Hepatic fibrosis in the pathogenesis of schistosomal glomerulopathy cannot be explained by any positive influence of hepatocellular injury. In order to examine the potential role of impairment of hepatic macrophage function, the t1/2 plasma clearance of 99mTc-sulphur colloid was studied in 30 patients with schistosomal glomerulopathy, ten normal volunteers, ten cases of uncomplicated intestinal schistosomiasis, ten non-schistosomal cirrhotic patients and ten non-schistosomal nephrotic patients. Liver and renal biopsies were obtained from appropriate groups and examined by light microscopy and glomerular immunofluorescence. There was a significant correlation between t1/2 of sulphur colloid clearance and proteinuria, mesangial hypercellularity, and predominance of IgA glomerular deposits. These data indicate that hepatic macrophage dysfunction is an important factor in the pathogenesis of schistosomal glomerulopathy, and that IgA plays a major role in advanced glomerular lesions. The degree of impairment of hepatic macrophage function may influence the pattern and severity of glomerular lesions depending upon the affection of IgA clearance mechanisms.