA, who had a moderately severe Rickettsia parkeri infection develop during the immediate posttransplant period.

Cancer mortality after kidney transplantation: A multicenter cohort study in Italy.

Kidney transplant (KT) recipients are known to be at risk of developing several cancer types; however, cancer mortality in this population is underinvestigated. Our study aimed to assess the risk of cancer death among Italian KT recipients compared to the corresponding general population. A cohort study was conducted among 7373 individuals who underwent KT between 2003 and 2020 in 17 Italian centers. Date and cause of death were retrieved until 31 December 2020. Indirect standardization was used to estimate standardized mortality ratios (SMRs) and corresponding 95% confidence intervals (CIs). Cancer was the most common cause of death among the 7373 KT recipients, constituting 32.4% of all deaths. A 1.8-fold excess mortality (95% CI: 1.59-2.09) was observed for all cancers combined. Lymphomas (SMR = 6.17, 95% CI: 3.81-9.25), kidney cancer (SMR = 5.44, 95% CI: 2.97-8.88) and skin melanoma (SMR = 3.19, 95% CI: 1.03-6.98) showed the highest excess death risks. In addition, SMRs were increased about 1.6 to 3.0 times for cancers of lung, breast, bladder and other hematopoietic and lymphoid tissues. As compared to the general population, relative cancer mortality risk remained significantly elevated in all age groups though it decreased with increasing age. A linear temporal increase in SMR over time was documented for all cancers combined (P < .01). Our study documented significantly higher risks of cancer death in KT recipients than in the corresponding general population. Such results support further investigation into the prevention and early detection of cancer in KT recipients.

An observational cohort study examined the change point of kidney function stabilization in the initial period after transplantation.

Baseline kidney function following kidney transplantation is often used in research and clinical decision-making yet is not well defined. Here, a method to determine baseline function was proposed and validated on three single-center retrospective cohorts consisting of 922 patients from Belgium (main cohort) and two validation cohorts of 987 patients from the Netherlands and 519 patients from Germany. For each transplant, a segmented regression model was fitted on the estimated glomerular filtration rate (eGFR) evolution during the first-year post-transplantation. This yielded estimates for change point timing, rate of eGFR change before and after change point and eGFR value at change point, now considered the "baseline function". Associations of eGFR evolution with recipient/donor characteristics and the graft failure rate were assessed with linear regression and Cox regression respectively. The change point occurred on average at an eGFR value of 43.7±14.6 mL/min/1.73m2, at a median time of 6.5 days post-transplantation. Despite significant associations with several baseline donor-recipient characteristics (particularly, donor type; living vs deceased), the predictive value of these characteristics for eGFR value and timing of the change point was limited. This followed from a large heterogeneity within eGFR trajectories, which in turn indicated that favorable levels of kidney function could be reached despite a suboptimal initial evolution. Segmented regression consistently provided a good fit to early eGFR evolution, and its estimate of the change point can be a useful reference value in future analyses. Thus, our study shows that baseline kidney function after transplantation is heterogeneous and partly related to pretransplant donor characteristics.

Obesity is associated with a higher incidence of rejection in patients on belatacept: A pooled analysis from the BENEFIT/BENEFIT-EXT clinical trials.

Though belatacept is administered with a weight-based dosing schema, there has been higher clearance reported in obese patients. Therefore, we evaluated the association between body mass index (BMI) and transplant outcomes in kidney transplant recipients who were randomized to cyclosporine- or belatacept-based immunosuppression in the BENEFIT and BENEFIT-EXT randomized clinical trials. A total of 666 and 543 patients underwent randomization and transplantation in BENEFIT and BENEFIT-EXT, respectively, of which 1056 had complete data and were included in this analysis. Patients were grouped categorically according to BMI: <25, 25 to <30, and ≥30 kg/m2. BMI did influence both the incidence and severity of acute rejection. Obese patients with BMI >30 kg/m2 in the low intensity belatacept group experienced significantly more rejection at 12 months than did patients with BMI <25 kg/m2 or BMI 25 to <30 kg/m2. In both the moderate intensity belatacept and low intensity belatacept groups, obese patients with BMI >30 kg/m2 experienced significantly more severe acute rejection than did patients with BMI < 25 kg/m2 or BMI 25 to <30 kg/m2. These results suggest that obese kidney transplant recipients are at an increased risk for acute rejection when under belatacept-based immunosuppression when compared to nonobese patients.

Subsequent kidney transplant after pediatric heart transplant: Prevalence and risk factors.

