Coeliac disease associated with Sjögren's syndrome, renal tubular acidosis, primary biliary cirrhosis and autoimmune hyperthyroidism.

Although coeliac disease may occur in patients affected by another immune-mediated disorder, its coexistence with multiple autoimmune diseases is not frequently described. We report here the case of a 45-year-old woman referred to our centre because of diarrhoea and weight loss, who had already received a diagnosis of primary biliary cirrhosis, Sjögren's syndrome and renal tubular acidosis. Following the development of diarrhoea we established the diagnosis of coeliac disease, based on the presence of anti-endomysium antibodies and a compatible duodenal biopsy. Despite gluten withdrawal she went on to develop an autoimmune hyperthyroidism. The patient tested positive for HLA DRB103 and DQB102. The association is unlikely to be casual and may be explained by autoimmune mechanisms, genetic susceptibility and favouring environmental factors commonly shared by the diseases of our patient.