To identify the source of intestinal blood loss in rheumatoid arthritis patients being treated with nonsteroidal antiinflammatory drugs (NSAIDs) and assess the response to sulfasalazine and other disease-modifying antirheumatic drugs (DMARDs).
Intestinal inflammation, blood loss, and gastroduodenal damage, and the response to treatment with DMARDs, were assessed in 46 patients taking NSAIDs.
Intestinal inflammation and blood loss correlated significantly with one another (r = 0.43, P < 0.003), but not with the macroscopic or microscopic appearance of the gastroduodenal mucosa. Sulfasalazine reduced both intestinal inflammation and blood loss, whereas the other DMARDs did not.
The small intestine is the main site of mild chronic blood loss in patients receiving NSAIDs, and this blood loss can be reduced with sulfasalazine treatment.