Cryptosporidiosis in immunocompetent children.

Cryptosporidial oocysts were identified by modified Ziehl-Neelsen stain in the stools of seven (3.2%) of 213 children with acute or chronic diarrhoea and one (0.9%) of 112 controls. All children with cryptosporidia were immunocompetent. Four of the index cases had a short illness (3-14 days) with watery diarrhoea, vomiting (2), and abdominal pain (2). Two index cases had chronic diarrhoea for over four months and failure to thrive. Both had a small intestinal enteropathy; one had cryptosporidial oocysts in stool specimens two months apart and the other had cryptosporidial schizonts attached to the jejunal mucosa. One index case had a colitis of indeterminate cause. Four of the index cases had recently travelled abroad. There had been an outbreak of gastroenteritis in the family of one of the index cases, and three affected sisters and an asymptomatic brother had oocysts in their stools. Cryptosporidial infestation seems to be associated with acute gastroenteritis and sometimes with chronic diarrhoea and small bowel damage in immunocompetent children.