Chronic Active Antibody-Mediated Rejection Following COVID-19 Infection in a Kidney Transplant Recipient: A Case Report

Impact of COVID-19 pandemic on transplant laboratories: How to mitigate?

A positive flow cytometry crossmatch (FCXM) due to donor specific antibodies (DSA) constitutes a risk for kidney transplantation; such a finding may indicates an unacceptable donor for this patient. However, positive FCXM in the absence of DSA is considered discordant and need further investigations. During COVID-19 pandemic, we observed 22% discordant results out of 445 FCXM performed during eight months period in our laboratory and another 7% were invalid due to high background negative control (NC). No study has addressed the impact of COVID-19 pandemic on FCXM and the overall pre-kidney transplant workups or described a solution to deal with these non-specific reactivities. Herein, we analyzed all FCXM results in SARS-CoV-2 seropositive patients and addressed how this pandemic affected significantly the pre-kidney transplant workups, highlighting both technical and financial implications. We also shared our modified FCXM procedures using dithiotheritol (DTT) sera treatment or blocking donor cells with negative control human serum (NCS) which we found to be successful to abrogate 98% of all discordant FCXM results and to validate all invalid results due to high background NC. In conclusion, COVID-19 pandemic has affected our HLA laboratory significantly by creating many false positive or invalid crossmatch results. Transplant laboratories must consider this before test interpretations and immune risk assessments. We recommend the use of DTT serum treatment to remove nonspecific bindings in the sera of kidney transplant candidates and the use of NCS-blocked donor cells to correct high background when performing FCXM in transplant candidates or donors with recent history of SARS-CoV-2 immunization respectively.

Low incidence of de novo HLA antibodies after COVID-19 vaccination: A cohort study of patients awaiting kidney transplantation

BACKGROUND

Antibodies against human leukocyte antigen (anti-HLA Abs) are associated with an increased risk of allograft loss. Herein, we report the prospective follow-up for anti-HLA Abs formation in 103 patients with end-stage kidney disease on the waiting list for transplantation who underwent COVID-19 vaccination.

PATIENTS AND METHODS

Sera were tested before and after vaccination using Luminex technology. The cohort comprised of 62 males and 41 females with a mean age of 56 ± 14 years. The patients received BNT162b2 (80.4%), mRNA-1273 (18.5%), AZD1222 (0.40%), or ChAdOx1-S (0.80%) vaccine. Patients were tested before and within 119 ± 50, 95 ± 46 and 25 ± 26 days after the first, second, and third dose of the vaccine, respectively.

RESULTS

No significant change in calculated panel reactive antibody (cPRA) after vaccination was seen. Although 98.1% of patients had no change in anti-HLA Abs profile or cPRA after vaccination, two patients (1.9%) developed de novo anti-HLA Abs against class I or II HLA antigens. In those two patients, the cPRA changed from 0% and 63% at baseline to 9% and 90% after vaccination, respectively. Both patients received the BNT162b2 mRNA-based vaccine. The earliest detected anti-HLA Abs was 18 days after the first dose.

CONCLUSION

In rare cases, new anti-HLA antibodies were observed after COVID-19 vaccination, with potential implications for transplantation. The low incidence of this phenomenon is outweighed by the clinical benefits of vaccination.

Kidney Allograft Rejection and Coronavirus Disease 2019 Infection: A Narrative Review

The world has experienced a global medical and socioeconomic burden following the coronavirus disease 2019 (COVID-19) pandemic. COVID-19 is a systemic disease and may affect different organs including the kidneys. Current literature contains reports on COVID-19-related conditions such as acute kidney injury, and complications experienced by chronic kidney disease, end stage kidney disease, and kidney transplant patients. Here, we discuss the incidence of kidney allograft rejection, immunosuppression management and rejection risk, donor-specific antibodies and previous rejection episodes, and rejection outcomes in kidney transplant recipients with COVID-19 by reviewing current studies.

