Isolated granulomatous hepatitis-A histopathological surprise mimicking cholangiocarcinoma in ulcerative colitis.

A 63-yr-old woman, known case of ulcerative colitis, was diagnosed with sclerosing cholangitis 2 years back. She was admitted for investigation of abdominal discomfort, fatigue with elevated alkaline phosphatase and deranged liver function test. Imaging studies (computerised tomography and magnetic resonance imaging) demonstrated a normal biliary tree with focal hepatic lesion which was showing features of cholangiocarcinoma. Ultrasound guided biopsy of the lesion surprisingly revealed non caseating granulomata. Granulomatous hepatitis occurs in less than 1 percent of cases of inflammatory bowel disease. A clinical diagnosis of isolated granulomatous hepatitis was established as the lesion remained stable on follow up and no other cause for it was identified on further investigation. Although the differential diagnosis of focal hepatic lesion in patients with ulcerative colitis with sclerosing cholangitis is wide, granulomatous hepatitis presenting as focal mass lesion mimicking cholangiocarcinoma has never been described previously.