Pediatric heart failure and transplantation carry associated risks for kidney failure and potential need for kidney transplant following pediatric heart transplantation (KT/pHT). This retrospective, United Network of Organ Sharing study of 10,030 pediatric heart transplants (pHTs) from 1987 to 2020 aimed to determine the incidence of waitlisting for and completion of KT/pHT, risk factors for KT/pHT, and risk factors for nonreceipt of a KT/pHT. Among pHT recipients, 3.4% were waitlisted for KT/pHT (median time of 14 years after pHT). Among those waitlisted, 70% received a KT/pHT, and 18% died on the waitlist at a median time of 0.8 years from KT/pHT waitlisting (median age of 20 years). Moderate-high sensitization at KT/pHT waitlisting (calculated panel reactive antibody, ≥ 20%) was associated with a lower likelihood of KT/pHT (adjusted hazard ratio, 0.67; 95% confidence interval, 0.47-0.95). Waitlisting for heart transplantation simultaneously with kidney transplant (adjusted hazard ratio, 3.73; 95% confidence interval, 2.01-6.92) was associated with increased risk of death on the KT/pHT waitlist. While the prevalence of KT/pHT is low, there is substantial mortality among those waitlisted for KT/pHT. These findings suggest a need to consider novel risk factors for nonreceipt of KT/pHT and death on the waitlist in prioritizing criteria/guidelines for simultaneous heart-kidney transplantation.

Rescue with obinutuzumab and daratumumab as combined B cell/plasma cell targeting approach in severe posttransplant focal segmental glomerulosclerosis recurrence.

The recurrence of primary focal segmental glomerulosclerosis (FSGS) after kidney transplantation is associated with a high graft loss rate with standard treatments based on plasmapheresis with/without rituximab. We present 2 consecutive cases of nongenetic early severe recurrent FSGS refractory to rituximab and anti-interleukin 1 treatment and with a partial response to plasmapheresis. Case 1 was a 22-year-old man who was rescue-treated for recurrence 36 weeks after transplantation with obinutuzumab (1000 mg/1.73 m2, 1 dose) and daratumumab (18 mg/kg each dose, 8 doses), resulting in plasmapheresis discontinuation and a drop of proteinuria from 29 to 2.3 g/d. Proteinuria increased with circulating CD38+ plasma cells and responded to an additional daratumumab dose. Currently, the proteinuria is 1.8 g/d, 14.5 months after discontinuing plasmapheresis and starting obinutuzumab and daratumumab therapy. Case 2 was a 15-year-old girl who was plasmapheresis dependent with 2 g/d proteinuria 82 weeks after transplantation, with a Tesio catheter in the right jugular vein as the only possible vascular access. After treatment with obinutuzumab and daratumumab (1 dose each), she achieved stable complete remission (0.3 g/d proteinuria) with persistent plasmapheresis discontinuation. These cases suggest the potential of combining obinutuzumab with daratumumab for the treatment of recurrent FSGS.

Risk for graft loss in pediatric and young adult kidney transplant recipients due to recurrent IgA nephropathy.

IgA nephropathy (IgAN) is associated with a risk for posttransplant recurrence. Data are limited regarding graft loss attributable to recurrence of IgAN among pediatric and young adult kidney transplant (KT) recipients. This was a retrospective cohort study of patients aged 0 to 25 years from the Scientific Registry of Transplant Recipients who received a primary KT for IgAN. Patients with history of KT attributable to renal dysplasia were comparators. Outcomes included the incidence of graft loss attributable to IgAN recurrence, association with donor type, and posttransplant corticosteroid use. In total, 5475 transplant recipients were included, with 1915 patients with IgAN and 3560 patients with renal dysplasia. In a multivariable Cox proportional hazards model, IgAN was associated with higher risk of graft loss (adjusted hazard ratio [aHR], 1.35; 95% CI, 1.21-1.50; P < .001) compared with dysplasia. Graft loss was attributed to recurrent disease in 5.4% of patients with IgAN. In a multivariable competing risks analysis, patients with IgAN receiving a parental living-donor kidney were more likely to report graft loss from recurrent disease compared with patients with a nonparental living donor (aHR, 0.52; 95% CI, 0.31-0.91; P = .02). Posttransplant prednisone use was not associated with improved graft survival (P = .2). These data challenge existing paradigms in posttransplant management of patients with IgAN.

Incidence and clearance of cervical and anal high-risk human papillomavirus in kidney transplant recipients: Results from a Danish prospective clinical study.

