Single cohort study: ABO-incompatible kidney transplant recipients have a higher risk of lymphocele formation

Outcomes of ABO-incompatible kidney transplants with very high isoagglutinin titers: a single-center experience and literature review

Background

ABO-incompatible kidney transplantation (ABOi-KTx) represents a possible solution to address the shortage of kidney donors. However, these transplants present immunological challenges, particularly when isoagglutinin titers are elevated pretransplant.

Methods

Single-center retrospective study describing clinical and biological outcomes of 8 patients who underwent ABOi-KTx with initial isoagglutinin titers ≥ 1/512. All patients followed a desensitization protocol combining immunosuppression (rituximab, tacrolimus, mycophenolate mofetil, steroids), and specific or semi-specific apheresis sessions. Clinical and biological data were extracted from electronic medical records.

Results

There were 5 males; median age of 62 years [34-82 years]; all achieved an isoagglutinin titer of ≤1/8 before transplantation after a median of 13 (range: 9-15) apheresis sessions. Three patients (37%) experienced acute humoral rejection, which required additional plasmapheresis sessions. Two patients developed chronic active rejection, successfully treated. On the infectious side, three patients developed BK-virus reactivation. Two patients developed cytomegalovirus viremia, and two others presented with bacterial infections. Surgically, two patients developed a lymphocele, and one had a perirenal hematoma. All patients survived the transplant with stable renal function: mean serum creatinine was 138 ± 15 µmol/L after four years of follow-up.

Conclusion

ABO-incompatible kidney transplantation, even in patients with high isoagglutinin titers, is feasible and can achieve favorable long-term graft and patient survival outcomes. However, these procedures require substantial clinical expertise and close follow-up to monitor and manage the elevated risks of infection and rejection in this population.

Non-antigen-specific Immunoadsorption Is a Risk Factor for Severe Postoperative Infections in ABO-Incompatible Kidney Transplant Recipients

ABO-incompatible (ABOi) living kidney transplantation (KTx) is an established procedure to address the demand for kidney transplants with outcomes comparable to ABO-compatible KTx. Desensitization involves the use of immunoadsorption (IA) to eliminate preformed antibodies against the allograft. This monocentric retrospective study compares single-use antigen-selective Glycosorb® ABO columns to reusable non-antigen-specific Immunosorba® immunoglobulin adsorption columns regarding postoperative infectious complications and outcome. It includes all 138 ABOi KTx performed at Freiburg Transplant Center from 2004-2020. We compare 81 patients desensitized using antigen-specific columns (sIA) to 57 patients who received IA using non-antigen-specific columns (nsIA). We describe distribution of infections, mortality and allograft survival in both groups and use Cox proportional hazards regression to test for the association of IA type with severe infections. Desensitization with nsIA tripled the risk of severe postoperative infections (adjusted HR 3.08, 95% CI: 1.3-8.1) compared to sIA. nsIA was associated with significantly more recurring (21.4% vs. 6.2%) and severe infections (28.6% vs. 8.6%), mostly in the form of urosepsis. A significantly higher proportion of patients with sIA suffered from allograft rejection (29.6% vs. 14.0%). However, allograft survival was comparable. nsIA is associated with a two-fold risk of developing a severe postoperative infection after ABOi KTx.

Postoperative Events in Incompatible Living Donor Kidney Transplant Recipients Undergoing Prior Desensitization

BACKGROUND

Living donor kidney transplantation (LDKT) is one of the best options for patients with chronic renal failure, but approximately one-third of cases are limited by incompatibility ABO and/or HLA between recipient and donor. This study aims to analyze the surgical complications and bleeding events presented in ABO-incompatible (ABOi) and HLA-incompatible (HLAi) patients within a pre-transplant desensitization program compared with ABO-compatible (ABOc) recipients.

MATERIAL AND METHODS

We performed a retrospective analysis of ABOi and HLAi recipients undergoing LKDT between 2009 and 2019, resulting in a total of 62 patients that we compared with the same number of ABOc performed consecutively before 2019. The following variables were analyzed: surgical complications, presence, size and rate of reintervention of peri-graft hematomas, and number of transfusions received in the postoperative period.

RESULTS

No statistical differences were shown in donor and recipient age, BMI, or sex; in the case of pre-surgical hematocrit, the ABOi group presented slightly lower figures. In the incompatible group (ABOi + HLAi), we found a greater number of postoperative surgical complications when analyzing the number of hematomas, size, need for surgical reintervention, and the number of blood units transfused; incompatible patients showed higher rates of hematomas, need for surgical reinterventions, and transfused units (P < .05).

