Histopathological and immunofluorescence study of the choroid plexus in hepatosplenic schistosomiasis mansoni

A histopathological and immunofluorescence (IMF) study of the choroid plexus was performed in 8 cases of hepatosplenic schistosomiasis mansoni and in 20 cases which had resulted in death with no evidence of liver or brain involvement by schistosomiasis or other disease process, and in which renal disease and arterial hypertension were also excluded (control group). IgA, IgG, IgM, C3, and C1q were investigated. Positive IMF in the choroid plexus was found in 75% of the schistosomiasis group. IgA and IgG were the immunoglobulins (Ig) most frequently found. C3 was also commonplace. Histologic examination of the choroid plexus showed changes in 87.5% of the schistosomiasis group. The most frequently found change was characterized by focal, linear, occasionally nodular, subepithelial deposition of a homogeneous, acidophilic, and PAS positive substance, apparently in relation to the epithelial basement membrane, with thickening of this structure. In the control group, the IMF in the choroid plexus was negative in all cases, and only 2 cases (10%) presented histopathological changes of the choroid plexus with a pattern similar to that of the schistosomiasis group. The demonstration of the deposition of Ig and fractions of the complement system, and of histological changes in the choroid plexus in a liver disease which is known to exhibit circulating immune complexes and glomerulopathy with deposition of Ig and fractions of the complement system suggests an etiopathogenetic relationship between both findings.