A paired-kidney allocation study found superior survival with HLA-DR compatible kidney transplants in the Eurotransplant Senior Program.

The Eurotransplant Senior Program (ESP) has expedited the chance for elderly patients with kidney failure to receive a timely transplant. This current study evaluated survival parameters of kidneys donated after brain death with or without matching for HLA-DR antigens. This cohort study evaluated the period within ESP with paired allocation of 675 kidneys from donors 65 years and older to transplant candidates 65 years and older, the first kidney to 341 patients within the Eurotransplant Senior DR-compatible Program and 334 contralateral kidneys without (ESP) HLA-DR antigen matching. We used Kaplan-Meier estimates and competing risk analysis to assess all cause mortality and kidney graft failure, respectively. The log-rank test and Cox proportional hazards regression were used for comparisons. Within ESP, matching for HLA-DR antigens was associated with a significantly lower five-year risk of mortality (hazard ratio 0.71; 95% confidence interval 0.53-0.95) and significantly lower cause-specific hazards for kidney graft failure and return to dialysis at one year (0.55; 0.35-0.87) and five years (0.73; 0.53-0.99) post-transplant. Allocation based on HLA-DR matching resulted in longer cold ischemia (mean difference 1.00 hours; 95% confidence interval: 0.32-1.68) and kidney offers with a significantly shorter median dialysis vintage of 2.4 versus 4.1 yrs. in ESP without matching. Thus, our allocation based on HLA-DR matching improved five-year patient and kidney allograft survival. Hence, our paired allocation study suggests a superior outcome of HLA-DR matching in the context of old-for-old kidney transplantation.

[Pancreas transplantation-clinic, technique, and histological assessment]. / Pankreastransplantation ­ Klinik, Technik und histologische Beurteilung.

BACKGROUND: In Germany pancreas transplants are performed in only a few selected and specialized centres, usually combined with a kidney transplant. Knowlegde of the indications for and techniques of transplantation as well as of the histopathological assessment for rejection in pancreas and duodenal biopsies is not very widespread. AIM: To give an overview of the development and status quo in pancreas-kidney-transplantation in Germany summarizing the experience of the largest German pancreas transplant centre and to give a résumé of the results of histological diagnoses of biopsy specimens submitted between 06/2017 and 12/2020. Moreover, a detailed description and illustration of histological findings is included. MATERIAL AND METHODS: A thorough literature search for aspects of the history, technique and indication for pancreas transplantation was performed and discussed in the context of the local experience and technical particularities specific for the transplant centre in Bochum. The occurrence of complications was compared with international reports. Results of pancreas and duodenal biopsies submitted to Erlangen between 06/2017 and 12/2020 for histological evaluation, which were evaluated according to the Banff classification, were summarized. For a better understanding key histological findings of pancreas rejection and differential diagnoses were illustrated and discussed. RESULTS: A total of 93 pancreas transplant specimens and 3 duodenal biopsies were included. 34.4% of pancreas specimens did not contain representative material for a diagnosis. In the remaining 61 biopsies 24.6% showed no rejection, 62.3% were diagnosed with acute T-cell mediated rejection (TCMR) and 8.2% with signs suspicious of antibody-mediated rejection (ABMR). Acute acinary epithelial injury was seen in 59%, pancreatitis in 8.2% and allograft fibrosis was reported in as many as 54.1%. Calcineurin-inhibitor toxicity was discussed in only 4.9%. CONCLUSION: Pancreas-kidney-transplantation and standardized histological assessment of the transplanted pancreas or rarely duodenum with reporting according to the updated Banff classification of pancreas transplants or previous reports of duodenal rejection are important mainstays in the management of patients with diabetes.

Immune monitoring facilitates the clinical decision in multifocal COVID-19 of a pancreas-kidney transplant patient.

