Outcome of 313 Czech Patients With IgA Nephropathy After Renal Transplantation

Risk factors and outcomes of IgA nephropathy recurrence after kidney transplantation: a systematic review and meta-analysis

Background

IgA nephropathy may recur in patients receiving kidney transplantation due to IgA nephropathy induced renal failure. The risk factors for recurrence are still at issue. The aim of this study was to conduct a systematic review and meta-analysis to assess risk factors and outcomes for IgA nephropathy recurrence.

Methods

We used PubMed, EMBASE, Cochrane Library, Web of Science, Scopus, CNKI, WanFang, VIP and CBM to search for relevant studies published in English and Chinese. Cohort or case-control studies reporting risk factors or outcomes for IgA nephropathy recurrence were included.

Results

Fifty-eight studies were included. Compare to no recurrence group, those with IgAN recurrence had younger age (mean difference [MD]=-4.27 years; risk ratio [RR]=0.96), younger donor age (MD=-2.19 years), shorter time from IgA nephropathy diagnosis to end stage renal disease (MD=-1.84 years; RR=0.94), shorter time on dialysis (MD=-3.14 months), lower human leukocyte-antigen (HLA) mismatches (MD=-0.11) and HLA-DR mismatches (MD=-0.13). HLA-B46 antigen (RR=0.39), anti-IL-2-R antibodies induction (RR=0.68), mycophenolate mofetil (RR=0.69), and pretransplant tonsillectomy (RR=0.43) were associated with less IgAN recurrence. Of note, male recipient gender (RR=1.17), related donor (RR=1.53), retransplantation (RR=1.43), hemodialysis (RR=1.68), no induction therapy (RR=1.73), mTOR inhibitor (RR=1.51), angiotensin-converting enzyme inhibitors or angiotensin-receptor blockers (RR=1.63) were risk factors for IgAN recurrence. Recurrence increased the risk of graft loss (RR=2.19).

Conclusions

This study summarized the risk factors for recurrence of IgA nephropathy after kidney transplantation. Well-designed prospective studies are warranted for validation.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=377480, identifier CRD42022377480.

Evaluation of the Modified Oxford Score in Recurrent IgA Nephropathy in North American Kidney Transplant Recipients: The Banff Recurrent Glomerulonephritis Working Group Report

BACKGROUND

The modified Oxford classification mesangial and endocapillary hypercellularity, segmental sclerosis, interstitial fibrosis/tubular atrophy, and the presence of crescents (MEST-C) of immunoglobulin A nephropathy (IgAN) was recently shown to be a predictor of graft failure in Asians with recurrent IgAN. We aimed to validate these findings in a cohort from North American centers participating in the Banff Recurrent Glomerulopathies Working Group.

METHODS

We examined 171 transplant recipients with end-stage kidney disease because of IgAN; 100 of them with biopsy-proven recurrent IgAN (57 of them had complete MEST-C scores) and 71 with no recurrence.

RESULTS

IgAN recurrence, which was associated with younger age at transplantation ( P  = 0.012), strongly increased the risk of death-censored graft failure (adjusted hazard ratio, 5.10 [95% confidence interval (CI), 2.26-11.51]; P  < 0.001). Higher MEST-C score sum was associated with death-censored graft failure (adjusted hazard ratio, 8.57 [95% CI, 1.23-59.85; P  = 0.03] and 61.32 [95% CI, 4.82-779.89; P  = 0.002] for score sums 2-3 and 4-5 versus 0, respectively), and so were the single components endocapillary hypercellularity, interstitial fibrosis/tubular atrophy, and crescents ( P  < 0.05 each). Overall, most of the pooled adjusted hazard ratio estimates associated with each MEST-C component were consistent with those from the Asian cohort (heterogeneity I2 close to 0%, and P  > 0.05).

CONCLUSIONS

Our findings may validate the prognostic usefulness of the Oxford classification for recurrent IgAN and support the inclusion of the MEST-C score in allograft biopsies diagnostic reports.

Emerging role of monoclonal antibodies in the treatment of IgA nephropathy

INTRODUCTION

IgA nephropathy is the most common primary glomerulonephritis worldwide. Immune complexes, composed of galactose-deficient IgA1 and Gd-IgA1 autoantibodies, are deposited in the mesangial area of the glomeruli where they induce complement-mediated inflammation. This may result in the reduced kidney function which can progress to end stage kidney disease.Treatment options are very limited. Treatments which directly affect the formation of pathogenic Gd-IgA1 antibodies and anti-Gd-IgA1 antibody-containing immune complexes are needed.

