The association between primary biliary cirrhosis and coeliac disease: a study of relative prevalences.

BACKGROUND Coexistent primary biliary cirrhosis (PBC) and coeliac disease has been recorded but the association has not been systematically studied. AIMS To determine relative prevalences of PBC and coeliac disease in a defined population over a 12 year period. PATIENTS AND METHODS All patients with PBC or coeliac disease in a stable population of 250,000 in South Wales were identified from a clinical register and laboratory records. RESULTS Sixty seven patients with PBC and 143 patients with coeliac disease have been diagnosed and followed over a median of 86 (4-135) months; point prevalences in 1996 were 20 per 100,000 for PBC and 54 per 100,000 for coeliac disease. PBC in patients with coeliac disease was sought by investigating abnormal liver function tests. Ten (7%) had persistent abnormalities and three had PBC. Coeliac disease in patients with PBC was sought by investigating malabsorption, haematinic deficiency, positive antigliadin antibody, or coeliac disease family history. Eleven patients underwent duodenal biopsy revealing one further coeliac disease case. Four patients (three women have both conditions giving a point prevalence for patients with both conditions of 1.6 per 100,000 (95% confidence limits 0.44 to 4.1 per 100,000). Prevalence of PBC in patients with coeliac disease was 3% and of coeliac disease in patients with PBC was 6%. CONCLUSION A 12 year study of a stable 250,000 population revealed a relative prevalence of PBC in 3% of 143 patients with coeliac disease and of coeliac disease in 6% of 67 patients with PBC. PBC and coeliac disease are therefore associated. Screening for PBC in patients with coeliac disease using antimitochondrial antibody testing and screening for coeliac disease in patients with PBC with antigliadin antibody testing or duodenal biopsy are recommended.