160 consecutive patients with primary biliary cirrhosis (PBC) (M:F, 13:147; total samples 286), 140 patients with other chronic liver disease (CLD) (M:F, 75:65; total samples 200), and 28 patients with primary Sjögren's syndrome (all F; total samples 37), were examined for bacteriuria over 6 months by midstream urine (MSU) examination. The overall prevalence of bacteriuria in PBC was 11.2% (7.5% on first MSU), in CLD 12.1% (10.7% on first MSU), 18.4% in the 65 female CLD patients, 10.7% in Sjögren's syndrome patients (3.5% on first MSU). The prevalence of bacteriuria was related to the age of the patient (P less than 0.02) in PBC and to the presence or absence of cirrhosis in both PBC and CLD (P less than 0.02). There was no difference in the prevalence of bacteriuria between PBC and CLD patients taken as a whole or among females alone, cirrhotic or non-cirrhotic groups. In a second prospective study of the cumulative incidence of bacteriuria in PBC versus CLD and Sjögren's no significant differences between groups was observed but among 29 PBC patients the cumulative proportion of positive tests for bacteriuria after 5 months (monthly testing) was 34%. We conclude that there is no specific association between PBC and bacteriuria compared with the prevalence of bacteriuria in other CLD.