IgA Nephropathy

Abstract

Previous studies of IgA nephropathy have demonstrated a number of prognostically significant clinical and pathological factors in groups of patients with the full histological spectrum of the disease. Whether these factors can be applied to a group of IgA nephropathy patients with disease of moderate degree is unknown. Forty patients (9 females, 31 males) with grade III IgA nephropathy (no more than 10% obsolete glomeruli and little or no interstitial fibrosis) were evaluated with respect to age, sex, degree of proteinuria, history of recurrent gross hematuria, hypertension, extent and type of segmental glomerulosclerosis, demonstration of IgG and/or IgM in deposits, presence of peripheral capillary deposits, whether or not there were crescents, and extent of vascular sclerosis. The mean age was 29.6 .+-. (SD) 13.1 years. Sixteen patients presented with recurrent gross hematuria, and 24 had microscopic hematuria and proteinuria as the initial manifestation. Hypertension was seen in 5 patients. The mean serum creatinine concentration was 1.09 .+-. 0.47 mg/dl (96.4 .+-. 41.5 .mu.mol/l), and the mean 24-hour urinary protein was 1.5 .+-. 1.3 g. Nine patients had proteinuria .gtoreq. 2.0 g/24 h. Thirty-two patients demonstrated segmental glomerulosclerosis in their biopsies, 13 of which had more than 10% of the glomeruli involved. Seven patients developed established renal failure (Cr .gtoreq. 2.0 mg/dl; 176.8 .mu.mol/l). The 60- and 100-month renal survival rates were 96 and 52%. Life table analysis disclosed that only the degree of proteinuria (.gtoreq. 2.0 g/24 h; p < 0.05) and the extent of segmental glomerulosclerosis (p < 0.025) were of prognostic significance. The two factors appear to be interrelated.