Schistosomal specific nephropathy leading to end-stage renal failure

In this study 17 patients, 11 with end-stage renal failure and six with nephrotic syndrome were selected. The selection criteria were presence of active intestinal schistosomiasis and absence of any surgical or other medical disease which could explain the renal disease. When examined by light microscopy, kidney biopsies showed membranoproliferative glomerulonephritis in nine, membranous in four, focal segmental glomerulosclerosis in two, sclerosing glomerulonephritis in one case, and no changes in another case. Direct immunofluorescence showed IgG deposits in 13 cases, IgM in 10 and different complement components (C3, C1q) in eight cases. Eluates from the kidney biopsies of the 17 schistosomal as well as six control cases were examined by ELISA against schistosoma mansoni adult worm antigen (AWA). This test showed the presence of antibodies against the AWA in 12 out of 17 of the schistosomal cases, and zero out of six of the controls. When examined by direct IFA using sheep anti-circulating anodic antigen/FITC and by indirect IFA using monoclonal antischistosomal CAA IgG3, kidney biopsies of the ELISA positive cases showed granular deposits of circulating anodic antigen (CAA). We conclude that schistosomal specific nephropathy does exist in the clinical settings and can lead to end-stage renal disease, with CAA probably being a major responsible antigen.