Use of whole-gut lavage to measure intestinal immunity in healthy Sierra Leonean children.

In view of the potential roles of intestinal immunodeficiency and hypersensitivity in the infection/diarrhea/malnutrition cycle, we need a safe and ethical method to study intestinal immunity of children in the developing world. Work in adults has shown that the fluid obtained by whole-gut lavage (WGLF), essentially a gut perfusate, can be used to assess intestinal immunity, inflammation, and gut losses of protein and blood. Gut lavage was successfully performed in 24 of 25 "normal" children aged 6-9 years, from Freetown, Sierra Leone, with parental informed consent. WGLF was treated with protease inhibitors, stored at -20 degrees C, and transferred to Edinburgh for laboratory studies. These showed that no child had occult blood loss but four had evidence of protein-losing enteropathy. Compared with values for Scottish adults, WGLF from the Sierra Leonean children had significantly higher concentrations of IgA and IgM and of IgA and IgM antibodies to dietary antigens and to Salmonella typhi lipopolysaccharide. In three children, very low levels of IgA and IgA antibody were present: Two of these were the only cases with detectable sIL2R in lavage fluid, indirect evidence of intestinal T cell activation; tumor necrosis factor was not detectable. Substantial information on childrens' intestinal immunity can be obtained by the method described.