Mesangial IgM deposition predicts renal outcome in patients with IgA nephropathy: a multicenter, observational study.

Mesangial IgM deposition is found in patients with immunoglobulin A nephropathy (IgAN). This study aims to investigate the relationships between mesangial IgM deposition and disease progression in IgAN patients. A total of 1239 patients with biopsy-proven primary IgAN were enrolled in this multicenter, observational study between January 2013 and August 2017. According to the degree of IgM deposition, 1239 patients were divided into three groups: Grade 0 (no or trace; n = 713, 57.55%), Grade 1 (mild; n = 414, 33.41%), Grades 2 + 3 (moderate and marked; n = 112, 9.04%). Using a 1:1 propensity score matching (PSM) method identifying age, gender and treatment modality to minimize confounding factors, 1042 matched patients (out of 1239) with different degrees of IgM deposition were enrolled to evaluate the severity of baseline clinicopathological features and renal outcome: Grade 0 (n = 521, 50.00%), Grade 1 (n = 409, 39.25%), Grades 2 + 3 (n = 112, 10.75%). Kaplan-Meier and Cox proportional hazards analyses were performed to determine whether different degrees of mesangial IgM deposition are associated with varying renal outcomes in IgAN. During a mean follow-up of 48.90 ± 23.86 and 49.01 ± 23.73 months, before and after adjusting for propensity scores, respectively, the rate of complete remission (CR) was progressively lower with increased IgM deposition in both unmatched (63.39%, 46.14%, 45.54%) and matched cohort (61.80%, 46.45%, 45.54%), whereas the proportion of patients progressing to end-stage renal disease (ESRD) showed reverse correlation (P < 0.001). Kaplan-Meier analysis indicated negative correlation between the intensity of mesangial IgM deposits and cumulative renal survival (all P < 0.05). Moreover, Cox regression analysis revealed that the degree of mesangial IgM deposition predicted renal outcome independent of MESTC score and clinical variables in the unmatched (Grade 1, HR, 1.59; 95% CI, 1.11-2.29; P = 0.01; Grades 2 + 3, HR, 1.69; 95% CI, 1.02-2.08; P = 0.04) and matched cohort (Grade 1, HR, 1.84; 95% CI, 1.19-2.85; P = 0.01; Grades 2 + 3, HR, 1.91; 95% CI, 1.01-3.24; P = 0.04). Mesangial IgM deposition is associated with histological activity, clinical severity and renal outcome and is an independent risk factor for poor renal prognosis in IgAN. TRIAL REGISTRATION: TCTR, TCTR20140515001. Registered May 15, 2014, http://www.clinicaltrials.in.th/index.php?tp=regtrials&menu=trialsearch&smenu=fulltext&task=search&task2=view1&id=1074 .

Crescent lesions are not a predictive factor in adult-onset Henoch-Schönlein purpura nephritis.

Henoch-Schönlein purpura nephritis (HSPN) is a common secondary glomerulonephritis, and its prognosis mainly depends on the severity of renal impairment. To date, the significance of crescent lesions in adult-onset HSPN is still unclear. Therefore, the purpose of this research was to assess whether crescents could predict the renal outcomes in adult HSPN patients. A total of 188 adult patients with HSPN proven by renal biopsy were enrolled in this prospective study. Patients were divided into three groups based on the proportion of crescents: non-crescent group (C0, n = 110), crescent ≤ 25% group (C1, n = 50) and crescent > 25% group (C2, n = 28). The composited endpoint was defined as eGFR decreased > 50% of baseline level, reached end-stage renal disease and/or death. Among three groups, clinical pathological features, treatment regimens and renal outcomes were compared. During a mean follow-up of 26 months, 78 (42.5%) patients had crescent lesions. A total of ten (9.1%) patients in C0 group and five (17.9%) patients in C2 group reached the combined endpoint, but no patients in C1 group reached endpoint. Renal survival analysis indicated patients in C1 group tended to have the best renal outcome, while patients in C2 group had the poorest renal survival. Moreover, Cox regression analysis revealed crescents were not a predictor of poor developing to renal outcome after adjusting potential confounders [hazard ratio (HR) = 0.28, 95% confidence interval (CI) 0.07-1.18, P = 0.083]. Crescent formation is not necessarily a predictive factor of poor renal survival in adult HSPN patients who had small proportions of crescents (crescent ≤ 25%).