Mechanism of malabsorption in giardiasis: A study of bacterial flora and bile salt deconjugation in upper jejunum

Abstract

63 unselected cases of giardiasis, with no evidence of other systemic disease, were screened for evidence of steatorrhoea. No patient had any evidence of protein-energy malnutrition. 17 (27%) of the cases had steatorrhoea; 3 (17.8%) of the 17 patients having steatorrhoea also had D-xylose malabsorption. Vitamin B12 absorption was normal in all. Bacterial culture and qualitative analysis of bile salt in jejunal fluid was carried out in all the 17 cases having steatorrhoea as well as 13 cases with normal absorptive parameters (8 cases of irritable bowel syndrome and 5 cases of giardia infection) who served as controls. Significant bacterial overgrowth was noted in 8 of the 17 cases and in none of the 13 controls. All the patients showing bacterial overgrowth had free bile acids in their duodenal aspirate. Free bile acids could also be detected in jejunal aspirates of 5 of the 7 patients having no bacterial overgrowth. Two control cases of giardia infection with normal small bowel function and sterile duodenal aspirate showed evidence of bile salt deconjugation. The significance of these findings is discussed in relation to the pathogenesis of steatorrhoea in patients with giardiasis. The possible role of giardia in bile salt deconjugation is suggested.