What underlying issue does primary biliary cirrhosis primarily affect?

Primary biliary cirrhosis, now more commonly referred to as primary biliary cholangitis, primarily affects the liver. It is an autoimmune disease that leads to the progressive destruction of the small bile ducts within the liver. This destruction results in cholestasis, which is the impairment of bile flow and accumulation of bile acids in the liver. Over time, this process causes damage to hepatocytes, leading to liver inflammation, fibrosis, and eventually cirrhosis.

The disease is characterized by the presence of specific autoimmune antibodies, such as anti-mitochondrial antibodies (AMA). The liver's inability to secrete bile into the intestine not only affects digestion but also contributes to systemic effects, including fatigue and pruritus (itching). As the disease progresses, patients may develop symptoms related to liver failure, such as jaundice, ascites, and hepatic encephalopathy.

While other systems such as the kidneys, skin, and joints may sometimes be involved due to associated autoimmune conditions or secondary effects of liver disease, the primary target of primary biliary cholangitis is unequivocally the liver itself. This distinction is vital for diagnosis and management of the disease.