The optimal management in transplant recipients with coronavirus disease 2019 (COVID-19) remains uncertain. The main concern is the ability of immunosuppressed patients to generate sufficient immunity for antiviral protection. Here, we report on immune monitoring facilitating a successful outcome of severe severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-associated pneumonia, meningoencephalitis, gastroenteritis, and acute kidney and pancreas graft failure in a pancreas-kidney transplant recipient. Despite the very low numbers of circulating B, NK, and T cells identified in follow-up, a strong SARS-CoV-2 reactive T cell response was observed. Importantly, we detected T cells reactive to Spike, Membrane, and Nucleocapsid proteins of SARS-CoV-2 with majority of T cells showing polyfunctional proinflammatory Th1 phenotype at all analyzed time points. Antibodies against Spike protein were also detected with increasing titers in follow-up. Neutralization tests confirmed their antiviral protection. A correlation between cellular and humoral immunity was observed underscoring the specificity of demonstrated data. We conclude that analyzing the kinetics of nonspecific and SARS-CoV-2-reactive cellular and humoral immunity can facilitate the clinical decision on immunosuppression adjustment and allow successful outcome as demonstrated in the current clinical case. Although the antiviral protection of the detected SARS-CoV-2-reactive T cells requires further evaluation, our data prove an ability mounting a strong SARS-CoV-2-reactive T cell response with functional capacity in immunosuppressed patients.

Allograft infiltration and meningoencephalitis by SARS-CoV-2 in a pancreas-kidney transplant recipient.

Severe acute respiratory syndrome corona virus 2 (SARS-CoV-2) preferentially affects epithelia of the upper and lower respiratory tract. Thus, impairment of kidney function has been primarily attributed until now to secondary effects such as cytokine release or fluid balance disturbances. We provide evidence that SARS-CoV-2 can directly infiltrate a kidney allograft. A 69-year-old male, who underwent pancreas-kidney transplantation 13 years previously, presented to our hospital with coronavirus disease 2019 (COVID-19) pneumonia and impaired pancreas and kidney allograft function. Kidney biopsy was performed showing tubular damage and an interstitial mononuclear cell infiltrate. Reverse transcriptase polymerase chain reaction from the biopsy specimen was positive for SARS-CoV-2. In-situ hybridization revealed SARS-CoV-2 RNA in tubular cells and the interstitium. Subsequently, he had 2 convulsive seizures. Magnetic resonance tomography suggested meningoencephalitis, which was confirmed by SARS-CoV-2 RNA transcripts in the cerebrospinal fluid. The patient had COVID-19 pneumonia, meningoencephalitis, and nephritis. SARS-CoV-2 binds to its target cells through angiotensin-converting enzyme 2, which is expressed in a broad variety of tissues including the lung, brain, and kidney. SARS-CoV-2 thereby shares features with other human coronaviruses including SARS-CoV that were identified as pathogens beyond the respiratory tract as well. The present case should provide awareness that extrapulmonary symptoms in COVID-19 may be attributable to viral infiltration of diverse organs.

Impact of donor cardiopulmonary resuscitation on the outcome of simultaneous pancreas-kidney transplantation-a retrospective study.

Previous cardiac arrest in brain-dead donors has been discussed as a potential risk factor in pancreas transplantation (PT), leading to a higher rate of organ refusal. This study aimed to assess the impact of cardiopulmonary resuscitation (CPR) in brain-dead donors on pancreas transplant outcome. A total of 518 type 1 diabetics underwent primary simultaneous pancreas-kidney (SPK) transplantation at our center between 1994 and 2018. Patients were divided into groups, depending on whether their donor had been resuscitated or not. A total of 91 (17.6%) post-CPR donors had been accepted for transplantation (mean duration of cardiac arrest, 19.4 ± 15.6 min). Those donors were younger (P < 0.001), had lower pancreas donor risk index (PDRI, P = 0.003), and had higher serum creatinine levels (P = 0.021). With a median follow-up of 167 months (IQR 82-229), both groups demonstrated comparable short- and long-term patient and graft survival. The resuscitation time (<20 min vs. ≥20 min) also showed no impact, with similar survival rates for both groups. A multivariable Cox regression analysis suggested no statistically significant association between donor CPR and patient or graft survival. Our results indicate that post-CPR brain-dead donors are suitable for PT without increasing the risk of complications.

An open-label, randomized trial indicates that everolimus with tacrolimus or cyclosporine is comparable to standard immunosuppression in de novo kidney transplant patients.

