Pathological study of intrauterine infection to embryos by Encephalitozoon cuniculi spores in pregnant mice

This study aimed to investigate pathology of oral E. cuniculi infection during pregnancy in pregnant mice and embryos. A total of 40 pregnant mice at first day of gestation were divided into two groups, first group were infected orally by E. cuniculi sores of 10 spores/ mice, second group left without any treatment. At 18 days of gestation all pregnant mice were euthanized. Gross pathology finding in pregnant mice of infected group included congestion of liver and lung, the embryos lesions consisted from enlargement of head and abdomen. Histological lesions in pregnant mice of infected group consisted of hepatic non-suppurative granulomatous lesions with E. cuniculi spores aggregation with lymphocytic infiltration, the lungs lesions consisted of infiltration of lymphocytes with E. cuniculi spores, kidney lesions composed from degenerative and necrotic changes in renal tubules, brain lesions consisted from lymphocytic infiltration with increase in number of glial cells, while intestine tissue sections showed hyperplasia of lymphatic tissue with present of parasitic vacuoles at tips of villi, the placenta exhibited E. cuniculi spores with hyperplasia of trophoblast in chorionic villi, while histological lesions in embryos showed lymphocytic infiltration around alveoli with hyperplasia of lymphatic tissue around bronchioles with absent the normal architecture of hepatic cords and vacuolation of hepatocytes with hyperplasia of lymphocytes in white pulp of spleen. This study provides insight into the pathology of E. cuniculi infection in pregnant mice and their embryos, also supports the hypothesis of intrauterine transmission of E. cuniculi infection to embryos during pregnancy period.