A 52-year-old woman comes to the office due to intense itching and fatigue. She is unable to specify when her symptoms started as they developed gradually. Past medical history is significant for hypothyroidism and carpal tunnel syndrome. Current medications include levothyroxine. The patient lives with her husband and 3 children. She does not smoke and drinks wine on social occasions. Vital signs are normal. Cardiopulmonary examination shows no abnormalities. The abdomen is soft with normal bowel sounds. Hepatomegaly is present. There is no scleral icterus or jaundice, but bilateral xanthelasma and skin excoriations are evident. Laboratory results are as follows:
Serum creatinine 1.0 mg/dL Total cholesterol 503 mg/dL Total bilirubin 1.5 mg/dL Alkaline phosphatase 410 U/L Aspartate aminotransferase (AST, SGOT) 42 U/L Alanine aminotransferase (ALT, SGPT) 44 U/L
A right upper quadrant ultrasound shows a normal common bile duct. Which of the following is the most appropriate next step in management of this patient?
This patient has several features of cholestasis (impaired biliary flow), including fatigue, pruritus, and elevated alkaline phosphatase. A right upper quadrant ultrasound distinguishes intrahepatic (no biliary tract dilation) from extrahepatic (biliary tract dilation; eg, due to gallstones) cholestasis. If ultrasound suggests intrahepatic cholestasis (as with this patient), the next step is to obtain serum anti-mitochondrial antibody titers, which have high sensitivity and specificity for primary biliary cholangitis (PBC, previously termed primary biliary cirrhosis).
PBC is a chronic liver disease characterized by autoimmune destruction of the intrahepatic bile ducts with resulting cholestasis. It presents most commonly in middle-aged women and is insidious in onset. As the disease progresses, jaundice, hepatomegaly, steatorrhea, and portal hypertension may develop. Additional complications can include severe hyperlipidemia (with xanthelasma) and metabolic bone disease. PBC is often associated with other autoimmune disorders (eg, autoimmune thyroid disease).
(Choices B and E) Autoimmune hepatitis is associated with elevated titers of antinuclear antibodies and anti-smooth muscle antibodies. It is characterized by fluctuating hepatocellular injury (ie, elevated transaminases) rather than cholestasis. First-line treatment includes oral glucocorticoids.
(Choice C) A number of medications can cause intrahepatic cholestasis, including certain antibiotics (eg, macrolides), anabolic steroids, and oral contraceptives. Levothyroxine is not associated with cholestasis.
(Choice D) Abdominal MRI is primarily used to evaluate abdominal masses or clarify nonspecific abnormalities on other imaging tests. It is not needed in the evaluation of PBC.
Educational objective:
Primary biliary cholangitis (previously termed primary biliary cirrhosis) is a chronic liver disease characterized by intrahepatic cholestasis due to autoimmune destruction of small bile ducts. It presents in middle-aged women with fatigue, pruritus, hepatomegaly, and elevated alkaline phosphatase. The diagnosis is confirmed with serum anti-mitochondrial antibody titers.