Hospitalization and survival of solid organ transplant recipients with coronavirus disease 2019: A propensity matched cohort study.

BACKGROUND: Solid organ transplant (SOT) recipients are predicted to have worse COVID-19 outcomes due to their compromised immunity. However, this association remains uncertain because published studies have had small sample sizes and variability in chronic comorbidity adjustment. METHODS: In this retrospective cohort study conducted at a multihospital health system, we compared COVID-19 outcomes and survival up to 60 days following hospital admission in SOT recipients taking baseline immunosuppressants versus hospitalized control patients. RESULTS: The study included 4,562 patients who were hospitalized with COVID-19 (108 SOT recipients and 4,454 controls) from 03/2020 to 08/2020. Mortality at 60 days was higher for SOT recipients (17% SOT vs 10% control; unadjusted odds ratio (OR) = 1.74, 95% confidence interval (CI) 1.04-2.91, P = 0.04). We then conducted a 1:5 propensity matched cohort analysis (100 SOT recipients; 500 controls) using age, sex, race, body mass index, hypertension, diabetes, chronic kidney disease, liver disease, admission month, and area deprivation index. Within 28 days of admission, SOT recipients had fewer hospital-free days (median; 17 SOT vs 21 control; OR = 0.64, 95%CI 0.46-0.90, P = 0.01) but had similar ICU-free days (OR = 1.20, 95%CI 0.72-2.00, P = 0.49) and ventilator-free days (OR = 0.91, 95%CI 0.53-1.57, P = 0.75). There was no statistically significant difference in 28-day mortality (9% SOT vs 12% control; OR = 0.76, 95%CI 0.36-1.57, P = 0.46) or 60-day mortality (16% SOT vs 14% control; OR = 1.15, 95%CI 0.64-2.08, P = 0.64). CONCLUSIONS: Hospitalized SOT recipients appear to need additional days of hospital care but can achieve short-term mortality outcomes from COVID-19 that are similar to non-SOT recipients in a propensity matched cohort study.

Predicting a Positive Antibody Response After 2 SARS-CoV-2 mRNA Vaccines in Transplant Recipients: A Machine Learning Approach With External Validation.

BACKGROUND: Solid organ transplant recipients (SOTRs) are less likely to mount an antibody response to SARS-CoV-2 mRNA vaccines. Understanding risk factors for impaired vaccine response can guide strategies for antibody testing and additional vaccine dose recommendations. METHODS: Using a nationwide observational cohort of 1031 SOTRs, we created a machine learning model to explore, identify, rank, and quantify the association of 19 clinical factors with antibody responses to 2 doses of SARS-CoV-2 mRNA vaccines. External validation of the model was performed using a cohort of 512 SOTRs at Houston Methodist Hospital. RESULTS: Mycophenolate mofetil use, a shorter time since transplant, and older age were the strongest predictors of a negative antibody response, collectively contributing to 76% of the model's prediction performance. Other clinical factors, including transplanted organ, vaccine type (mRNA-1273 versus BNT162b2), sex, race, and other immunosuppressants, showed comparatively weaker associations with an antibody response. This model showed moderate prediction performance, with an area under the receiver operating characteristic curve of 0.79 in our cohort and 0.67 in the external validation cohort. An online calculator based on our prediction model is available at http://transplantmodels.com/covidvaccine/ . CONCLUSIONS: Our machine learning model helps understand which transplant patients need closer follow-up and additional doses of vaccine to achieve protective immunity. The online calculator based on this model can be incorporated into transplant providers' practice to facilitate patient-centric, precision risk stratification and inform vaccination strategies among SOTRs.

mTOR inhibitors, mycophenolates, and other immunosuppression regimens on antibody response to SARS-CoV-2 mRNA vaccines in solid organ transplant recipients.

