Human giardiasis. A morphometric study of duodenal biopsy specimens in relation to the trophozoite count in the duodenal aspirate.

We present a morphometric analysis of findings from a histopathologic study of duodenal giardiasis in relation to the trophozoite count in the duodenal aspirate. Of 30 patients with giardiasis whose conditions were studied, a mean trophozoite count of 10(3)/mL or greater was found in 21, and a mean trophozoite count of less than 10(3)/mL was found in nine--these two types of trophozoite counts in these 30 patients represented the acute phase (group 1) and the clearance phase (group 2) of giardiasis, respectively. Group 1 patients had a low mean villus height that was significantly less than that found in the control subjects. Group 2 patients had a high mean crypt depth that was significantly greater than that found in the control subjects. Partial villus atrophy was seen in only seven of the group 1 patients, including five with villus epithelial cell lesions. Groups 1 and 2 showed minor differences of an inflammatory response that was significantly greater than that shown in the control subjects.