Common autoimmune diseases associated with primary biliary cirrhosis (PBC)
Primary biliary cirrhosis is an autoimmune disease of the liver marked by slow progressive destruction of the small bile ducts.
Bile cholestasis leads to tissue damage with fibrosis and cirrhosis. It is more common in women (9:1). Up to 80% have AMAs.
The most specific AMA is the M2 antibody directed against the E2 subunit of the pyruvate dehydrogenase complex on the inner mitochondrial membrane. Many patients with PBC have one or more additional autoimmune disorders:
• Keratoconjunctivitis sicca (secondary Sjögren’s syndrome): 40% to 60%
• Autoimmune thyroiditis (Hashimoto’s disease): 10% to 15%
• Arthritis: 5% to 10% with classic seropositive rheumatoid arthritis while another 10% may have a seronegative, nonrheumatoid arthritis characterized by a self-limited, symmetric, polyarticular synovitis
• Limited scleroderma occurs in 5% to 15% of PBC patients and antedates PBC by 14 years. Most have anticentromere antibodies.
• Others: Raynaud’s phenomenon, pernicious anemia, celiac disease, IBD, SLE, polymyositis
