Human schistosomiasis: Schistosoma mansoni antigen detection in renal glomeruli

Abstract

Twelve kidney, five biopsy and seven necropsy specimens, all from schistosomiasis mansoni patients were studied by light and immunofluorescent microscopy in an attempt to detect antigen in the glomerular walls. Deposits of IgM, IgG, IgA, IgE, complement C3 and fibrinogen were observed in most cases. Antigen was successfully detected in two cases (one biopsy and one necropsy specimen), both exhibiting proliferative glomerulonephritis. The only clinical manifestation was a slight proteinuria. IgG antibodies eluted from the autopsy kidney homogenates showed specific binding mostly to Schistosoma mansoni gut, thus suggesting that the fixed antibodies (eluates) are, at least partially, constituted by antibodies similar to the anti-circulating antigen. These data reinforce the hypothesis that renal injury in schistosomiasis is mediated through an immune complex disease.