This is a randomized trial (ATHENA study) in de novo kidney transplant patients to compare everolimus versus mycophenolic acid (MPA) with similar tacrolimus exposure in both groups, or everolimus with concomitant tacrolimus or cyclosporine (CsA), in an unselected population. In this 12-month, multicenter, open-label study, de novo kidney transplant recipients were randomized to everolimus with tacrolimus (EVR/TAC), everolimus with CsA (EVR/CsA) or MPA with tacrolimus (MPA/TAC), with similar tacrolimus exposure in both groups. Non-inferiority of the primary end point (estimated glomerular filtration rate [eGFR] at month 12), assessed in the per-protocol population of 338 patients, was not shown for EVR/TAC or EVR/CsA versus MPA/TAC. In 123 patients with TAC levels within the protocol-specified range, eGFR outcomes were comparable between groups. The mean increase in eGFR during months 1 to 12 post-transplant, analyzed post hoc, was similar with EVR/TAC or EVR/CsA versus MPA/TAC. The incidence of treatment failure (biopsy proven acute rejection, graft loss or death) was not significant for EVR/TAC but significant for EVR/CsA versus MPA/TAC. Most biopsy-proven acute rejection events in this study were graded mild (BANFF IA). There were no differences in proteinuria between groups. Cytomegalovirus and BK virus infection were significantly more frequent with MPA/TAC. Thus, everolimus with TAC or CsA showed comparable efficacy to MPA/TAC in de novo kidney transplant patients. Non-inferiority of renal function, when pre-specified, was not shown, but the mean increase in eGFR from month 1 to 12 was comparable to MPA/TAC.

A Valine Mismatch at Position 129 of MICA Is an Independent Predictor of Cytomegalovirus Infection and Acute Kidney Rejection in Simultaneous Pancreas⁻Kidney Transplantation Recipients.

The polymorphic major histocompatibility complex class I chain-related molecule A (MICA) and its soluble form (sMICA) interact with activating receptor natural-killer group 2 member D (NKG2D) on natural-killer (NK) and T cells, thereby modifying immune responses to transplantation and infectious agents (e.g., cytomegalovirus). Two single-nucleotide polymorphisms (SNPs), rs2596538GA in the MICA promoter and rs1051792AG in the coding region (MICA-129Val/Met), influence MICA expression or binding to NKG2D, with MICA-129Met molecules showing higher receptor affinity. To investigate the impact of these SNPs on the occurrence of cytomegalovirus infection or acute rejection (AR) in individuals who underwent simultaneous pancreas⁻kidney transplantation (SPKT), 50 recipient-donor pairs were genotyped, and sMICA levels were measured during the first year post-transplantation. Recipients with a Val-mismatch (recipient Met/Met and donor Val/Met or Val/Val) showed shorter cytomegalovirus infection-free and shorter kidney AR-free survival. Additionally, Val mismatch was an independent predictor of cytomegalovirus infection and kidney AR in the first year post-transplantation. Interestingly, sMICA levels were lower in rs2596538AA and MICA129Met/Met-homozygous recipients. These results provide further evidence that genetic variants of MICA influence sMICA levels, and that Val mismatch at position 129 increases cytomegalovirus infection and kidney AR risk during the first year post-SPKT.

125 Cases of duodenoduodenostomy in pancreas transplantation: a single-centre experience of an alternative enteric drainage.

Several exocrine drainage procedures have been successfully developed to perform pancreas transplantation (PT). Retroperitoneal graft placement allows exocrine drainage via direct duodenoduodenostomy (DD). This technique provides easy access for endoscopic surveillance and biopsy. A total of 241 PT procedures were performed in our centre between 2002 and 2012. DD was performed in 125 patients, and duodenojejunostomy (DJ) in 116 patients. We retrospectively compared our experience with these two types of enteric drainage, focusing on graft and patient survivals, as well as postoperative complications. With a mean follow-up of 59 months, both groups demonstrated comparable patient and graft survivals. 14 (11%) of 125 cases in the DD group and 21 (18%) of 116 cases in the DJ group had pancreatic graft loss (P = 0.142). Graft thrombosis [5 (4%) vs. 18 (16%) P = 0.002], anastomotic insufficiency [2 (1.6%) vs. 8 (7%) P = 0.052] and relaparotomy [52 (41%) vs. 56 (48%) P = 0.29] occurred more frequently in the DJ group, whereas gastrointestinal bleeding [14 (11%) vs. 4 (3%) P = 0.026] occurred more often in the DD group. DD is a feasible and safe technique in PT, with no increase in enteric complications. It is equivalent to other established techniques and extends the feasibility of anastomotic sites, especially in recipients who have undergone a second transplantation.

