The prognostic features in patients with IgA nephropathy who showed severe histopathological changes were described. Fifty five patients with moderate and advanced stages of IgA nephropathy were evaluated. The mean duration of the follow up ranged from 6 to 112 months (mean : 51.2 months). These patients were divided into four groups (Typel-4) according to the mean levels of the slope of the reciprocal of serum creatinine (s-Cr) vs time plot. The histopathological changes of renal specimens, blood pressure, s-Cr, serum IgG, IgA, IgM, C3 levels, PSP (15 min), the degree of proteinuria and hematuria were examined at the time of biopsy. The averages of blood pressure and the amount of proteinuria were examined serially throughout the study period. Proteinuria, s-Cr, PSP (15 min) at the time of biopsy in Type 4 (fulminant type) were significantly increased compared with those in Type 1 (stable type). The average amount of proteinuria were also significantly increased in Type 4. It was suggested that histopathological changes of renal specimen, proteinuria of more than 1.0 g/day, s-Cr of more than 1.5 mg/dl and PSP (15 min) of less than 35% were useful to evaluate the prognosis of patients with IgA nephropathy with severe histopathological changes.
