Studies of the Mechanism of Postgastrectomy Steatorrhea

Abstract

Thirty postgastrectomy patients were studied, 15 without and 15 with steatorrhea, as determined by measurements of fecal fat and I131 triolein excretion. Material from the afferent loop of the gastrojejunostomy was subjected to quantitative bacterial cultures. In patients with steatorrhea, afferent loop bacteria colony counts were consistently higher than those in patients without steatorrhea; and the differences between the medians of the colony counts of patients with and without steatorrhea were statistically significant at the 0.001 level. The administration of appropriately selected antibiotics was followed by gains in weight and reductions in fat excretion in five of eight patients with steatorrhea so treated. Improvement correlated well with reductions is afferent loop bacterial counts. The data demonstrate a highly significant association between postgastrectomy steatorrhea and the development of a fecal type resident bacterial flora in the afferent loop of the gastrojejunostomy. Other factors undoubtedly participate in the causation of steatorrhea in this group of patients and may interact with factors of stasis and bacterial flora. Preliminary measurement of pancreatic enzymes of fasting afferent loop fluid suggest a reduction in lipase activity in patients with postgastrectomy steatorrhea. It was not established whether lowered lipase activity was due to decreased pancreatic function or to inactivation of secreted lipase as the result of prolonged stasis and exposure to bacteria in a poorly draining afferent loop. Studies of conjugated bile acids incubated with bacteria failed to provide evidence of deconjugation, and jejunal biopsies from seven patients with postgastrectomy steatorrhea did not show more than minimal histologic changes in the mucosa.