Giardiasis and Severe Chronic Enteritis in a Dog

History: 11-year-old Poodle, spayed female, showing severe hypoalbuminemia and hypoglobulinemia along with mild ascites of 3-4 week duration. Serum bile acids (pre and post prandial) are within normal limits.

Cytological description: The smears are from fine-needle biopsies of the small intestine. These show scattered medium-sized clusters of intestinal cuboidal to columnar epithelial cells severely invaded by multiple small lymphocytes. There are also multiple Giardia trophozoites. These organisms are pear-shaped, 8-10 x 12-15 microns, binucleated and flagellated.

Comments: Giardia organisms infect the proximal small intestine where they interfere with mucosal function. Motile trophozoite attach to the brush border surface of the mucosal epithelium and cause diarrhea secondary to intestinal malabsorption. In this case, the chronic enteritis could be secondary to Giardia or could be a concomitant finding.

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