Chronic Liver Disease, Not Everything Is What It Seems: Autoimmune Hepatitis/Primary Biliary Cholangitis Overlap Syndrome.

Overlap syndrome (OS) is a rare condition that shares characteristics of at least two other recognized diseases, whose early diagnosis impacts treatment decisions and prognosis since the unfavorable course of the OS seems to be worse than that of the diseases alone. OS in autoimmune liver diseases combines characteristic features of autoimmune hepatitis (AIH), primary biliary cholangitis (PBC), and primary sclerosing cholangitis. AIH is a chronic, inflammatory disease of the liver that occurs predominantly in females. The disease may start as acute hepatitis and progress to chronic liver disease and cirrhosis. PBC is characterized by a T-lymphocyte-mediated attack on small intralobular bile ducts. A continuous assault on the bile duct epithelial cells leads to their gradual destruction and eventual disappearance. The sustained loss of intralobular bile ducts causes the signs and symptoms of cholestasis and eventually may result in cirrhosis and liver failure. With treatment with ursodeoxycholic acid, the majority of patients now have normal life expectancies. The authors report a subtype of OS, i.e., AIH-PBC overlap, characterized by elevated serum transaminases, cholestasis markers, antimitochondrial antibodies (AMAs), and histological findings compatible with AIH, including moderate-to-severe interface hepatitis. The authors present a clinical case referred for internal medicine consultation regarding a 73-year-old woman presenting pancytopenia and increased transaminases, along with weight loss, decreased appetite, and tiredness. Laboratory tests were positive for the following parameters: antinuclear antibody, anti-double-stranded DNA antibody, AMA, anti-glycoprotein-210, and anti-smooth muscle antibody (anti-actin). Computed tomography of the abdomen displayed chronic liver disease and evidence of small perihepatic ascites. The diagnosis was established with a liver biopsy revealing architectural alteration with severe advanced fibrosis, with bridges and parenchymal nodularity, and histological parenchymal changes of progressive chronic liver disease (chronic biliary disease/PBC) in the stage of cirrhosis. With proper treatment, the condition of the patient significantly improved.