Decreased anti-Saccharomyces cerevisiae antibody titer by mesalazine in patients with Crohn's disease

Background: Saccharomyces cerevisiae may contribute to the pathophysiology of Crohn's disease. We determined serum anti-Saccharomyces cerevisiae antib ody (ASCA) levels in patients with inflammatory bowel disease. Methods and Results: Immunoglobulin G (IgG) ASCA was measured by using an E LISA in serum samples from 19 patients with ulcerative colitis, 18 patients with Crohn's disease and 7 healthy controls. The ASCA level was significan tly higher in patients with ulcerative colitis and patients with Crohn's di sease than in controls, and was significantly higher in patients with Crohn 's disease compared with patients with ulcerative colitis. Age, gender, dis ease activity, extent of disease and small bowel involvement: each did not affect ASCA levels. The use of elemental or polymeric diet therapy for Croh n's disease and administration of corticosteroids to patients with inflamma tory bowel disease also did not affect ASCA levels. The ASCA titer was sign ificantly lower in patients with Crohn's disease taking mesalazine than in those not taking it, although, serum IgG levels did not differ between thes e two groups, which might imply a suppression of IgG production by mesalazi ne at the intestinal level. Conclusions: The finding of increased serum ASCA titers in patients with in flammatory bowel disease suggests that Saccharomyces cerevisiae may play a role in the pathophysiology of this condition. (C); 2000 Blackwell Science Asia Pty Ltd.