A recent study concluded that SARS-CoV-2 mRNA vaccine responses were improved among transplant patients taking mTOR inhibitors (mTORi). This could have profound implications for vaccine strategies in transplant patients; however, limitations in the study design raise concerns about the conclusions. To address this issue more robustly, in a large cohort with appropriate adjustment for confounders, we conducted various regression- and machine learning-based analyses to compare antibody responses by immunosuppressive agents in a national cohort (n = 1037). MMF was associated with significantly lower odds of positive antibody response (aOR = 0.09 0.130.18 ). Consistent with the recent mTORi study, the odds tended to be higher with mTORi (aOR = 1.00 1.452.13 ); however, importantly, this seemingly protective tendency disappeared (aOR = 0.47 0.731.12 ) after adjusting for MMF. We repeated this comparison by combinations of immunosuppression agents. Compared to MMF + tacrolimus, MMF-free regimens were associated with higher odds of positive antibody response (aOR = 2.39 4.267.92 for mTORi+tacrolimus; 2.34 5.5415.32 for mTORi-only; and 6.78 10.2515.93 for tacrolimus-only), whereas MMF-including regimens were not, regardless of mTORi use (aOR = 0.81 1.542.98 for MMF + mTORi; and 0.81 1.512.87 for MMF-only). We repeated these analyses in an independent cohort (n = 512) and found similar results. Our study demonstrates that the recently reported findings were confounded by MMF, and that mTORi is not independently associated with improved vaccine responses.

Early humoral immune response to two doses of severe acute respiratory syndrome coronavirus 2 vaccine in a diverse group of solid organ transplant candidates and recipients.

Response to two doses of a nucleoside-modified messenger ribonucleic acid (mRNA) vaccine was evaluated in a large solid-organ transplant program. mRNA COVID-19 vaccine was administered to transplant candidates and recipients who met study inclusion criteria. Qualitative anti-SARS-CoV-2 Spike Total Immunoglobulin (Ig) and IgG-specific assays, and a semi-quantitative test for anti-SARS-CoV-2 Spike protein IgG were measured in 241 (17.2%) transplant candidates and 1163 (82.8%) transplant recipients; 55.2% of whom were non-Hispanic White and 44.8% identified as another race. Transplant recipients were a median (IQR) of 3.2 (1.1, 6.8) years from transplantation. Response differed by transplant status: 96.0% versus 43.2% by the anti-SARS-CoV-2 Total Ig (candidates vs. recipients, respectively), 93.5% versus 11.6% by the anti-SARS-CoV-2 IgG assay, and 91.9% versus 30.1% by anti-spike titers after two doses of vaccine. Multivariable analysis revealed candidates had higher likelihood of response versus recipients (odds ratio [OR], 14.6; 95 %CI 2.19, 98.11; P = .02). A slightly lower response was demonstrated in older patients (OR .96; 95 %CI .94, .99; P = .002), patients taking antimetabolites (OR, .21; 95% CI .08, .51; P = .001). Vaccination prior to transplantation should be encouraged.

Risk Factors Associated With an Impaired Antibody Response in Kidney Transplant Recipients Following 2 Doses of the SARS-CoV-2 mRNA Vaccine.

BACKGROUND: Data about vaccine efficacy in solid organ transplant patients are limited. We previously reported our initial observation of a 6.2% immunogenicity rate in kidney transplant recipients (KTRs) after administration of 1 dose of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mRNA vaccine. We sought to report our observations of anti-SARS-CoV-2 antibody in KTRs after 2 doses of the SARS-CoV-2 mRNA vaccine. METHODS: We identified 105 KTRs who received 2 doses of the Pfizer-BioNTech or Moderna mRNA-1273 vaccine per availability and had anti-SARS-CoV-2 labs obtained at least 2 wk following administration of the second dose. Antibody testing was performed using 3 clinically validated qualitative and semiquantitative assays. RESULTS: KTRs had a 36.2% antibody response rate, whereas an age ≥68 years and a longer time from transplant were factors associated with antibody response. CONCLUSIONS: The low antibody response in KTRs may be associated with the immunosuppressive state. More data are needed to evaluate if KTRs may require higher vaccine doses or an additional booster dose to increase their ability to mount an immune response to the SARS-CoV-2 vaccine.

Neurogenic Orthostatic Hypotension: a Common Complication of Successful Pancreas Transplantation.