This study investigates the incidence and clearance of cervical and anal high-risk human papillomavirus (hrHPV) infection in kidney transplant recipients (KTRs) compared to immunocompetent controls. During 2016-2017, we enrolled 125 female KTRs and 125 female controls. Liquid-based cervical and anal cytology samples collected at enrollment and follow-up were tested for human papillomavirus (HPV) DNA using the CLART HPV2 test. All participants answered a questionnaire on lifestyle and sexual behavior at both examinations. KTRs had an increased age-adjusted risk of incident cervical hrHPV infection compared to controls (hazard ratio [HR] = 3.6, 95% CI = 1.2-11.2). Probability of cervical hrHPV clearance at 18 months was lower among KTRs (8.3%) than controls (66.7%). There was no statistically significant difference in anal hrHPV incidence between KTRs and controls (HR = 0.9, 95% CI = 0.4-2.0). Clearance of anal hrHPV was similar between KTRs and controls at 18 months. During the total follow-up, a lower anal hrHPV clearance, although not statistically significant, was observed among KTRs (HR = 0.3, 95% CI = 0.06-1.2). KTRs had higher incidence of cervical hrHPV and lower probability of clearance, especially of cervical hrHPV infections, than controls. Our findings support that KTRs are at increased risk of HPV infection and point to the need for targeted HPV prevention strategies, such as cervical cancer screening.

Efficacy of combined rituximab and daratumumab treatment in posttransplant recurrent focal segmental glomerulosclerosis.

Focal segmental glomerulosclerosis (FSGS) is one of the leading causes of kidney failure and it is characterized by a high rate of recurrence after kidney transplant. Moreover, FSGS recurrence is worsened by an increased risk of graft failure. Common therapies for FSGS recurrence mostly consist of plasma exchange treatments, also for prolonged time, and rituximab, with variable efficacy. We report 5 cases of early FSGS recurrence after kidney transplant, resistant to plasma exchange and rituximab treatment that subsequently resolved after combined therapy with rituximab and daratumumab. All cases were negative for genetic FSGS. The combined treatment induced a complete response in all the cases and was well tolerated. We also performed a comprehensive flow cytometry analysis in 2 subjects that may suggest a mechanistic link between plasma cells and disease activity. In conclusion, given the lack of viable treatments for recurrent FSGS, our reports support the rationale for a pilot trial testing the safety/efficacy profile of combined rituximab and daratumumab in posttransplant FSGS recurrence.

Incomplete reporting of clinically significant acute rejection episodes in the national kidney transplant registry.

Administrative claims data could provide a unique opportunity to identify acute rejection (AR) events using specific antirejection medications and to validate rejected data reported to the Organ Procurement and Transplantation Network. This retrospective cohort study examined differences in registry-reported events and those identified using claims data among adult kidney transplant recipients from 2012 to 2017 using Standard Analysis Files from the US Renal Data System. Rejection rates, survival estimates, and center-level differences were assessed using each approach. Among 45 880 first-time kidney transplant recipients, we identified 3841 AR events within 12 months of transplant reported by centers in the registry; claims data yielded 2945 events. Of all events occurring within 12 months of transplant, 48.5% were reported using registry only, 32.9% were identified using claims only, and 18.6% were identified using both approaches. A 3-year death-censored graft survival probability was 90.0%, 88.4%, and 81.2% (P < .001) for ARs identified using registry only, claims data only, and both approaches, respectively. The large discordance between registry-reported and claims-based events suggests incomplete and potentially inaccurate reporting of events in the Organ Procurement Transplant Network registry. These findings have important implications for analyses that use AR data and underscore the need for improved capture of clinically meaningful events.

Prospective observational study to validate a next-generation sequencing blood RNA signature to predict early kidney transplant rejection.

The objective of this study was to validate the performance of Tutivia, a peripheral blood gene expression signature, in predicting early acute rejection (AR) post-kidney transplant. Recipients of living or deceased donor kidney transplants were enrolled in a nonrandomized, prospective, global, and observational study (NCT04727788). The main outcome was validation of the area under the curve (AUC) of Tutivia vs serum creatinine at biopsy alone, or Tutivia + serum creatinine at biopsy. Of the 151 kidney transplant recipients, the mean cohort age was 53 years old, and 64% were male. There were 71% (107/151) surveillance/protocol biopsies and 29% (44/151) for-cause biopsies, with a 31% (47/151) overall rejection rate. Tutivia (AUC 0.69 [95% CI: 0.59-0.77]) and AUC of Tutivia + creatinine at biopsy (0.68 [95% CI: 0.59-0.77]) were greater than the AUC of creatinine at biopsy alone (0.51.4 [95% CI: 0.43-0.60]). Applying a model cut-off of 50 (scale 0-100) generated a high- and low-risk category for AR with a negative predictive value of 0.79 (95% CI: 0.71-0.86), a positive predictive value of 0.60 (95% CI: 0.45-0.74), and an odds ratio of 5.74 (95% CI: 2.63-12.54). Tutivia represents a validated noninvasive approach for clinicians to accurately predict early AR, beyond the current standard of care.

Application of HLA molecular level mismatching in ethnically diverse kidney transplant recipients receiving a steroid-sparing immunosuppression protocol.

