BACKGROUND: The protozoan parasite Cryptosporidium parvum, which causes acute gastroenteritis in both humans and animals, has become an important pathogen all over the world. C. parvum may cause asymptomatic or symptomatic acute infections of the digestive system in immunocompetent subjects, but life-threatening disease in immunocompromised hosts. The aim of this study was to determine the usefulness of conventional microscopic staining techniques in the detection of C. parvum. For this purpose, 50 unselected immunocompetent asymptomatic children were evaluated for C. parvum during routine upper endoscopy. MATERIAL/METHODS: Duodenal aspirates and duodenal biopsy samples from 37 girls and 13 boys, between the ages of 2 and 18 years, obtained by gastrointestinal upper endoscopy and concomitant stool samples were examined with different staining techniques. RESULTS: Two stool samples and one duodenal aspirate were positive for C. parvum, but we could not demonstrate C. parvum in any duodenal biopsy samples. Dyspepsia was the primary indication for upper endoscopy in the patient with positive duodenal aspirate sample. CONCLUSIONS: These findings indicate that there is a low asymptomatic carrier rate in immunocompetent subjects with no involvement of intestinal villius attachment in the duodenum. We also conclude that C. parvum is an infrequent parasite in asymptomatic subjects, most probably due to a very low prevalence of HIV positivity in Turkey.

Keywords: Carrier State - diagnosis, Carrier State - parasitology, Cryptosporidiosis - diagnosis, Cryptosporidiosis - parasitology, Cryptosporidium parvum - isolation & purification, Oocysts - isolation & purification, Parasitology - methods