The pathogenesis of arthropathy in experimental Schistosomiasis mansoni.

The pathogenesis of arthropathy in experimental schistosomiasis mansoni was studied. 70 Swiss albino mice were used, 14 served as control while 56 were subcutaneously infected with 80-100 Schistosoma mansoni cercariae/mouse. Mice were sacrificed at 8, 10, 12, 14, 16, 18 and 20 weeks postinfection (p.i.). Shoulder and knee joints were taken and processed for H & E stain and immunoperoxidase stain. As regards histopathological examination, 75% of infected mice showed marked pathological joint changes, with no Schistosoma ova could be detected in all examined sections. These changes appeared at the 12th week (p.i) and became more severe with the chronicity of infection. Immunohistochemical examination of the infected joints, revealed 75% positivity of schistosomal antigen deposition with mild to moderate expression (in early and late stages of infection respectively). The detection of schistosomal antigen in joints of infected mice which coincided with the histopathological affection, can be considered as the aetiological agent in induction of schistosomal arthropathy. Hence, the term reactive schistosomal arthropathy can be changed into schistosomal arthritis.