Myocardial affection in mice infected with Schistosoma mansoni: histopathologic and immunofluorescent observations

ABSTRACT

20 Swiss albino mice were exposed to cercarial infection of Schistosoma mansoni shedded from Biomphalaria Alexandrina snails. A group of non-infected mice were used as negative controls. An animal was sacrificed every 2 weeks from the 8[th] week following infection till the 46[th] week. Hearts of both groups were removed and specimens were sent for light microscopic and direct immunofluorescent examination. Histopathologic study revealed granulomatous schistosomatic myocarditis in 3 mice. There were no muscle fibre degeneration or attenuation, no interstitial fibrosis or mononuclear cell infiltration [apart from the schistosomal granulomas] and no endocardial affection. Vascular immunofluorescence for schistosomal egg antigen [SEA] was observed in 6 mice. The reaction was linear involving one or more layers of the coating wall. Positive immunofluorescence for SEA appeared also within the granulomatous reaction in the hearts of the 3 affected mice. No specific immunofluorescent deposits were detected over the myofibers in the infected group at any stage of infection. Thus, myocardial affection in mice infected with schistosoma mansoni was minimal. The relevance of these results to other studies and to observations in schistosomal patients was discussed