cholestasis

Cholestasis is a condition in which bile formation or bile flow from the liver is impaired, leading to accumulation of bile acids in the liver and in the blood. This disruption can cause a cholestatic pattern of liver injury and symptoms such as jaundice and intense itching.

Cholestasis is categorized as intrahepatic or extrahepatic. Intrahepatic cholestasis results from hepatocellular dysfunction or small bile duct obstruction due to drugs, viral hepatitis, autoimmune diseases (such as primary biliary cholangitis), genetic disorders, or pregnancy-related cholestasis. Extrahepatic cholestasis is caused by obstruction of the bile ducts, often from gallstones, tumors, or strictures.

Common clinical features include yellowing of the skin and eyes (jaundice), dark urine, pale stools, and fatigue. Pruritus is typical. Prolonged cholestasis can lead to fat-soluble vitamin deficiencies (A, D, E, K) and may cause malabsorption and, in severe cases, steatorrhea.

Diagnosis relies on a cholestatic laboratory pattern: elevated alkaline phosphatase and gamma-glutamyl transferase, with conjugated (direct) hyperbilirubinemia. Transaminases may be only mildly elevated. Imaging such as ultrasound and MRCP helps identify obstruction; ERCP may be used for therapy. Liver biopsy is reserved for uncertain cases or to define specific etiologies.

Management targets the underlying cause and symptom relief. Ursodeoxycholic acid is commonly used in many cholestatic disorders. Pruritus can be treated with cholestyramine, rifampin, or other agents. Adequate fat-soluble vitamin supplementation and dietary adjustments are advised. Prognosis varies with the underlying disease; some forms progress to cirrhosis, while others resolve with treatment.