BACKGROUND: Orthostatic hypotension (OH) is a poorly understood complication of simultaneous pancreas-kidney (SPK) transplantation. We sought to determine the incidence, timing, and relationship of OH to rapid glycemic control in the early posttransplant period. METHODS: This was a nonrandomized retrospective single-center review of 75 SPK and 19 kidney-alone (KA) recipients with type 1 diabetes (DM). RESULTS: OH occurred in 57 (76%) SPK versus 2 (10%) KA recipients (odds ratio [OR] 61.72, 95% confidence interval [CI], 9.69-393.01; P < 0.001). The median onset of OH was 12 (interquartile range [IQR] 9-18) days posttransplant and resolved in 85% of SPK recipients after a median of 2.5 (IQR 1.2-6.3) months. Among SPK recipients, independent risk factors for OH were a shorter duration of DM (OR 0.85, 95% CI, 0.73-0.98; P = 0.03) and rapid glycemic control in the early posttransplant period (OR 1.13, 95% CI, 1.01-1.27; P = 0.04), as evidenced by a larger percent change in hemoglobin A1c (HbA1c) from transplant to month 3. OH patients had a higher median baseline HbA1c [8.3% (IQR 7.2-10.0) versus 7.1% (IQR 6.8-8.3); P = 0.07], lower median 3-month HbA1c [4.8% (IQR 4.6-5.2) versus 5.2% (IQR 5.0-5.4); P = 0.02], and a larger reduction in HbA1c over time as compared to recipients without OH (P < 0.01). CONCLUSIONS: Our results show that OH is more likely to occur following SPK versus KA transplantation and is strongly associated with rapid glucose normalization within the early posttransplant period.

Long-Term Follow-Up of Renal Transplant Recipients Treated With IVIG for De Novo Donor-Specific Antibodies.

BACKGROUND: Renal allograft survival is negatively affected by the development of de novo posttransplant donor-specific antibodies (dnDSA). We sought to determine whether treatment with intravenous immunoglobulin (IVIG) could remove or reduce the intensity of dnDSA. METHODS: A single-center study of 12 recipients with dnDSA and stable function who received IVIG 1 g/kg monthly for 6 months were compared with a contemporaneous cohort of 24 recipients with dnDSA who did not receive IVIG. RESULTS: The median time to first dnDSA was 6 months (interquartile range [IQR], 1-12), and follow-up was 83 months (IQR, 58-94) posttransplant. Resolution of dnDSA occurred in 27% of IVIG vs 46% of control recipients (P = .48). Fifty-eight percent of recipients in both cohorts demonstrated a reduction in the intensity of the dominant DSA at last follow-up (P =1.0). A reduction in the number of dnDSAs occurred in 58% vs 62% of the IVIG and control cohorts, respectively (P = .81). Post-dnDSA, acute rejection occurred in 8% of the IVIG vs 42% in the control group (P = .06). Forty-two percent of IVIG-treated vs 49% of control recipients had a deterioration in function from first dnDSA until most recent follow-up (P = .81). Actuarial graft survivals were equivalent between groups. CONCLUSIONS: IVIG treatment of dnDSA in recipients with stable graft function had no impact on DSA clearance or MFI reduction, but this outcome may also be owing to sample size. Larger studies or alternate dosing regimens may be required to determine if there is any role for the use of IVIG as a treatment for dnDSA.

Delayed Implantation of Pumped Kidneys Decreases Renal Allograft Futility in Combined Liver-Kidney Transplantation.

