What are the common causes of cholestic pruritus?

The three most common causes of cholestic pruritus are primary biliary cirrhosis, cholestasis of pregnancy, and cholestasis from drugs. Pruritus affects virtually 100% of all patients with primary biliary cirrhosis (PBC) and is the initial symptom in 50%. PBC is a disease of unknown etiology characterized by the destruction of small intrahepatic bile ducts by a granulomatous reaction. Approximately 90% of the patients are female. The serum antimitochondrial antibody test against M2, a component of the pyruvate dehydrogenase complex of mitochondrial enzymes, is 88% sensitive and 96% specific for PBC. Treatment is hepatic transplantation, and it completely eliminates the pruritus.

Benign cholestatic jaundice of pregnancy is a frequent cause of pruritus in pregnancy. The pruritus is most severe in the third trimester. The pruritus disappears and elevated liver function tests return to normal after delivery. Pruritus secondary to cholestasis frequently occurs with drug therapy. Common culprits include oral contraceptives, anabolic steroids, cephalosporins, chlorpropamide, cimetidine, erythromycin estolate, gold, nonsteroidal antiinflammatory drugs, nicotinic acid, penicillin, phenothiazine, phenytoin, progestin, and tolbutamide. Removal of the offending drug usually leads to resolution of symptoms. Other causes of cholestatic pruritus include primary sclerosing cholangitis, obstructive choledocholithiasis, carcinoma blocking the biliary tree, or chronic hepatitis C.

Mela M, Mancuso A, Burroughs AK: Review article: pruritus in cholestatic and other liver diseases, Aliment Pharmacol Ther 17:857– 870, 2003.