ANTI-SACCHAROMYCES CEREVISIAE MANNAN ANTIBODIES IN FAMILIAL CROHNS-DISEASE

Objective: Anti-Saccharomyces cerevisiae mannan antibodies (ASCA) are associated with Crohn's disease. The aim of this study was to determin e the prevalence of ASCA in families in which at least two members wer e affected with Crohn's disease. Methods: A total of 20 families inclu ding two (n = 15) or more (n = 5) patients with Crohn's disease were t ested for ASCA with use of an ELISA method, Overall. 51 affected membe rs, 66 healthy first degree relatives, and 163 healthy control subject s were studied. Results: ASCA were detected in 35 of 51 (69%) patients with Crohn's disease and in 13 of 66 (20%) healthy relatives versus o ne of 163 healthy control subjects (p < 0.0001 and p < 0.001), ASCA-po sitive relatives were distributed in 12 of 20 families. ASCA were pres ent in eight healthy parents and four healthy siblings, The prevalence of ASCA in relatives did not depend on the ASCA status of affected me mbers. Conclusion: ASCA in 20% of healthy first degree relatives of pa tients with Crohn's disease suggest that these antibodies might be a s ubclinical marker for Crohn's disease in families. Whether ASCA reflec t environmental or genetic factors or a combination of both is unknown . (Am J Gastroenterol 1998;93: 1306-1310. (C) 1998 by Am. Coll. of Gas troenterology).