AREAS COVERED

This article reviews potential therapies, namely monoclonal antibodies, that may affect the main axis of pathogenesis of IgA nephropathy with discussion of their potential impact on the outcome of IgAN. PubMed was used to perform the literature search which included papers on "treatment of IgA nephropathy"combined with "biological therapy", or "monoclonal antibodies, atacicept, sibeprenlimab, rituximab, felzartamab, narsoplimab, iptacopan" published up until 2023.

EXPERT OPINION

New treatment options are aimed at the immunopathogenesis of IgAN including depletion or modulation of Gd-IgA1 producing B cells, plasma cells, alternate or lectin pathway of complement. Monoclonal antibodies may target both B cells and T cells and also the factor needed for their activation and survival, e.g BAFF or APRIL.

Cytokines and Production of Aberrantly O-Glycosylated IgA1, the Main Autoantigen in IgA Nephropathy

Immunoglobulin A (IgA) nephropathy is the most common primary glomerulonephritis worldwide, with no disease-specific treatment and up to 40% of patients progressing to kidney failure. IgA nephropathy (IgAN), characterized by IgA1-containing immunodeposits in the glomeruli, is considered to be an autoimmune disease in which the kidneys are injured as innocent bystanders. Glomerular immunodeposits are thought to originate from the circulating immune complexes that contain aberrantly O-glycosylated IgA1, the main autoantigen in IgAN, bound by IgG autoantibodies. A common clinical manifestation associated with IgAN includes synpharyngitic hematuria at disease onset or during disease activity. This observation suggests a connection of disease pathogenesis with an activated mucosal immune system of the upper-respiratory and/or gastrointestinal tract and IgA1 glycosylation. In fact, some cytokines can enhance production of aberrantly O-glycosylated IgA1. This process involves abnormal cytokine signaling in IgA1-producing cells from patients with IgAN. In this article, we present our view of pathogenesis of IgAN and review how some cytokines can contribute to the disease process by enhancing production of aberrantly glycosylated IgA1. We also review current clinical trials of IgAN based on cytokine-targeting therapeutic approaches.

New Treatment Strategies for IgA Nephropathy: Targeting Plasma Cells as the Main Source of Pathogenic Antibodies

Immunoglobulin A nephropathy (IgAN) is a rare autoimmune disorder and the leading cause of biopsy-reported glomerulonephritis (GN) worldwide. Disease progression is driven by the formation and deposition of immune complexes composed of galactose-deficient IgA1 (Gd-IgA1) and Gd-IgA1 autoantibodies (anti-Gd-IgA1 antibodies) in the glomeruli, where they trigger complement-mediated inflammation that can result in loss of kidney function and end-stage kidney disease (ESKD). With the risk of progression and limited treatment options, there is an unmet need for therapies that address the formation of pathogenic Gd-IgA1 antibody and anti-Gd-IgA1 antibody-containing immune complexes. New therapeutic approaches target immunological aspects of IgAN, including complement-mediated inflammation and pathogenic antibody production by inhibiting activation or promoting depletion of B cells and CD38-positive plasma cells. This article will review therapies, both approved and in development, that support the depletion of Gd-IgA1-producing cells in IgAN and have the potential to modify the course of this disease. Ultimately, we propose here a novel therapeutic approach by depleting CD38-positive plasma cells, as the source of the autoimmunity, to treat patients with IgAN.

Kidney transplantation in pediatric patients with rheumatologic disorders

PURPOSE OF REVIEW

Providers caring for children with end-stage kidney disease from rheumatologic conditions face questions such as when to proceed with kidney transplantation, how common is disease recurrence posttransplant, how does recurrent disease impact patient and allograft outcomes, and what approaches are available to prevent and treat recurrent disease. We discuss recent developments and relevant literature that address these questions for the most common rheumatologic disorders that lead to end-stage kidney disease in childhood namely, systemic lupus erythematosus, IgA nephropathy, IgA Vasculitis/Henoch Schoenlein Purpura, and Anti-Neutrophil Cytoplasmic Antibody (ANCA)-associated vasculitis.

RECENT FINDINGS

Recent data suggest that children with IgA nephropathy, IgA vasculitis, and ANCA-associated vasculitis have similar patient and allograft survival to other conditions despite the risk of recurrent disease, yet those with lupus have worse posttransplant patient and allograft outcomes. A period of disease quiescence may be prudent prior to transplantation to decrease the risk of recurrence, which is associated with decreased allograft survival. Data on preventive strategies and treatment options are limited.

SUMMARY

It is recommended that patients with systemic rheumatologic conditions not be excluded from kidney transplantation but that patients be counseled on the risk of potential recurrent disease with its impact on transplant outcomes.