BACKGROUND: Combined liver-kidney transplantation (CLKT) improves survival for liver transplant recipients with renal dysfunction; however, the tenuous perioperative hemodynamic and metabolic milieu in high-acuity CLKT recipients increases delayed graft function and kidney allograft failure. We sought to analyze whether delayed KT through pumping would improve kidney outcomes following CLKT. METHODS: A retrospective analysis (University of California Los Angeles [n = 145], Houston Methodist Hospital [n = 79]) was performed in all adults receiving CLKT at 2 high-volume transplant centers from February 2004 to January 2017, and recipients were analyzed for patient and allograft survival as well as renal outcomes following CLKT. RESULTS: A total of 63 patients (28.1%) underwent delayed implantation of pumped kidneys during CLKT (dCLKT) and 161 patients (71.9%) received early implantation of nonpumped kidneys during CLKT (eCLKT). Most recipients were high-acuity with median biologic model of end-stage liver disease (MELD) score of, 35 for dCLKT and 34 for eCLKT (P = ns). Pretransplant, dCLKT had longer intensive care unit stay, were more often intubated, and had greater vasopressor use. Despite this, dCLKT exhibited improved 1-, 3-, and 5-year patient and kidney survival (P = 0.02) and decreased length of stay (P = 0.001), kidney allograft failure (P = 0.012), and dialysis duration (P = 0.031). This reduced kidney allograft futility (death or continued need for hemodialysis within 3 mo posttransplant) for dCLKT (6.3%) compared with eCLKT (19.9%) (P = 0.013). CONCLUSIONS: Delayed implantation of pumped kidneys is associated with improved patient and renal allograft survival and decreased hospital length of stay despite longer kidney cold ischemia. These data should inform the ethical debate as to the futility of performing CLKT in high-acuity recipients.

Early Experience With COVID-19 and Solid Organ Transplantation at a US High-volume Transplant Center.

BACKGROUND: The novel coronavirus severe acute respiratory syndrome coronavirus 2 [coronavirus disease 2019 (COVID-19)] poses unique challenges for immunosuppressed patients. Solid organ transplant (SOT) recipients comprise a large proportion of this group, yet there is limited knowledge about the presentation, clinical course, and immunosuppression management of this novel infection among heart, lung, liver, pancreas, and kidney transplant recipients. METHODS: We present 21 SOT recipients diagnosed with COVID-19 between January 1, 2020 and April 22, 2020 at a US high-volume transplant center. Diagnostic workup, clinical course, immunosuppression/antiviral management, and immediate outcomes are described. RESULTS: Twenty-one (15.9%) of 132 symptomatic patients tested were positive. Mean age at diagnosis was 54.8 ± 10.9 y. Median time from transplant was 5.58 y (interquartile range 2.25, 7.33). Median follow-up was 18 d (interquartile range 13, 30). Fourteen patients required inpatient management, with 7 (50%) placed in the intensive care unit (ICU). All transplant types were represented. Nearly 43% exhibited GI symptoms. Over half (56.2%) presented with elevated serum creatinine suggestive of acute kidney injury. The majority of patients (5/7) with concomitant infections at baseline required the ICU. Eighty percent received hydroxychloroquine ± azithromycin. Ten received toclizumab and/or ribavirin; 1 received remdesivir. Antimetabolites ± calcineurin inhibitors were held or reduced. Over half of hospitalized patients (8/14) were discharged home. Only 1 mortality (4.8%) to date, in a critically ill heart/kidney patient who had been in the ICU before diagnosis. CONCLUSIONS: COVID-19 positive SOT at our institution had favorable short-term outcomes. Those with concomitant infections had more severe illness. More data will be available to evaluate long-term outcomes and disease impact on graft function.

Assessment of infectious complications in elderly kidney transplant recipients receiving induction with anti-thymocyte globulin vs basiliximab.

BACKGROUND: Elderly transplant recipients experience lower rates of acute rejection with higher rates of infectious complications compared to their younger counterparts. While less intensive immunosuppression may be preferable, there are no recommendations for depleting versus non-depleting induction strategies. We sought to compare infectious complications between anti-thymocyte globulin (ATG) and basiliximab (IL2RA) induction in elderly kidney transplant recipients (KTRs). METHODS: We reviewed 146 KTRs ≥65 years receiving ATG or IL2RA induction. Per institution protocol, ATG was administered to patients with the following characteristics, irrespective of age: African American (AA), PRA ≥20%, and/or re-transplantation. Infectious complications (bacterial, viral, and invasive fungal) at 1 year were compared. RESULTS: There were significantly more AA, deceased donors, and sensitized KTRs in the ATG group, reflecting criteria for induction agent. ATG KTRs experienced higher rates of overall infectious complications (77% vs 56%, P = .01), driven by increased bacterial (54% vs 39%, P = .08) and viral infections (51% vs 35%, P = .05). Urinary tract infections (UTIs) and CMV in particular occurred at high rates among ATG patients (46% and 32%, respectively). In multivariate analysis, the only independent risk factor associated with increased risk for infection was induction with ATG (adjusted HR 1.71 [95% CI 1.04-2.83], P = .04). Overall rates of immunologic outcomes were low. CONCLUSION: Elderly KTRs receiving ATG are at an increased risk for infectious complications, largely attributed to high rates of UTIs and CMV. Additional strategies aimed at mitigating these complications in elderly patients requiring ATG may be beneficial.

