The development of sclerosing cholangitis (SC) is observed in up to 50% of children followed up for autoimmune hepatitis (AIH). In adults, the prevalence is less known, although a recent study found evidence of SC in 10% of AIH patients using magnetic resonance cholangiopancreatography (MRCP). The aim of this study was to assess prospectively the prevalence of SC in adults with AIH. Fifty-nine consecutive patients with AIH diagnosed according to International Autoimmune Hepatitis Group score (women, 71%; mean age, 48 years; cirrhosis, 23%) underwent both MRCP and percutaneous liver biopsy. Twenty-seven patients with cirrhosis of nonbiliary or non-autoimmune etiology served as controls. Fourteen AIH patients (24%) showed mild MRCP abnormalities of intrahepatic bile ducts (IHBDs). None had abnormal common bile duct or convincing evidence of SC on MRCP or biopsy. A diagnosis of overlapping SC was nevertheless retained in one patient with MRCP abnormalities who subsequently developed symptomatic cholestasis despite corticosteroid therapy. Fibrosis score was the only independent parameter associated with bile duct abnormalities on MRCP (odds ratio 2.4; 95% confidence interval 1.4-4.7) and the percentage of patients with IHBD MRCP abnormalities was not different among F3-F4 AIH patients (n ؍ 24) and cirrhotic controls (46% versus 59%; NS). Conclusion: In this cohort of adult patients with AIH, the prevalence of SC was much lower than previously reported (1.7%). Mild MRCP abnormalities of IHBD were seen in a quarter of patients, but these abnormalities resulted from hepatic fibrosis and not SC. In the absence of cholestatic presentation, MRCP screening does not seem justified in adult-onset AIH. (HEPATOLOGY 2009;50:528-537.)