Collapsing glomerulopathy coexisting with membranous glomerulonephritis in native kidney biopsies: a report of 3 HIV-negative patients.

Collapsing glomerulopathy (CG), a variant of idiopathic focal segmental glomerulosclerosis (FSGS), can occur in both human immunodeficiency virus (HIV)-positive and HIV-negative patients. Idiopathic membranous glomerulonephritis (MGN) has been reported to coexist with FSGS, but rarely with CG. We report 3 HIV-negative patients (2 men, 1 woman) who developed nephrotic syndrome secondary to MGN complicated by CG, with relatively rapid disease progression despite aggressive therapy.