Overlap Syndrome of Autoimmune Hepatitis and Primary Biliary Cirrhosis: A Clinical Enigma

Abstract

“Overlap syndrome” is a term used to describe variant forms of autoimmune hepatitis (AIH) which present with characteristics of AIH and primary biliary cirrhosis (PBC) or primary sclerosing cholangitis (PSC). Patients with overlap syndrome present with both hepatitic and cholestatic serum liver test and the clinical, biochemical, and histological features of these autoimmune diseases are overlapped. Thus, it is difficult to appreciate overlap syndrome as an actual diagnostic entity. AIH-PBC is the most common form of overlap syndrome, affecting almost 10% of adults with AIH or PBC. Transitions from PBC to AIH-PBC overlap syndrome have also been reported. Ursodeoxycholic acid is usually combined with immunosuppressive therapy but end-stage disease requires liver transplantation. We present a case of Overlap Syndrome (AIHPBC) in a 16 year old girl who presented to us with features of obstructive jaundice. She had six months history of generalised itching, yellow discoloration of skin and urine, decreased appetite and intermittent abdominal pain. Liver function test revealed conjugated hyperbilirubinemia, with moderate elevation of liver enzymes. Antinuclear, anti-muscle M2 and anti-glycoprotein 210 antibodies were positive. Liver biopsy showed features of primary biliary cirrhosis. The patient responded to ursodeoxycholic acid and immunosuppression.