Diagnosis of giardiasis in infants and children by endoscopic brush cytology.

Eight pediatric patients with presenting symptoms of chronic diarrhea, abdominal cramps, weight loss, and/or recurrent emesis were diagnosed as having giardiasis by duodenal brush cytology. All patients had at least three stool specimens examined for ova and parasites, which failed to reveal Giardia lamblia cysts or trophozoites. In each patient, the small intestinal mucosal biopsies as well failed to reveal giardia. No complications were encountered during any of the procedures. Duodenal brush cytology for giardiasis appears to be a valuable diagnostic adjunct potentially superior to stool examination as well as endoscopic grasp small bowel biopsy.