PBC

Primary biliary cholangitis (PBC) is a chronic autoimmune liver disease characterized by progressive destruction of the small intrahepatic bile ducts, leading to cholestasis and, over time, fibrosis and cirrhosis if untreated. In 2015 the name was changed from primary biliary cirrhosis to primary biliary cholangitis to reflect its pathophysiology and to avoid stigma associated with cirrhosis.

Most patients are middle-aged women, and prevalence varies by region. PBC is considered autoimmune in nature, with genetic predisposition and environmental triggers, and it often coexists with other autoimmune disorders such as thyroiditis, Sjögren syndrome, or celiac disease.

Pathophysiology involves autoimmune-mediated injury to small bile ducts within the liver, resulting in impaired bile flow, cholestasis, and progressive destruction of the ducts. The exact cause is unknown, but associations with HLA alleles and specific autoantibodies support an immune basis.

Symptoms commonly include fatigue and pruritus. Jaundice, right upper quadrant discomfort, and signs of advanced liver disease (edema, ascites) may occur later.

Diagnosis relies on a cholestatic liver enzyme pattern—elevated alkaline phosphatase and gamma-glutamyl transferase—plus serology. Antimitochondrial antibodies are positive in about 90–95% of cases. If AMA is negative, correlation with elevated cholestasis markers and liver biopsy can confirm diagnosis, especially when other causes are excluded; imaging is used to rule out biliary obstruction or other hepatic diseases.

Treatment centers on ursodeoxycholic acid (UDCA) at about 13–15 mg/kg/day as first-line therapy, which can slow disease progression in many patients. Obeticholic acid is approved for certain patients with an inadequate response to UDCA. Additional measures include management of pruritus and fat-soluble vitamin supplementation; treatment of complications (ascites, varices). Liver transplantation is considered for end-stage disease or liver failure. Prognosis varies with stage at diagnosis and biochemical response; many patients have normal life expectancy with appropriate management.