Overlap syndrome of primary biliary cholangitis and primary sclerosing cholangitis: two case reports

BACKGROUND: Overlap syndrome between primary biliary cholangitis and primary sclerosing cholangitis is an extremely rare condition that has been reported in only few published cases so far in the literature. We highlight here the rarity of this condition and indicate the importance of its recognition. CASE PRESENTATION: We report two cases showing the manifestations of both primary biliary cholangitis and primary sclerosing cholangitis in two Tunisian female patients aged 74 and 42 years, respectively. The first case is a woman who was initially diagnosed with decompensated cirrhosis. Magnetic resonance cholangiopancreatography showed multiple strictures of the common bile duct, and histological findings led to the diagnosis of primary biliary cholangitis/primary sclerosing cholangitis. She was successfully treated with ursodeoxycholic acid. The second case is a middle-aged woman, suffering from primary biliary cholangitis and who was treated with ursodeoxycholic acid. At her 12 month follow-up appointment, she presented with a partial clinical and biochemical response. Tests showed normal thyroid function, liver autoimmune tests for autoimmune hepatitis were negative, and celiac disease markers were also negative. The diagnosis of overlap syndrome of primary biliary cholangitis/primary sclerosing cholangitis was finally made on the results of magnetic resonance cholangiopancreatography that showed multiple strictures of the common as well as intrahepatic bile ducts. The patient was put on ursodeoxycholic acid at a higher dose. CONCLUSIONS: Our cases raise awareness for this rare condition and indicate the importance of recognizing a possible overlap syndrome, especially in patients with primary biliary cholangitis, to optimize treatment. We suggest considering the overlap syndrome of primary biliary cholangitis/primary sclerosing cholangitis when a patient presents with the diagnostic criteria of both diseases.