Pre-transplant course and risk of kidney transplant failure in IgA nephropathy patients

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.

IgA Nephropathy: An Interesting Autoimmune Kidney Disease

Immunoglobulin A nephropathy (IgAN) is the most common primary glomerulonephritis worldwide. It is a leading cause of chronic kidney disease and progresses to end-stage kidney disease in up to 40% of patients about 20 years after diagnosis. Additionally, IgAN is associated with significant mortality. The diagnosis currently necessitates a kidney biopsy, as no biomarker sufficiently specific and sensitive is available to supplant the procedure. Patients display significant heterogeneity in the epidemiology, clinical manifestations, renal progression, and long-term outcomes across diverse racial and ethnic populations. Recent advances in understanding the underlying pathophysiology of the disease have led to the proposal of a four-hit hypothesis supporting an autoimmune process. To date, there is no disease-specific treatment but, with a better understanding of the disease pathogenesis, new therapeutic approaches are currently being tested in clinical trials. In this review, we examine the multiple facets and most recent advances of this interesting disease.

Justicidin B Inhibits PDGF-BB-Induced Proliferation and ECM Accumulation in Mesangial Cells via Nrf2/HO-1 and Akt/mTOR Signaling Pathway

Mesangial proliferative glomerulonephritis (MsPGN) is characterized by mesangial cell proliferation, inflammation, and extracellular matrix deposition in the mesangial area, which develops into glomerulosclerosis and contributes to end-stage renal disease. Justicidin B is a bioactive compound isolated from Justicia procumbens L., a traditional herbal remedy that reduces proteinuria in nephritis. However, the mechanism of Justicidin B’s therapeutic effect on MsPGN remains unclear. This study was aimed to explore the positive effect of Justicidin B on MsPGN. The results showed that Justicidin B attenuated the proliferation induced by platelet-derived growth factor-BB (PDGF-BB) in MCs and blocked cell cycle progression. Likewise, inflammatory factors, including monocyte chemotactic protein 1 (MCP-1) and tumor necrosis factor alpha (TNF-α), in MCs were decreased after treatment with Justicidin B. In addition, Justicidin B exhibited antioxidant activity in PDGF-BB-induced MCs, shown by the decreased production of malondialdehyde and T-AOC, and increased the expression of superoxide dismutase. Besides, Justicidin B suppressed extracellular matrix (ECM) deposition by reducing the protein levels of collagen IV and fibronectin. Furthermore, we found that Justicidin B significantly inhibited activation of the Akt/mammalian target of rapamycin (mTOR) signaling pathway in MCs induced by PDGF-BB, but enhanced the levels of proteins in the nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase 1 (HO-1) pathway. Taken together, Justicidin B prevented PDGF-BB-induced proliferation, inflammation, oxidative stress, and ECM accumulation via regulating the activation of the Nrf2/HO-1 pathway and the Akt/mTOR signaling pathway.

Recurrent glomerular disease after kidney transplantation

PURPOSE OF REVIEW

With improving short-term kidney transplant outcomes, recurrent glomerular disease is being increasingly recognized as an important cause of chronic allograft failure. Further understanding of the risks and pathogenesis of recurrent glomerular disease enable informed transplant decisions, along with the development of preventive and treatment strategies.

RECENT FINDINGS

Multiple observational studies have highlighted differences in rates and outcomes for various recurrent glomerular diseases, although these rates have not markedly improved over the last decade. Emerging evidence supports use of rituximab to treat recurrent primary membranous nephropathy and possibly focal segmental glomerulosclerosis (FSGS), whereas eculizumab is effective in glomerular diseases associated with complement dysregulation [C3 glomerulopathy (C3G) and atypical hemolytic uremic syndrome (aHUS)].

SUMMARY

Despite the potential for recurrence in the allograft, transplant remains the optimal therapy for patients with advanced chronic kidney disease (CKD) secondary to primary glomerular disease. Biomarkers and therapeutic options necessitate accurate pretransplant diagnoses with opportunities for improved surveillance and treatment of recurrent glomerular disease posttransplant.

Predicting Post-Transplant Recurrence of IgA Nephropathy: The Importance of Crescents

BACKGROUND

Most studies that have assessed the predictors of recurrent IgA nephropathy (IgAN) in the renal allograft have focused on post-transplant features. Identifying high-risk pre-transplant features of IgAN is useful for counseling patients and may help in tailoring post-transplant immunosuppression.

METHODS

We investigated the pre-transplant clinical and biopsy features of 62 patients with IgAN who received transplants at Columbia University Medical Center from 2001 to 2012 and compared the characteristics and outcomes of patients with IgAN recurrence to those without recurrence. The primary outcome was time to recurrent IgAN. Secondary outcomes were a composite of doubling of creatinine or allograft failure, and recurrent IgAN as a cause of allograft dysfunction.

RESULTS

Of the 62 patients, 14 had recurrent IgAN in the allograft. Mean time to recurrence was 2.75 years. Those with recurrent disease were younger at the time of native kidney biopsy (29 vs. 41 years, p < 0.0009). Black race and Hispanic ethnicity composed a higher proportion of the recurrent disease group. On multivariable analysis, significant predictors of recurrent IgAN included age at diagnosis (hazards ratio (HR) 0.911, 95% CI 0.85-0.98), burden of crescents on native biopsy (HR 1.21 per 10% increase in crescents, 95% CI 1.00-1.47) and allograft rejection (HR 3.59, 95% CI 1.10-11.7).

CONCLUSIONS

Features of native IgAN can help predict the risk of recurrent disease in the renal allograft. In particular, immunologically active disease represented by earlier age of onset and greater burden of crescents on native biopsy is more likely to recur after transplant.