Clinicopathological study of giardiasis: A retrospective descriptive study from a tertiary care center in South India

Giardia lamblia is recognized as the most prevalent intestinal parasite globally. Its clinical presentation varies from asymptomatic carrier to acute or chronic diarrhea, with immunocompromised individuals being more vulnerable. When stool examinations fail to confirm the diagnosis, duodenal aspirate microscopy is advised, though it is often laborious and uncomfortable for patients.

This retrospective study analyzed all biopsy-confirmed cases of giardiasis to evaluate their microscopic features.

This retrospective descriptive study analyzed 30 biopsy-proven duodenal giardiasis cases. Clinical, endoscopic, and histopathological parameters were reviewed, including parasite density, villous changes, lymphoid hyperplasia, and inflammation. Slides stained with hematoxylin and eosin stain and Giemsa stain were examined microscopically. Data was analyzed using descriptive statistics and expressed as frequencies and percentages.

Among 30 cases studied over 12 years, diarrhea was the predominant indication for endoscopy. Endoscopic nodularity was identified in 50% of patients, with the parasite most commonly located in the first or second part of the duodenum. Moderate lamina propria inflammation was present in 77% of cases. Diffuse nodular lymphoid hyperplasia was noted in 11 cases, including two with follicular diameters of 720 µm and 900 µm. Villous morphology varied from normal to varying degrees of flattening, blunting, and atrophy.

Mucosal nodularity was frequently observed with moderate inflammation of lamina propria. The presence of lymphoid follicles in biopsies may serve as a soft clue. Vigilant searches for Giardia trophozoites should be done in such biopsies.