Coeliac disease and autoimmune Addison's disease: a clinical pitfall.

BACKGROUND Coeliac disease has an increased prevalence in a number of autoimmune endocrine conditions. An association between coeliac disease and Addison's disease has been proposed in isolated case reports, but has not been formally studied. AIM To investigate the extent of this association. DESIGN Prospective screening of patients with confirmed Addison's disease. METHODS From central computerized records, we identified all living patients with a diagnosis of autoimmune Addison's disease in the past 30 years and presently attending our affiliated hospitals. After exclusions, 44 were invited to attend for screening. RESULTS Of 41 patients screened, five (12.2%) had coeliac disease: Three were previously diagnosed coeliacs and this was confirmed on review, including examination of biopsy material. A further two had positive IgA-endomysial antibodies. Histological confirmation was obtained in both cases. Neither had laboratory or clinical evidence of malabsorption. DISCUSSION In this series of patients with Addison's disease, a higher co-morbidity with coeliac disease was observed than in any previously studied endocrine condition. We recommend that coeliac serology (anti-endomysial and tissue transglutaminase antibody) testing be incorporated routinely into the autoimmune screen for other conditions in patients with Addison's disease.