Fixed low dose versus concentration-controlled initial tacrolimus dosing with reduced target levels in the course after kidney transplantation: results from a prospective randomized controlled non-inferiority trial (Slow & Low study).

Background: Optimal initial tacrolimus dosing and early exposure of tacrolimus after renal transplantation is not well studied. Methods: In this open-label, 6 months, multicenter, randomized controlled, non-inferiority study, we randomly assigned 432 renal allograft recipients to receive basiliximab induction, mycophenolate and steroids and either standard prolonged-release tacrolimus (trough levels: 7-9 ng/ml; Standard Care arm), or an initial 7-day fixed 5 mg/day dose of prolonged-release tacrolimus followed by lower tacrolimus predose levels (trough levels: 5-7 ng/ml; Slow & Low arm). The primary end point was the combined incidence rate of biopsy-proven acute rejections (BPAR; including borderline), graft failure, or death at 6 months with a non-inferiority margin of 12.5%. (EudraCT-Nr: 2013-001770-19. Findings: The combined primary endpoint in the Slow & Low arm was non-inferior compared to the Standard Care arm (22.1% versus 20.7%; difference: 1.4%, 90% CI -5.5% to 8.3%). The overall rate of BPAR including borderlines was similar (Slow & Low 17.4% versus Standard Care 16.6%). Safety parameters such as delayed graft function, kidney function, donor specific HLA-antibodies, infections, or post-transplantation diabetes mellitus did not differ. Interpretation: This is the first study to show that an initial fixed dose of 5 mg per day followed by lower tacrolimus exposure is non-inferior compared to standard tacrolimus therapy and equally efficient and safe within 6 months after renal transplantation. These data suggest that therapeutic drug monitoring for prolonged release tacrolimus can be abandoned until start of the second week after transplantation. Funding: Investigator-initiated trial, financial support by Astellas Pharma GmbH.

Autotransplantation for the treatment of severe renal artery stenosis in a solitary kidney after repeated percutaneous transluminal angioplasty: a case report.

A 66-year-old female suffering from massive atherosclerosis with a long history of renal artery stenosis in the left solitary kidney was admitted to reevaluate an in-stent restenosis. Advanced peripheral arterial disease had formerly been treated by aortobifemoral bypass surgery and a highly eccentric infrarenal abdominal aortic stenosis of 70 - 80% had been treated by patch angioplasty. In this patient several percutaneous transluminal renal angioplasties after a former stent deployment had resulted in recurrent in-stent restenoses. The renal artery stenosis was reevaluated and a re-angioplasty attempt was unsuccessful due to technical failure. Blood pressure remained difficult to manage. Renal function decreased as a result of presumed acute renal failure. A further progression of the renal artery stenosis was found. Autotransplantation to the left iliac fossa was done, because aortorenal bypass was considered impossible. Renal function normalized and follow-up Doppler ultrasonography examinations revealed a newly developed ostial anastomotic stenosis of 60 - 70%. While medical therapy and percutaneous transluminal angioplasty with stent deployment are common treatment options, surgical interventions are reserved for cases of complex stenoses. Autotransplantation as a complex option in the treatment of renal artery stenosis seems to be an adequate alternative in patients with severe, generalized atherosclerosis after failure of interventional procedures and the impossibility of standard surgical techniques.

Long-term results of pancreas transplantation in patients older than 50 years.

Aging of the population and improvements in diabetes therapy have led to an increased number of older pancreas transplant candidates. The aim of our retrospective study was to evaluate pancreas transplantation (PT) outcomes in patients ≥ 50 years, as limited data exist in these patients. We analyzed 398 consecutive pancreas transplant patients from June 1994 to June 2009 for different outcomes (patient/graft survival, rejection rate, and surgical complications) between the age groups ≥ 50 years (n = 69) and <50 years (n = 329). Donor and recipient characteristics were similar except for recipient age (54.0 vs. 38.8 years), BMI (24.6 vs. 22.9 kg/m(2) ), and duration of diabetes mellitus (36.0 vs. 27.7 years). One-, 5-, and 10-year patient and graft (kidney/pancreas) survival were not significantly different between the groups with patient survival rates reaching 84% and pancreas graft survival up to 67% after 10 years. Surgical complications such as relaparotomy rate (34% vs. 33%) or pancreas graft thrombosis (14% vs. 11%) as well as 1-year rejection rates (35% vs. 31%) were not significantly different. PT in selected patients aged ≥ 50 years resulted in survival comparable with that of younger patients. In conclusion, advanced age should no longer be considered as an exclusion criterion for PT. However, good medical assessment and careful patient selection are necessary.