Defining HLA mismatch at the molecular compared with the antigen level has been shown to be superior in predicting alloimmune responses, although data from across different patient populations are lacking. Using HLA-Matchmaker, HLA-EMMA and PIRCHE-II, this study reports on the association between molecular mismatch (MolMM) and de novo donor-specific antibody (dnDSA) in an ethnically diverse kidney transplant population receiving a steroid-sparing immunosuppression protocol. Of the 419 patients, 51 (12.2%) patients had dnDSA. De novo DSA were seen more frequently with males, primary transplants, patients receiving tacrolimus monotherapy, and unfavorably HLA-matched transplants. There was a strong correlation between MolMM load and antigen mismatch, although significant variation of MolMM load existed at each antigen mismatch. MolMM loads differed significantly by recipient ethnicity, although ethnicity alone was not associated with dnDSA. On multivariate analysis, increasing MolMM loads associated with dnDSA, whereas antigen mismatch did not. De novo DSA against 8 specific epitopes occurred at high frequency; of the 51 patients, 47 (92.1%) patients with dnDSA underwent a pretreatment biopsy, with 21 (44.7%) having evidence of alloimmune injury. MolMM has higher specificity than antigen mismatching at identifying recipients who are at low risk of dnDSA while receiving minimalist immunosuppression. Immunogenicity consideration is important, with more work needed on identification, especially across different ethnic groups.

Unique report of iliocaval endovascular reconstruction successfully enabling a kidney transplant.

Patients with end-stage renal disease and iliocaval venous obstruction are normally nonviable recipients of kidney transplantation. We report a case of a 34-year-old male patient who has been receiving hemodialysis as renal replacement therapy for 6 years due to immunoglobulin A nephropathy. Past medical history included multiple central venous catheter infections and catheter-associated thrombosis. Iliac confluence and inferior vena cava occlusion previously excluded the patient from the renal transplantation list. The exhaustion of venous access sites was already documented. After multidisciplinary discussion, the patient was proposed for endovascular iliocaval reconstruction aiming for a future kidney transplant. Iliocaval recanalization was achieved through bilateral femoral access. Inferior vena cava and iliac angioplasty were performed. A dedicated venous stent was deployed in the inferior vena cava, followed by a double-barrel reconstruction of the iliac confluence. Successful iliocaval recanalization was accomplished. Five months after kidney transplantation was performed with a deceased donor graft in the right iliac fossa. The postoperative period was uneventful. After 12 months, the patient remained free from kidney replacement therapies with a serum creatinine level of 1.3 mg/dL. To the best of our knowledge, this is the first clinical description of a successful kidney transplant in a patient with a previous iliocaval reconstruction.

Obesity, organ failure, and transplantation: A review of the role of metabolic and bariatric surgery in transplant candidates and recipients.

Obesity is a risk factor for kidney, liver, heart, and pulmonary diseases, as well as failure. Solid organ transplantation remains the definitive treatment for the end-stage presentation of these diseases. Among many criteria for organ transplant, efficient management of obesity is required for patients to acquire transplant eligibility. End-stage organ failure and obesity are 2 complex pathologies that are often entwined. Metabolic and bariatric surgery before, during, or after organ transplant has been studied to determine the long-term effect of bariatric surgery on transplant outcomes. In this review, a multidisciplinary group of surgeons from the Society of American Gastrointestinal and Endoscopic Surgeons and the American Society for Transplant Surgery presents the current published literature on metabolic and bariatric surgery as a therapeutic option for patients with obesity awaiting solid organ transplantation. This manuscript details the most recent recommendations, pharmacologic considerations, and psychological considerations for this specific cohort of patients. Since level one evidence is not available on many of the topics covered by this review, expert opinion was implemented in several instances. Additional high-quality research in this area will allow for better recommendations and, therefore, treatment strategies for these complex patients.

Defining pre-emptive living kidney donor transplantation as a quality indicator.

Quality indicators in kidney transplants are needed to identify care gaps and improve access to transplants. We used linked administrative health care databases to examine multiple ways of defining pre-emptive living donor kidney transplants, including different patient cohorts and censoring definitions. We included adults from Ontario, Canada with advanced chronic kidney disease between January 1, 2013, to December 31, 2018. We created 4 unique incident patient cohorts, varying the eligibility by the risk of progression to kidney failure and whether individuals had a recorded contraindication to kidney transplant (eg, home oxygen use). We explored the effect of 4 censoring event definitions. Across the 4 cohorts, size varied substantially from 20 663 to 9598 patients, with the largest reduction (a 43% reduction) occurring when we excluded patients with ≥1 recorded contraindication to kidney transplantation. The incidence rate (per 100 person-years) of pre-emptive living donor kidney transplant varied across cohorts from 1.02 (95% CI: 0.91-1.14) for our most inclusive cohort to 2.21 (95% CI: 1.96-2.49) for the most restrictive cohort. Our methods can serve as a framework for developing other quality indicators in kidney transplantation and monitoring and improving access to pre-emptive living donor kidney transplants in health care systems.