Final answer:
Primary biliary cirrhosis is an autoimmune disease that causes the destruction of intrahepatic bile ducts, leading to chronic liver disease. The most common initial symptom is severe pruritus, especially at night. The associated antibody is the anti-mitochondrial antibody (AMA).
Step-by-step explanation:
The condition described in the question is primary biliary cirrhosis. It is an autoimmune disease that results in the destruction of intrahepatic bile ducts, leading to cholestasis and chronic liver disease. It is most commonly seen in middle-aged women and has an insidious onset.
The most frequent initial symptom is severe pruritus, especially at night. The specific antibody associated with primary biliary cirrhosis is the anti-mitochondrial antibody (AMA).