Definition of Primary biliary cirrhosis (PBC)

Primary biliary cirrhosis (PBC): A liver disease caused by an abnormality of the immune system. Small bile ducts within the liver become inflamed and obliterated. Backup of bile causes intense skin itching and yellowing of the skin (jaundice). Lack of bile decreases absorption of calcium and vitamin D, leading to osteoporosis. Cirrhosis (scarring of the liver) develops over time.