Determinants of symptomatic giardiasis in childhood.

Giardia has been frequently implicated as a causative agent for acute as well as chronic diarrheal diseases in children. The present study was aimed at exploring the determinants of manifestations of Giardiasis in childhood, in relation to various host and parasite related factors. A total of 200 children with acute (100), chronic (50) or without (50) diarrhea in last 15 days were recruited for the study and evaluated with regards to nutritional status, serum immunoglobulins, secretory IgA levels, presence of Giardia in stool/duodenal aspirate/duodenal biopsy specimen and for associated infections. Lysates from acute giardiasis cases were further studied for zymodeme (banding) pattern. After correlation of all investigations, humoral immune defect in the host was found to be the major determinant of whether the Giardial infestation would be symptomatic or not, while associated bacterial infections and zymodeme patterns were not found to be important in determining the pathogenicity or presentation of giardiasis.