Membranoproliferative glomerulonephritis with partial lipodystrophy: discordant occurrence in identical twins.

The course of disease of a patient with membranoproliferative glomerulonephritis and partial lipodystrophy is described. The case is further characterized by a deficiency of C3 and C3- activator, by normal values of C4, by evidence of the nephritogenic factor, by raised fibrin degradation products and by an unselective proteinuria. The course of the glomerulonephritis runs parallel to a pronounced susceptibility to infection (at first varicella, tonsillitis and measles, later pneumonia, meningitis, encephalitis and hepatitis). On account of a nephrotic syndrome and an initative impairment of the renal function, a cytostatic treatment was begun, which although raising the C3 level did not influence the further course of the disease. As the patient has a healthy identical twin sister without lipodystrophy, who shows no reduction in C3 and no nephritogenic factor, this case proves that these diseases are acquired and not genetically determined.