Challenges Associated with Pancreas and Kidney Retransplantation-A Retrospective Analysis.

Simultaneous pancreas and kidney transplantation (SPK) is an accepted treatment for diabetic patients with renal failure, and is associated with increased survival and quality of life for recipients. There are only a few publications on the outcomes of simultaneous pancreas-kidney retransplantation (Re-SPK) after previous SPK and the loss of function of both grafts. A total of 55 patients with type 1 diabetes mellitus underwent pancreas retransplantation at our center between January 1994 and March 2021. Twenty-four of these patients underwent Re-SPK after a previous SPK. All 24 operations were technically feasible. Patient survival rate after 3 months, 1 year, and 5 years was 79.2%, 75%, and 66.7%, respectively. The causes of death were septic arterial hemorrhage (n = 3), septic multiorgan failure (n = 2), and was unknown in one patient. Pancreas and kidney graft function after 3 months, 1 year, and 5 years were 70.8% and 66.7%, 66.7% and 62.5%, and 45.8% and 54.2%, respectively. Relaparotomy was performed in 13 out of 24 (54.2%) patients. The results of our study show that Re-SPK, after previously performed SPK, is a technical and immunological challenge, associated with a significantly increased mortality and complication rate; therefore, the indication for Re-SPK should be very strict. Careful preoperative diagnosis is indispensable.

Impact of Histidine-Tryptophan-Ketoglutarate Versus University of Wisconsin Solution on the Outcome of Pancreas Transplant With Cold Ischemic Time ≥12 Hours: A Retrospective Study.

OBJECTIVES: Histidine-tryptophan-ketoglutarate and University of Wisconsin solutions are currently used for pancreas graft preservation. Our hypothesis was whether the use of histidine-tryptophan-ketoglutarate solution is associated with worse pancreas graft survival than University of Wisconsin solution, in general and after prolonged cold ischemic time of ≥12 hours. MATERIALS AND METHODS: This retrospective study investigated the impact of static cold storage in histidine-tryptophan-ketoglutarate (n = 133) versus University of Wisconsin (n = 107) solution on outcomes of 240 pancreas transplant procedures. Patient and graft survival rates were compared after 1, 3, and 5 years in both groups. Serum lipase, amylase, and C-reactive protein levels and incidence of surgical complications were evaluated at postoperative week 1. A subgroup analysis of 96 grafts (52 with histidine-tryptophanketoglutarate/44 with University of Wisconsin) with pancreas graft cold ischemic time ≥12 hours was also performed. RESULTS: At mean follow-up of 75.2 ± 9.9 months, both groups demonstrated comparable short- and long-term patient survival. Overall, pancreas graft survival was slightly better in the histidine-tryptophan-ketoglutarate group (Kaplan-Meier analysis, log-rank P = .013). However, the subgroup analysis of grafts with cold ischemic time ≥12 hours showed slightly better pancreatic graft survival in the University of Wisconsin group, although not significantly (log-rank P = .95). Serum lipase and C-reactive protein levels at postoperative week 1 were higher in the histidinetryptophan-ketoglutarate group. Surgical complications were comparable. Multivariable Cox regression analysis identified neither solution as a risk factor affecting patient and graft survival. CONCLUSIONS: Although a direct comparison between histidine-tryptophan-ketoglutarate and University of Wisconsin showed better pancreas graft survival with histidine-tryptophan-ketoglutarate, the multivariable analysis showed that the perfusion solution does not significantly influence patient and graft survival. However, in the analysis of transplants with cold ischemic time ≥12 hours, pancreas graft survival was slightly better in the University of Wisconsin group, although not significantly.

Corrigendum: The Aquaporin 5 -1364A/C Promoter Polymorphism Is Associated With Cytomegalovirus Infection Risk in Kidney Transplant Recipients.

[This corrects the article DOI: 10.3389/fimmu.2019.02871.].