CONCLUSION

Desensitized patients need more transfusions, have a greater number and size of hematomas, and have higher reintervention rates. Although these are present in greater numbers, we did not observe statistically significant differences in the number of surgical complications.

Experiences and Short-Term Outcomes of Kidney Transplantation During the Coronavirus Disease 2019 Pandemic From a Medium-Volume Transplantation and Superregional Coronavirus Disease 2019 Treatment Center

Introduction

The coronavirus, which first appeared in 2019, developed into a pandemic during 2020. It remains unclear to what extent the pandemic endangers the safety of kidney transplantation programs. In this study, we evaluated the short-term outcomes of our patients receiving a kidney transplant during the first phase and compared them with patients who received a kidney transplant immediately before the coronavirus pandemic.

Materials and Methods

Our retrospective study includes 34 kidney transplant recipients between October 1, 2019, and April 30, 2020. Nineteen patients from the phase immediately prior to the first coronavirus wave (pre-corona group), and 15 patients from the phase of the first coronavirus wave (corona group) were studied. We retrospectively evaluated demographic data, postoperative short-term outcomes and complications, immunosuppression regime, coronavirus infection status, and behavior during the first phase of the pandemic.

Results

There were no differences between the 2 groups regarding short-term outcomes and postoperative complications or in immunosuppressive medication. After the introduction of intensified hygienic conditions and routine swabs prior to transplantation, no nosocomial SARS-CoV-2 infections occurred. In the outpatient setting, none of the patients developed a SARS-CoV-2 infection. The majority of patients performed voluntary quarantine.

Conclusions

The short-term outcomes after kidney transplantation during the first phase of the coronavirus pandemic were comparable to pre-pandemic patients, and no SARS-CoV-2-associated death or transplant failure occurred in our small cohort. We considered patient compliance with hygiene and self-isolation measures very high. Nevertheless, in further phases of the pandemic, the continuation of the living kidney donation program must be critically evaluated.

Long-term Follow-up of ABO-Incompatible Kidney Transplantation in Freiburg, Germany: A Single-Center Outcome Report

BACKGROUND

ABO-incompatible kidney transplantation (ABOi-KT) is an established way to enlarge the donor pool around the world. Comparability of long-term success and complications to ABO-compatible kidney transplantation (ABOc-KT) are still under debate.

METHODS

We evaluated all patients with a living donor kidney transplantation performed between April 1, 2004, and March 31, 2019.

RESULTS

A total of 137 ABOi-KT and 346 ABOc-KT were analyzed. We excluded 4 ABOi-KT recipients and 178 ABOc-KT recipients with cyclosporine A-based immunosuppression or without basiliximab induction. Three patients of the ABOi-KT cohort and 6 patients of the ABOc-KT cohort were lost to follow-up and therefore excluded. The patient characteristics were comparable except for the higher age of transplant recipients in the ABOc-KT cohort and longer follow-up of the ABOi-KT cohort. The mean estimated 15-year recipient survival was 89% in the ABOi-KT cohort and 91% in the ABOc-KT cohort (P = .39). Mean estimated graft survival was 71% in the ABOi-KT cohort and 87% in the ABOc-KT cohort (P = .68). The estimated glomerular filtration rate (Modification of Diet in Renal Disease) measured in the last follow-up was 51 mL/min/1.73 m² in the ABOi-KT cohort and 50 mL/min/1.73 m² in the ABOc-KT cohort (P = .36). The incidence for antibody-mediated rejection, T cell-mediated rejections, and infectious complications requiring hospitalization was not different between the cohorts. In the ABOi-KT cohort, we found significantly more lymphoceles and consequent surgical revision procedures.

CONCLUSIONS

At our center, ABOi-KT has as good long-term results as ABOc-KT in terms of patient survival, graft survival, and complications, with the exception of increased lymphocele formation.

ABO-incompatible living kidney transplantation

ABO-incompatible living kidney transplantation is nowadays a routine procedure to expand living donor pool. The past decades have seen the evolution of desensitization protocol and immunosuppression regimen. Despite increased bleeding events, infectious complications, and rejection episodes reported in some studies, favorable graft and patient survival rate are now achieved, regardless of various protocols among transplant centers. Several issues such as the usage of rituximab and standardization of blood group antibody titration remain to be settled. The deposition of C4d is no longer the histopathologic hallmark of antibody-mediated rejection, which have inspired innovative strategies of peripheral molecular screening and the improvement of histological diagnosis of AMR (antibody-mediated rejection). The better understanding of the underlying mechanism might facilitate the distinction and therapeutic schemes of AMR.