Intestinal Absorption Tests and Biopsy of the Jejunum in Subjects with Heavy Hookworm Infection*

Abstract
Summary Morphology of the peripheral blood and bone marrow was studied, and intestinal absorption tests and jejunum biopsy were performed in 22 patients harboring heavy hookworm infection. Fat absorption, measured both chemically and with oleic acid marked with I131, was normal in all but three patients who showed slight increase of excretion. d-xylose was poorly absorbed in 1 of 18 cases tested. Serum vitamin B12 concentration was significantly diminished although a value below 200 µµg per ml of serum was seen in only one case. Schilling test performed in 8 patients showed 24-hour urinary excretions of B12 Co58 of over 10 percent. On the other hand, there was low folic acid serum concentration and impairment of absorption. Morphological changes in the peripheral blood and bone marrow suggestive of either vitamin B12 or folic acid deficiency were seen in five cases. In four of these cases which were examined for serum folate activity, values below 4.6 mµg per ml of serum were found. Jejunum biopsy, performed in 18 cases, showed only slight non-specific changes in 14. Of the other 4, one showed frank atrophy of the mucosa, a second showed flattening of the mucosal surface and fusion of the villi, and the other two showed marked infiltration, especially around the crypts. The results obtained here indicate that hookworm infection per se, without the association of other factors such as malnutrition and other parasitic infections, does not as a rule lead to histological changes in the mucosa which might cause malabsorption of nutrients.