The NFKB1 Promoter Polymorphism (-94ins/delATTG) Is Associated with Susceptibility to Cytomegalovirus Infection after Kidney Transplantation and Should Have Implications on CMV Prophylaxis Regimens.

Infections with cytomegalovirus (CMV) are one of the most frequent opportunistic infections in kidney transplant recipients. Current risk-adapted CMV chemoprophylaxis regimens are based almost solely on the donor and recipient CMV serostatus. Of note, the NFKB1 -94ins/delATTG promoter polymorphism was recently associated with a higher risk of CMV infection. Since single genetic association studies suffer from poor reliability for drawing therapeutic implications, we performed this confirmatory study and included 256 kidney transplant recipients from 2007 to 2014 in this retrospective study. Patients were genotyped for the -94ins/delATTG NFKB1 promoter polymorphism and followed up for 12 months. The incidence of CMV infection within 12 months after kidney transplantation was 37.5% (33/88) for the ins/ins, 21.5% (28/130) for the ins/del, and 23.7% (9/38) for the del/del genotypes (p = 0.023). Moreover, we evaluated the time of CMV infection onset. Ins/ins carriers had primarily late-onset CMV infection (median 194 days; interquartile range (IQR) 117-267 days) compared with heterozygous (ins/del; median 158 days; IQR 82-195 days) and homozygous deletion allele carriers (del/del; median 95 days; 84-123 days). Multivariate-restricted Cox regression model confirmed the ins/ins genotype to be an independent risk factor for the development of late-onset CMV infections. These findings should have an impact on post-kidney transplantation CMV chemoprophylaxis regimens.

STABIL-study: The Course of Therapy, Safety and Pharmacokinetic Parameters of Conversion of Prograf® to Tacrolimus HEXAL®/Crilomus® in Renal Transplant Recipients - an Observational Study in Germany.

BACKGROUND/OBJECTIVE: Tacrolimus HEXAL®/Crilomus® is an approved generic immunosuppressant for the prevention and treatment of rejection following renal transplantation. For safe and socioeconomically efficient conversion of the innovator into a generic formulation, high- -quality data are necessary, in view of the different and country-specific comorbidities and pharmacokinetics in kidney transplant recipients. PATIENTS AND METHODS: From 2014 to 2017, we enrolled 32 kidney transplant recipients, receiving newly prescribed Tacrolimus HEXAL®/Crilomus® in 5 German centers. Efficacy and safety data were collected over 6-8 months and retrospectively compared to the period prior to conversion. RESULTS: The mean tacrolimus trough level was 4.91 ng/mL Standard Deviation (SD) (SD ±1.7) before and 5.06 ng/mL (SD ±1.97) after conversion. Mean tacrolimus trough concentration-dose-ratio (+/- SD) was 187.1 ng/mL/mg/kg/day (SD 99.2) for the reference and 205.1 ng/mL/mg/kg/day (SD 133) for the generic product, resulting in a non-significant difference of 18.0 ng/mL/mg/kg/day (SD 71.8) (p=0.84, Wilcoxon V=180). Overall, dosing had to be changed in 4 (14.8%) patients. Graft function remained stable and no rejections occurred. CONCLUSION: In conclusion, conversion to the generic tacrolimus formulation can be considered safe and feasible in long-term kidney transplant recipients in Germany. As suggested by guidelines, vigilant therapeutic drug monitoring is recommended to account for possible tacrolimus concentration variability on the individual patient level.

Biopsy findings after detection of de novo donor-specific antibodies in renal transplant recipients: a single center experience.