Exacerbation of Intimal Fibrosis and Endarteritis in a Kidney Transplant Recipient with Chronic Active Antibody-Mediated Rejection and COVID-19: A Case Report

Kidney transplant recipients are immunocompromised hosts at risk for comorbidity and mortality due to infection. Currently, there are no established guidelines for the management of immunosuppressed transplant recipients with coronavirus disease 2019 (COVID-19). The impact of COVID-19 and its therapeutic management on chronic active antibody-mediated rejection (CAAMR) are still unclear. Here, we report a case of CAAMR exacerbation with endarteritis and intimal fibrosis after COVID-19. A 41-year-old female kidney transplant recipient with CAAMR was admitted to a local hospital with moderately severe COVID-19. Her doses of tacrolimus and mycophenolate mofetil were reduced, and she was administered methylprednisolone pulse and antiviral drugs. This resulted in a good clinical course and she was discharged in 15 days. During and after hospitalization, the immunosuppressants were gradually returned to the baseline levels. However, about 1.5 months after discharge, the serum creatinine level became elevated. An indication kidney biopsy showed CAAMR with intimal fibrosis and endarteritis in all interlobular arteries. An increase of immunosuppressant led to a decrease of the serum creatinine level. Factors contributing to CAAMR with intimal fibrosis and endarteritis may include (1) insufficient immunosuppression due to changes in the levels of immunosuppressive; (2) overlap with endothelial cell injury caused by COVID-19, and (3) an immune-activated state associated with COVID-19. COVID-19 is a life-threatening disease that can result in unexpected changes in immunological status. Possible allograft rejection should be carefully managed in such patients.

Infection, Rejection, and the Connection

Solid organ transplantation is a life-saving treatment for people with end-stage organ disease. Immune-mediated transplant rejection is a common complication that decreases allograft survival. Although immunosuppression is required to prevent rejection, it also increases the risk of infection. Some infections, such as cytomegalovirus and BK virus, can promote inflammatory gene expression that can further tip the balance toward rejection. BK virus and other infections can induce damage that resembles the clinical pathology of rejection, and this complicates accurate diagnosis. Moreover, T cells specific for viral infection can lead to rejection through heterologous immunity to donor antigen directly mediated by antiviral cells. Thus, viral infections and allograft rejection interact in multiple ways that are important to maintain immunologic homeostasis in solid organ transplant recipients. Better insight into this dynamic interplay will help promote long-term transplant survival.

Accelerated Cardiac Allograft Vasculopathy in an Orthotopic Heart Transplant Recipient with Prior COVID-19

BACKGROUND Cardiac allograft vasculopathy (CAV) is a post-orthotopic heart transplant (OHT) complication driven by intimal smooth muscle proliferation and immune hyperactivity to donor heart tissue. Accelerated CAV leads to allograft failure within 1 year after receiving a normal angiogram result. Viruses can contribute to CAV development, but CAV after SARS-CoV-2 infection has not been reported to date. CASE REPORT A 48-year-old man, 5 years after OHT for non-ischemic cardiomyopathy, was admitted to the Cardiac Care Unit with 3 days of abdominal pain, dyspnea, and palpitations. His medical history included hyperlipidemia and insulin-dependent diabetes. He was compliant with all medications. Two months prior, he had a mild COVID-19 case. An echocardiogram and coronary angiogram 6 and 9 months prior, respectively, were unremarkable. Right and left heart catheterization demonstrated increased filling pressures, a cardiac index of 1.7 L/ml/m², and diffuse vasculopathy most severe in the LAD artery. Flow could not be restored despite repeated ballooning and intra-catheter adenosine. Empiric ionotropic support, daily high-dose methylprednisolone, and plasmapheresis were started. A few days later, the patient had cardiac arrest requiring venoarterial extracorporeal membranous oxygenation. Given CAV's irreversibility, re-transplantation was considered, but the patient had an episode of large-volume hemoptysis and remained clinically unstable for transplant. The patient died while on palliative care. CONCLUSIONS Our patient developed accelerated CAV 2 months after having COVID-19. While CAV has known associations with certain viruses, its incidence after SARS-CoV-2 infection is unknown. Further research is needed to determine if prior SARS-CoV-2 infection is a risk factor for development of CAV in OHT recipients.