Weight Gain After Simultaneous Kidney and Pancreas Transplantation.

BACKGROUND: Excessive weight (EW) gain is common after solid organ transplantation, but there is little information concerning obesity after pancreas transplantation. The study goal was to characterize EW gain after kidney-pancreas (KP) transplantation. METHODS: This was a retrospective single-center review of 100 KP recipients transplanted between September 2007 and June 2015. RESULTS: The median percent weight gain for all recipients at 1 year posttransplant was 10% (interquartile range, 2.7%-19.3%) of baseline weight. EW gain, defined as greater than or equal to a 19% 1-year increase in weight, included all recipients (n = 26) above the upper limit of interquartile range for weight gain at 1 year. In multivariate analysis, recipient age <40 years, the use of tacrolimus/mammalian target of rapamycin immunosuppression, and an acute rejection event were independent risk factors for EW gain. At a mean follow-up of 43±23 months, there was no difference in patient or graft survival between the EW and non-EW cohorts. Although mean hemoglobin A1c levels between groups were equivalent, the EW versus non-EW cohort displayed a significant increase in mean insulin levels and a trend towards higher C-peptide levels. Criteria for posttransplant metabolic syndrome was met in 34.6% of EW versus 17.6% of non-EW cohorts (P = 0.07). CONCLUSIONS: At intermediate-term follow-up, EW gain after KP transplantation was not associated with an increased risk of death or graft loss, although there was a trend toward a greater risk of posttransplant metabolic syndrome. There may be a metabolic consequence of successful pancreas transplantation that results in EW gain in a proportion of recipients, leading to an increased risk of long-term cardiovascular complications.

Cross-sectional evaluation of the relationship between vitamin D status and supplement use across levels of kidney function in adults.

OBJECTIVES: The objective of this study was to assess vitamin D status of US non-pregnant adults using a standardised assay across 15 mL/min/1.73 m2 increments of kidney function, report the use of dietary supplements containing vitamin D and assess relationships between vitamin D and markers of bone resorption. DESIGN: This study is a cross-sectional evaluation. SETTING: The study is from the US National Health and Nutrition Evaluation Survey in 2001-2012. PARTICIPANTS: The participants were non-institutionalised, non-pregnant adults, age ≥20 years. PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcome measure was serum 25OHD evaluated using liquid chromatography-tandem mass spectroscopy traceable to international reference standards. Secondary outcome measures were use of dietary supplements containing vitamin D and the serum intact parathyroid hormone and bone-specific alkaline phosphatase in a subset of participants. RESULTS: The median 25OHD concentration in 27 543 US non-pregnant adults was 25.7 ng/mL (range, 2.2-150.0 ng/mL). Vitamin D supplements were used by 38.0%; mean (SE)=757 (43) international units/day. The range of 25OHD concentration across groups, stratified by kidney function, was 23.0-28.1 ng/mL. The lowest concentration of 25OHD observed was in people with higher kidney function (23.0 ng/mL for estimated glomerular filtration rate >105 mL/min/1.73 m2). Only 24% of people not taking a dietary supplement had a 25OHD concentration >30 ng/mL. Serum intact parathyroid hormone inversely correlated with 25OHD within all kidney function groups. Bone-specific alkaline phosphatase was also negatively associated with 25OHD concentration. CONCLUSIONS: These data indicate that 25OHD concentrations and supplement use may be suboptimal in a significant proportion of the population, across all kidney function levels. The response of bone resorption markers further suggests that 25OHD levels could be improved. Together, these data support a re-evaluation of the 25OHD concentration associated with health in adults.

