'For a quart of ale is a dish for a king': not always.

We report the case of a man with a clear diagnosis of coeliac disease who nevertheless drank gluten-containing beer. We found that a 4-week period of drinking gluten-containing beer did not provoke significant changes in the intestinal mucosa of this patient with coeliac disease nor did it elicit any relevant symptoms. Serum antibody levels rose but did not reach a pathological threshold. However, a more prolonged gluten challenge may have led to clinically relevant changes in IgA antitransglutaminase titres. This case demonstrates how important individual sensitivity to gluten in a patient with coeliac disease is in determining symptoms, immunological response and intestinal mucosa damage. 2016 BMJ Publishing Group Ltd.