The prevalence of occult gastrointestinal bleeding in celiac sprue.

BACKGROUND: Iron deficiency complicating celiac sprue is usually attributed to the malabsorption of dietary iron or the loss of iron from the intestinal mucosa. There has been little investigation of the role of intestinal loss of blood in patients with this condition. The purpose of this study was to determine the prevalence of occult gastrointestinal bleeding in patients with celiac sprue.
METHODS: We tested one 48- or 72-hour stool collection from each of 8 patients with partial villous atrophy and 28 patients with total villous atrophy using a guaiac-impregnated card (Hemoccult). Serving as controls were 18 normal subjects, each studied before and during laxative-induced diarrhea; 17 patients with idiopathic chronic diarrhea; 63 patients with microscopic colitis; 23 patients with pancreatic steatorrhea; and 7 patients with treated celiac sprue who had normal intestinal histologic features. All the patients underwent a diagnostic workup that included esophagogastroduodenoscopy, colonoscopy, and barium radiography of the small bowel.
RESULTS: Positive Hemoccult tests were infrequent in each of the control groups, occurring in 0 to 8 percent of the subjects, whereas 2 of the 8 patients with partial villous atrophy (25 percent) and 15 of the 28 patients with total villous atrophy (54 percent) had positive tests. When the patients with total villous atrophy were classified according to their subsequent responses to a gluten-free diet, 7 of the 17 who were responsive to gluten withdrawal (41 percent) were Hemoccult-positive, as compared with with 8 of the 11 who did not respond to the diet (73 percent).
CONCLUSIONS: Occult gastrointestinal bleeding can be detected in about half of patients with celiac sprue and should be added to the list of factors that can contribute to iron deficiency in patients with this disorder.