Ciprofloxacin for BK viremia prophylaxis in kidney transplant recipients: Results of a prospective, double-blind, randomized, placebo-controlled trial.

In kidney transplantation, BK virus infection has historically resulted in high rates of graft dysfunction and graft loss. Unlike other opportunistic infections, no therapies have been shown to prevent BK. The purpose of the current study was to evaluate the safety and efficacy of ciprofloxacin for the prevention of BK viremia in kidney transplant recipients. Two hundred kidney transplant recipients were enrolled in a prospective, randomized, double-blind, placebo-controlled trial comparing a 3-month course of ciprofloxacin (n = 133) vs placebo (n = 67) for the prevention of BK viremia. The primary endpoint of BK viremia at month 6 posttransplant occurred in 25 (18.8%) patients in the ciprofloxacin group and 5 (7.5%) in the placebo group (P = .03). Higher rates of BK viremia (23.3% vs 11.9%; P = .06) and BK nephropathy (5.8% vs 1.5%; P = .26) remained at 12 months in the ciprofloxacin group. Ciprofloxacin use was associated with a significantly higher rate of fluoroquinolone-resistant gram-negative infections (83.3% vs 50%; P = .04). A 3-month course of ciprofloxacin was ineffective at preventing BK viremia in kidney transplant recipients and was associated with an increased risk of fluoroquinolone-resistant infections. Clinical trial registration number: NCT01789203.

Unexplained fever after pancreas transplantation.

BACKGROUND: Fever occurs frequently early after pancreas transplant, however, the exact cause is often undetermined. Limited data are available on pancreas recipients experiencing unexplained, noninfectious fever. This study aims to characterize unexplained fever (UF) in pancreas recipients and its effect on patient and graft outcomes. METHODS: We performed a retrospective cohort study of UF among consecutive pancreas or simultaneous pancreas-kidney transplant recipients from 1 January 2011 to 31 August 2015. Classification of UF was based on the absence of positive cultures, radiologic findings, and other diagnostic features of infection or rejection. RESULTS: Twenty-three of 92 (25%) patients experienced UF. The UF episode first occurred at a mean of 31 ± 17 days post-transplant and accounted for 34 admissions with an average length of stay of 5.1 ± 3.4 days. Intravenous corticosteroid was administered following confirmation of negative diagnostic tests in 77% of patients, with fever resolution occurring in all. No differences were seen in rates of biopsy-proven rejection, graft loss, death, or documented infections compared to UF-free patients during the first-year post-transplant. CONCLUSION: UF is a common cause for readmission following pancreas transplantation. While the etiology of UF remains difficult to identify, UF occurrence was not associated with adverse outcomes during the first-year post-transplant.

Short- and midterm results for internal jugular vein extension for short right renal vein kidney transplant.

Renal transplantation remains the definitive treatment for end-stage renal disease (ESRD). The shorter renal vein in right donor nephrectomies is associated with higher incidence of technical failure. We present here our experience with autologous internal jugular vein (IJV) conduits to facilitate living-donor transplants. Six patients underwent right, living-donor kidney transplant with simultaneous IJV harvest over a 1-year period. All had bilateral jugular duplex scans preoperatively and were placed on aspirin 81 mg postoperatively. Patient demographics, comorbidities, and laboratories were retrospectively queried. Postoperative follow-up and examination were performed per institutional protocol. The mean age and BMI were 51 ± 4.6 years and 30 ± 1.4 kg/m2 , respectively. An average 4.5 ± 0.5 cm of IJV was taken, and anastomosed exsitu, end to end to the renal vein. One patient developed a perinephric hematoma requiring reexploration and another expired during follow-up from septic shock of unknown etiology; there were no harvest site complications or deep vein thrombosis. All had immediate and stable graft function at 3.8 ± 1.7 (range: 0.7-11.3) months follow-up. Mean serum creatinine and estimated glomerular filtration rate were 1.3 ± 0.1 mg/dL and 55 ± 2.4 mL/min/1.73 m2 , respectively. Internal jugular vein extension of short right renal veins for kidney transplant is a viable technique for ESRD patients with promising results.