HLA Sensitization in the Era of COVID-19: Single-Center Experience

It is well known that several viral infections are capable of triggering the formation of HLA antibodies; however, an association between SARS-CoV-2 and the development of anti-HLA antibodies is not yet confirmed. In this study, we compared the prevalence of HLA antibody before and after COVID-19 infection in a cohort of 3 groups included 58 healthy nonsensitized employees (HNEs), 130 kidney transplant recipients (KTRs), and 62 kidney transplant candidates. There were no significant changes observed in HLA class I antibodies in any of the groups, but evaluation of antibodies to HLA class II revealed a significant change in the KTR group (P = .0184) after acquiring COVID-19 infection and in the HNE group (P = .0043) when compared to the reported prevalence in a similar population. Although we observed the emergence of convalescent de novo donor-specific antibodies in 2 patients, we did not encounter any rejection episodes in the KTR group. Finally, the results of flow cytometry crossmatch in the HNE group were not consistent with the state of antibodies. In conclusion, COVID-19 infection has the potential to produce class II antibodies but with little effect on preexisting sensitization. These antibodies are likely to be transient and not necessarily causing positive crossmatch with the corresponding antigens at the proper mean fluorescent intensity and therefore should not affect access to transplantation. There is a need for further evaluation to ascertain the genuineness of these antibodies and their exact effect on transplant readiness and outcomes.

COVID-19 and Kidney Transplantation: Epidemiology, Histopathological Presentation, Clinical Presentation and Outcomes, and Therapeutic Strategies

Multiple case series of kidney transplant recipients with COVID-19 have shown increased mortality compared to nontransplant patients. To date, we do not have high-level evidence to inform immunosuppression minimization strategies in infected transplant recipients. Most centers, however, have adopted an early antimetabolite withdrawal in addition to other interventions. The epidemiological problem concerns also dialysis patients and waitlisted patients who have a higher COVID-19 infection diffusion with respect to kidney transplant recipients. Several factors influence mortality among kidney transplant recipients. Among these factors are the age, race, and comorbidity factors, such as hypertension, diabetes mellitus, obesity, and previous respiratory problems. Treatment is still limited. The only effective antiviral drug is remdesivir that should be administered before the development of the cytokine storm. Vaccination seems to be useful, but due to the concomitant immunosuppression limiting its efficacy, at least three or four doses should be administered.

Successful ABO-incompatible living donor kidney transplantation in a recipient who developed flow cytometry crossmatch-positive donor-specific class I HLA antibodies following COVID-19 vaccination

The effects of COVID-19 vaccination on alloimmunization and clinical impact in transplant candidates remain largely unknown. In a 61-year-old man who had no donor-specific antibodies (DSA) and was planned to undergo ABO-incompatible kidney transplantation (ABOi KT), DSAs (anti-A24, anti-B51, anti-Cw14) developed after COVID-19 vaccination. After desensitization therapy, antibody level was further increased, leading to flow cytometric crossmatch-positive status. Donor-specific T cell immunity using interferon-gamma ELISPOT was continuously negative, whereas SARS-CoV-2 specific T cell immunity was intact. After confirming the C1q-negative status of DSA, the patient received ABOi KT. The patient had stable graft function and suppressed alloimmunity up to two months after KT. COVID-19 vaccination might relate to alloimmunization in transplant candidates, and desensitization through immune monitoring can help guide transplantation. This article is protected by copyright. All rights reserved.

Coronavirus-19 infection in kidney transplant recipients: A comprehensive review

The COVID-19 pandemic has disrupted health care across the globe. Since the beginning of the pandemic, there have been substantial changes in the approach toward kidney transplantation and management of the virus in transplant recipients. Chronic immunosuppression and comorbidities in renal transplant recipients place them at risk during the pandemic. Data on the risk factors, presentation, and management of kidney transplant patients have become more robust over time. Relevant data on this topic was procured and synthesized with the aid of a comprehensive Medline search on all published studies that investigated COVID-19 infection in kidney transplant recipients. This comprehensive review summarizes the current literature on the epidemiology, clinical features, complications, graft outcomes, and current management of COVID-19 infection in kidney transplant recipients. We further summarize published literature on immunization in kidney transplant recipients.

