DISCORDANT RENAL HISTOPATHOLOGIC FINDINGS AND COMPLEMENT PROFILES IN MEMBRANOPROLIFERATIVE GLOMERULONEPHRITIS TYPE-III

Patients with membranoproliferative glomerulonephritis (MPGN) type III and a low serum C3 concentration tend to have evidence for a nephriti c factor of the terminal complement pathway (NFt). Complement profiles were studied in three patients with MPGN type III and low serum C3 co ncentrations, Serum C3 concentrations were 52, 21, and 14 mg/dL (norma l range, 83 to 177 mg/dL). Serum C1q, C2, C4, properdin, and C5 concen trations were normal in all patients, whereas two had a slight decreas e of C7 or C8. This pattern of complement activation resembles that se en with MPGN type II in which a nephritic factor activates the amplifi cation loop (NFa). We conclude that in patients with MPGN type lit the previously reported profile/presence of Nft is not always found, at l east in the chronic stage of the disease, despite a low C3 value. (C) 1996 by the National Kidney Foundation, Inc.