Primary Biliary Cholangitis (PBC)
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Overview
Plain-Language Overview
Primary Biliary Cholangitis (PBC) is a chronic disease that affects the liver, specifically the small bile ducts inside it. These bile ducts help carry bile, a fluid important for digestion, from the liver to the intestines. In PBC, the body's immune system mistakenly attacks these ducts, causing inflammation and damage. Over time, this damage can block bile flow, leading to a buildup of bile in the liver. This buildup can cause symptoms like fatigue, itching, and jaundice (yellowing of the skin and eyes). If untreated, PBC can progress to liver scarring (cirrhosis) and liver failure. The disease mainly affects middle-aged women and is considered an autoimmune condition.
Clinical Definition
Primary Biliary Cholangitis (PBC) is a chronic autoimmune cholestatic liver disease characterized by immune-mediated destruction of the small intrahepatic bile ducts. The hallmark pathology is nonsuppurative granulomatous inflammation leading to progressive bile duct loss and cholestasis. The exact cause is unknown but involves a combination of genetic predisposition and environmental triggers resulting in loss of immune tolerance to mitochondrial antigens, especially the E2 subunit of the pyruvate dehydrogenase complex (PDC-E2). Clinically, PBC presents with cholestatic liver enzyme abnormalities (elevated alkaline phosphatase), pruritus, and fatigue. If untreated, it can progress to fibrosis, cirrhosis, and end-stage liver disease. PBC predominantly affects middle-aged women and is associated with other autoimmune diseases such as Sjögren syndrome and autoimmune thyroiditis.