Histological and histomorphometric evaluation of the retina of mice infected with Schistosoma mansoni in its hepatosplenic form.

Purpose: To evaluate retinal manifestations of Schistosomiasis mansoni in its hepatosplenic form in mice.
Methods: It was performed a study with two groups of mice; one of them was infected with 40 cercariae of Schistosoma mansoni. After 120 days of the infection, the eyes underwent a retinal microscopy study. The histology findings were reported. Histomorphometric analysis was also performed, including: thickness measurement of the retinal layer and the number of the ganglion layer cells.
Results: In one case a retinal granuloma was found. The analysis of the other histological sections demonstrated normal architecture of the retina. The mean thickness of the retinal layer between the two groups were similar (41.81+/-6.09 microm versus 38.48+/-8.58 microm - p=0.279); as well as the mean number of the ganglion layer cells (20.93+/-4.88 versus 20.64+/-4.10 - p=0.864). Disorganization of the retinal layers was not identified and the histomorphometric analysis revealed no significant difference between the two groups.
Conclusion: The absence of findings in this study does not exclude that hemodynamic and autoregulation changes associated with hepatosplenic schistosomiasis could be correlated to retinal manifestations. It is necessary that other methods with a high parasite infection should be performed.