BACKGROUND: De novo donor-specific antibodies (DSA) are associated with an increased risk of antibody-mediated rejection and a substantial reduction of allograft survival. We hypothesized that detection of DSA should prompt a biopsy even in the absence of proteinuria and loss of estimated glomerular filtration rate (eGFR). However, data on a population without proteinuria or loss of kidney function is scant, and this is the main novelty of our study design. METHODS: Single center retrospective analysis on biopsy findings after detection of de novo DSA. One-hundred-thirty-two kidney and pancreas-kidney transplant recipients were included. Eighty-four of these patients (63.6%) underwent allograft biopsy. At the time of biopsy n = 50 (59.5%) had a protein/creatinine ratio (PCR) > 300 mg/g creatinine and/or a loss of eGFR ≥ 10 ml/min in the previous 12 months, whereas 40.5% did not. Diagnosis of rejection was performed according to Banff criteria. RESULTS: Seventy-seven (91.7%) of the biopsies had signs of rejection (47.6% antibody mediated rejection (ABMR), 13.1% cellular, 20.2% combined, 10.7% borderline). Among subjects without proteinuria or loss of eGFR ≥ 10 ml/min/a (n = 34), 29 patients (85.3%) showed signs of rejection (44.1% antibody mediated (ABMR), 14.7% cellular, 11.8% combined, 14.7% borderline). CONCLUSION: The majority of subjects with de novo DSA have histological signs of rejection, even in the absence of proteinuria and deterioration of graft function. Thus, it appears reasonable to routinely perform an allograft biopsy after the detection of de novo DSA.

Renal Function and Patient-Reported Outcomes in Stable Kidney Transplant Patients Following Conversion From Twice-Daily Immediate-Release Tacrolimus to Once-Daily Prolonged-Release Tacrolimus: A 12-Month Observational Study in Routine Clinical Practice in Germany (ADAGIO).

INTRODUCTION: This 12-month, noninterventional study on routine clinical practice in Germany evaluated renal function in stable kidney transplant recipients converted from immediate-release tacrolimus (IR-T) to prolonged-release tacrolimus (PR-T). METHODS: Renal function was assessed in 183 patients by estimated glomerular filtration rate using the modification of diet in renal disease-4 formula. Self-reported gastrointestinal health-related quality of life, adherence, satisfaction with PR-T, suspected rejection episodes, and safety were also assessed at conversion and at 3, 6, and 12 months. RESULTS: Conversion from IR-T to PR-T resulted in stable kidney function over 12 months, with a difference in estimated glomerular filtration rate between the first and final visits of 0.1 mL/min/1.73 m2 (95% confidence interval, -1.6, 1.8). Eight patients experienced an acute rejection episode (4.4%). At each assessment, gastrointestinal health-related quality of life was low and adherence was high. Most patients reported that they were very satisfied (69.8%) or satisfied (28.1%) with PR-T at the final visit. Among patients reporting a preference, 78.4% preferred PR-T, 2.2% preferred IR-T, and 19.4% reported no preference. The safety profile of PR-T was consistent with that previously described. CONCLUSION: Conversion of stable kidney transplant recipients from IR-T to PR-T provided stable kidney and graft function over 12 months (Verband Forschender Arzneimittelhersteller--registered study: NIS ADV-02).

Detection of pre-existing SARS-CoV-2-reactive T cells in unexposed renal transplant patients.

BACKGROUND: Recent data demonstrate potentially protective pre-existing T cells reactive against the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in samples of healthy blood donors, collected before the SARS-CoV-2 pandemic. Whether pre-existing immunity is also detectable in immunosuppressed patients is currently not known. METHODS: Fifty-seven patients were included in this case-control study. We compared the frequency of SARS-CoV-2-reactive T cells in the samples of 20 renal transplant (RTx) patients to 20 age/gender matched non-immunosuppressed/immune competent healthy individuals collected before the onset of the SARS-CoV-2 pandemic. Seventeen coronavirus disease 2019 (COVID-19) patients were used as positive controls. T cell reactivity against Spike-, Nucleocapsid-, and Membrane- SARS-CoV-2 proteins were analyzed by multi-parameter flow cytometry. Antibodies were analyzed by neutralization assay. RESULTS: Pre-existing SARS-CoV-2-reactive T cells were detected in the majority of unexposed patients and healthy individuals. In RTx patients, 13/20 showed CD4+ T cells reactive against at least one SARS-CoV-2 protein. CD8+ T cells reactive against at least one SARS-CoV-2 protein were demonstrated in 12/20 of RTx patients. The frequency and Th1 cytokine expression pattern of pre-formed SARS-CoV-2 reactive T cells did not differ between RTx and non-immunosuppressed healthy individuals. CONCLUSIONS: This study shows that the magnitude and functionality of pre-existing SARS-CoV-2 reactive T cell in transplant patients is non-inferior compared to the immune competent cohort. Although several pro-inflammatory cytokines were produced by the detected T cells, further studies are required to prove their antiviral protection.