[Blastocystosis in preschool children from bolivar city, venezuela].

To evaluate the prevalence of Blastocystis hominis and its clinical relevance, 169 preschool children from the 'Los Coquitos' nursery school living in Bolivar City, Venezuela, were studied. Stool samples were obtained and examined by direct microscopic examination, and the Faust and Willis concentration techniques. Some 72 of the children had intestinal parasites, of whom 32 (29.09%) had B. hominis. Prevalence for the latter was 18.93 % +/- 5.93 %. No differences were observed by sex or age (X(2) = 1.84 DF= 3; p > 0. 05). In the majority (53.13%) of the children, B. hominis was the only parasite. Giardia lamblia was the parasite most frequently identified with B. hominis (39.13%). In 1994, in 12% of the cases more than five microorganisms per microscopic field were observed. Clinical manifestations were observed in 70.58% of the preschool children. Presence of parasites was not correlated with symptomatology, but only with severity. Proper clinical and parasitological response to treatment was observed in 80% and 90% of patients, respectively. The conclusion was that B. hominis is a relatively frequent intestinal parasite among the preschool children evaluated.