Conversion from tacrolimus-mycophenolate mofetil to tacrolimus-mTOR immunosuppression after kidney-pancreas transplantation reduces the incidence of both BK and CMV viremia.

BACKGROUND: We sought to determine whether conversion from tacrolimus/mycophenolate mofetil (TAC-MMF) into tacrolimus/mTOR inhibitor (TAC-mTOR) immunosuppression would reduce the incidences of BK and CMV viremia after kidney/pancreas (KP) transplantation. METHODS: In this single-center review, the TAC-mTOR cohort (n = 39) was converted at 1 month post-transplant to an mTOR inhibitor and reduced-dose tacrolimus. Outcomes were compared to a cohort of KP recipients (n = 40) maintained on TAC-MMF. RESULTS: At 3 years post-transplant, KP survivals and incidences of kidney/pancreas rejection were equivalent between mTOR and MMF-treated cohorts. (P = ns). BK viremia-free survival was better for the mTOR vs MMF-treated group (P = .004). In multivariate analysis, MMF vs mTOR immunosuppression was an independent risk factor for BK viremia (hazard ratio 12.27, P = .02). Similarly, mTOR-treated recipients displayed better CMV infection-free survival compared to the MMF-treated cohort (P = .01). MMF vs mTOR immunosuppression (hazard ratio 18.77, P = .001) and older recipient age (hazard ratio 1.13 per year, P = .006) were independent risk factors for CMV viremia. Mean estimated GFR and HgbA1c levels were equivalent between groups at 1, 2, and 3 years post-transplantation. CONCLUSION: Conversion from TAC/MMF into TAC/mTOR immunosuppression after KP transplantation reduced the incidences of BK and CMV viremia with an equivalent risk of acute rejection and similar renal/pancreas function.

Belatacept conversion in an HIV-positive kidney transplant recipient following anti-thymocyte globulin induction.

Herein, we describe a case of early belatacept conversion in a human immunodeficiency virus (HIV)-positive kidney transplant recipient in an effort to improve suboptimal graft function and avoid drug interactions following anti-thymocyte globulin (ATG) administration. We observed improvement in renal function without HIV disease progression or opportunistic infections. Donor-specific antibodies appeared shortly after conversion but cleared without intervention. This case highlights belatacept as a means to improve renal function and avoid significant drug interactions even following ATG induction.

Early clearance vs persistence of de novo donor-specific antibodies following lung transplantation.

BACKGROUND: The natural history of de novo donor-specific antibodies (dnDSA) after lung transplantation is not well-described. We sought to determine the incidence and risk factors associated with dnDSA and compare outcomes between recipients with transient (or isolated) vs persistent dnDSA after transplantation. METHODS: A single-center review of all lung transplants from 1/2009-7/2013. DSAs were tested eight times in the first year and every 4 months thereafter. Outcomes examined included acute rejection and graft failure. RESULTS: Median follow-up was 18 months (range: 1-61 months), and 24.6% of 333 first-time lung-only transplant recipients developed a dnDSA. Ethnicity, HLA-DQ mismatches, post-transplantation platelet transfusion and Lung Allocation Score >60 were associated with dnDSA (P<.05). Overall graft survival was worse for dnDSA-positive vs negative recipients (P=.025). Of 323 recipients with 1-year follow-up, 72 (22.2%) developed dnDSA, and in 25 (34.7%), the dnDSA was transient and cleared. Recipients with transient dnDSA were less likely to develop acute rejection than those with persistent dnDSA (P=.007). CONCLUSIONS: Early post-lung transplantation, dnDSA occurred in 1/4 of recipients, was associated with peri-transplant risk factors and resulted in decreased survival. Spontaneous clearance of dnDSA, seen in one-third of recipients, was associated with a lower risk of acute rejection.