Native and transplant kidney histopathological manifestations in association with COVID-19 infection: A systematic review

BACKGROUND

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can result in clinically significant multi-system disease including involvement in the kidney. The underlying histopathological processes were unknown at the start of the pandemic. As case reports and series have been published describing the underlying renal histopathology from kidney biopsies, we have started to gain an insight into the renal manifestations of this novel disease.

AIM

To provide an overview of the current literature on the renal histopathological features and mechanistic insights described in association with coronavirus disease 2019 (COVID-19) infection.

METHODS

A systematic review was performed by conducting a literature search in the following websites-‘PubMed’, ‘Web of Science’, ‘Embase’ and ‘Medline-ProQuest’ with the following search terms-“COVID-19 AND kidney biopsy”, “COVID-19 AND renal biopsy”, “SARS-CoV-2 AND kidney biopsy” and “SARS-CoV-2 AND renal biopsy”. We have included published data up until February 15, 2021, which includes kidney biopsies (native, transplant and postmortem) from patients with COVID-19. Data on clinical presentation, histopathological features, management and outcome was extracted from the reported studies.

RESULTS

The total number of biopsies reported on here is 288, of which 189 are postmortem, 84 native and 15 transplants. The results are varied and show underlying pathologies ranging from collapsing glomerulopathy and acute tubular injury (ATI) to anti-nuclear cytoplasmic antibody associated vasculitis and pigment nephropathy. There was variation in the specific treatment used for the various renal conditions, which included steroids, hydroxychloroquine, eculizumab, convalescent plasma, rituximab, anakinra, cyclophosphamide and renal replacement therapy, amongst others. The pathological process which occurs in the kidney following COVID-19 infection and leads to the described biopsy findings has been hypothesized in some conditions but not others (for example, sepsis related hypoperfusion for ATI). It is important to note that this represents a very small minority of the total number of cases of COVID-19 related kidney disease, and as such there may be inherent selection bias in the results described. Further work will be required to determine the pathogenetic link, if any, between COVID-19 and the other renal pathologies.

CONCLUSION

This report has clinical relevance as certain renal pathologies have specific management, with the implication that kidney biopsy in the setting of renal disease and COVID-19 should be an early consideration, dependent upon the clinical presentation.

SARS Cov-2 vaccination induces de novo donor-specific HLA antibodies in a renal transplant patient on waiting list: A case report

The ability of COVID‐19 vaccination to induce anti‐HLA antibodies (Abs) formation in renal transplant candidates is not well studied. A 42‐year‐old man on a renal transplant waitlist, with no sensitization history, was tested for DSA before and after COVID‐19 vaccination. Patient has consistently tested negative for COVID‐19 virus. Eighteen days after receiving first dose of mRNA‐based vaccine, flow cytometry crossmatch (FCXM) was strongly positive with de novo donor‐specific Ab (dnDSA) against B57 and de novo non‐DSA against B58. Before vaccination, preliminary FCXM was negative with no anti‐HLA Abs. This event prompted the transplant team to cancel the surgery. COVID‐19 vaccination could be associated with anti‐HLA Abs formation in renal patients on waitlists that could affect future transplantability.

Therapies for Chronic Allograft Rejection

Remarkable advances have been made in the pathophysiology, diagnosis, and treatment of antibody-mediated rejection (ABMR) over the past decades, leading to improved graft outcomes. However, long-term failure is still high and effective treatment for chronic ABMR, an important cause of graft failure, has not yet been identified. Chronic ABMR has a relatively different phenotype from active ABMR and is a slowly progressive disease in which graft injury is mainly caused by de novo donor specific antibodies (DSA). Since most trials of current immunosuppressive therapies for rejection have focused on active ABMR, treatment strategies based on those data might be less effective in chronic ABMR. A better understanding of chronic ABMR may serve as a bridge in establishing treatment strategies to improve graft outcomes. In this in-depth review, we focus on the pathophysiology and characteristics of chronic ABMR along with the newly revised Banff criteria in 2017. In addition, in terms of chronic ABMR, we identify the reasons for the resistance of current immunosuppressive therapies and look at ongoing research that could play a role in setting better treatment strategies in the future. Finally, we review non-invasive biomarkers as tools to monitor for rejection.