Recurrence and graft loss after renal transplantation in adults with IgA vasculitis

Extracellular CIRP co-stimulated T cells through IL6R/STAT3 in pediatric IgA vasculitis

Immunoglobulin A vasculitis (IgAV) is the most common vasculitis of childhood. Disordered immune responses play important roles in its pathogenesis, but the comprehensive immune profile of the disease and the underlying mechanisms are still largely unknown. Here we found a potential disease biomarker cold inducible RNA binding protein (CIRP) in our pediatric IgAV cohort. Serum CIRP level in these patients were elevated and positively correlated with the increased early memory (CD45RA+CD62L+CD95+) T cells revealed using multicolor flow cytometry. Immune phenotyping of the patients showed they had more activated T cells with higher IL6Ra expression. T cell culture experiment showed CIRP further activated both human CD4+ and CD8+ T cells as indicated by increased perforin secretion and phosphorylation of STAT3. Blockade of IL6Rα attenuated CIRP-induced T cell toxicity in vitro. RNA-sequencing data further supported CIRP stimulation promoted human T cell activation and migration, fueled inflammation through the JAK-STAT signaling pathway. Therefore, IL6Ra-mediated T cell activation by extracellular CIRP may contribute to pathogenesis of IgAV in children, both CIRP and IL6Ra could be new therapeutic targets for IgAV.

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.

Current Status and Perspectives on Recurrent IgA Nephropathy after Kidney Transplantation

IgA nephropathy (IgAN) is the most common form of glomerulonephritis worldwide. IgAN progresses to end-stage kidney disease in 20-40% of patients within 20 years of diagnosis. Kidney transplantation is the most effective option for patients with end-stage kidney disease caused by IgAN, but recurrence can occur in the transplanted kidney. The IgAN recurrence rate varies from 1% to 10% per year and varies according to the follow-up period, diagnostic modality, and biopsy criteria. Of note, studies based on protocol biopsies have reported a higher incidence of recurrence, which also occurred earlier after transplantation. In addition, recent data show that recurrence of IgAN is a more significant cause of allograft failure than previously believed. Little is known about the pathophysiology of IgAN recurrence, but several potential biomarkers have been investigated. Among them, galactose-deficient IgA1 (Gd-IgA1), IgG anti-Gd-IgA1 antibodies, and soluble CD89 could play a pivotal role in disease activity. This review aims to describe the current status of recurrent IgAN, including the incidence, clinical characteristics, risk factors, and future perspectives, with a focus on the available therapeutic approaches.

Antibody-Mediated Rejection and Recurrent Primary Disease: Two Main Obstacles in Abdominal Kidney, Liver, and Pancreas Transplants

The advances in acute phase care have firmly established the practice of organ transplantation in the last several decades. Then, the next issues that loom large in the field of transplantation include antibody-mediated rejection (ABMR) and recurrent primary disease. Acute ABMR is a daunting hurdle in the performance of organ transplantation. The recent progress in desensitization and preoperative monitoring of donor-specific antibodies enables us to increase positive outcomes. However, chronic active ABMR is one of the most significant problems we currently face. On the other hand, recurrent primary disease is problematic for many recipients. Notably, some recipients, unfortunately, lost their vital organs due to this recurrence. Although some progress has been achieved in these two areas, many other factors remain largely obscure. In this review, these two topics will be discussed in light of recent discoveries.

Distinct characteristics and outcomes in elderly-onset IgA vasculitis (Henoch-Schönlein purpura) with nephritis: Nationwide cohort study of data from the Japan Renal Biopsy Registry (J-RBR)

BACKGROUND

The clinical presentation and prognosis of adult and elderly patients with IgA vasculitis (Henoch-Schönlein purpura) accompanied by nephritis (IgAV-N) have not been investigated in detail. We therefore surveyed the features and outcomes of IgAV-N based on nationwide data derived from the Japan Renal Biopsy Registry (J-RBR).

METHODS

This multi-center cohort study compared the clinicopathological parameters at diagnosis, initial therapies and outcomes between 106 adult (age 19-64 years) and 46 elderly (≥65 years) patients with IgAV-N who were registered in the J-RBR between 2007 and 2012. The primary end-points comprised a 50% increase in serum creatinine (sCr) values or end-stage kidney disease. Factors affecting a decrease in renal function were assessed using Cox proportional hazards models.

RESULTS

Rates of hypertension, impaired renal function, hypoalbuminemia and crescentic glomerulonephritis were significantly higher among the elderly, than the adult patients. About 80% and 60% of the patients in both groups were respectively treated with corticosteroid and a renin-angiotensin system (RAS) blockade. Both groups had favorable renal survival rates for nine years (93.6% and 91.4% of the adult and elderly patients, respectively). Significantly more elderly than adult patients developed a 50% increase in sCr during a mean observation period of 3.9 years (21.7% vs. 4.7%, p = 0.012), and significantly fewer elderly, than adult patients achieved clinical remission (23.9% vs. 46.2%, p = 0.016). Multivariate analysis selected advanced age (≥65 years) and lower serum albumin values as independent prognostic factors for a decline in renal function, whereas steroid pulse therapy helped to preserve renal function.

CONCLUSIONS

The renal prognosis of adult and elderly patients with IgAV-N was favorable when treated aggressively with corticosteroid and RAS blockade. However, the course of renal function should be carefully monitored in patients aged over 65 years and those with hypoalbuminemia.

IgA Vasculitis: Genetics and Clinical and Therapeutic Management

PURPOSE OF REVIEW

The purpose of the study is to perform an update on the current knowledge on genetics, clinical manifestations, and therapy in immunoglobulin A vasculitis (IgAV) (Henoch-Schönlein purpura).

RECENT FINDINGS

A strong genetic predisposition in individuals with IgAV was confirmed. It was due to the association with the HLA class II region that in people of European background is mainly related to HLA-DRB1*01 allele. Recent reports support the claim that kidney disease is more common in adults than in children with IgAV. The clinical spectrum and outcome of adults with IgAV depends on the age of onset. Relapses are not uncommon in IgAV. The presence of renal impairment or proteinuria excretion exceeding 1 g/24 h at the time of disease diagnosis and the degree of renal damage on the kidney biopsy are the best predictors of end-stage renal failure in adults with IgAV. The levels of urinary IgA at the onset of the disease may predict a poor renal outcome. The use of prednisone does not seem to prevent persistent kidney disease in children with IgAV. No additional benefit of adding cyclophosphamide to glucocorticoids in adults with IgAV was found. Rituximab seems to be a promising therapy in the management of adults with IgAV. In this overview, we focus on the genetics, clinical manifestations, and therapy of IgA vasculitis, emphasizing the main differences in the clinical expression of the disease between children and adults.