Cholestatic drug-induced liver injury (DILI) is the severe form of DILI with a grave outcome.
Drug-metabolizing enzymes play an important role in the metabolism of drugs. The genetic
polymorphism of drug-metabolizing enzymes may influence the activities and expression of
these enzymes and thereby affect the susceptibility and severity of DILI.
UDP-glucuronosyltransferase (UGT) is an important phase 2 detoxification enzyme, which is
related to congenital hyperbilirubinemia. Recently, the genetic polymorphism of UGT1A1 was
reported to be associated with jaundice induced by some drugs, and UGT1A7 was shown to be
related to the susceptibility of hepatocellular carcinoma and other cancers. Ursodeoxycholic
acid (UDCA ) is a hydrophilic bile acid that is increasingly used for the treatment of
various cholestatic disorders. The aims of this study are (1) to assess the association of
the genetic polymorphism of UGT1A1 and 1A7, and the susceptibility and severity of
drug-induced liver injury (DILI), with emphasis on the cholestatic DILI; (2) to evaluate the
treatment effect of UDCA in the DILI, with special reference to the cholestatic
hepatotoxicity.