title: Severe INR elevation in a patient with choledocholithiasis receiving cefoperazone.
abstract: Cefoperazone is a third-generation cefalosporin that contains the N-methyl- thio-tetrazole (NMTT) side chain, which inhibits vitamin K-dependent carboxylation. Administration of NMTT-containing cefalosporins can cause alterations in the hepatic glutathione redox state, resulting in a dose-related increase in oxidised glutathione, which is responsible for the inhibition of microsomal reduction of vitamin K epoxide. In addition, cefoperazone is not metabolised and is excreted predominantly through the bile. In patients with hepatic impairment, the clearance of cefoperazone has been shown to be significantly reduced and the half-life prolonged. We report a case of choledocholithiasis related to a prolonged prothrombin time and INR secondary to cefoperazone therapy.
authors.affiliation: Department of Internal Medicine, Division of Gastroenterology, Medical Faculty of Gazi University, Ankara, Turkey. hakanalagoz@gazi.edu.tr
authors.forename: Hakan
authors.initials: H
authors.lastname: Alagozlu
authors.forename: Mehmet
authors.initials: M
authors.lastname: Cindoruk
authors.forename: Selahattin
authors.initials: S
authors.lastname: Unal
mesh_terms: D000368:Aged; D000900:Anti-Bacterial Agents / Q000009:adverse effects / Q000627:therapeutic use; D002438:Cefoperazone / Q000009:adverse effects* / Q000627:therapeutic use; D042883:Choledocholithiasis / Q000097:blood / Q000139:chemically induced* / Q000175:diagnosis; D005260:Female; D006801:Humans; D007020:Hypoprothrombinemias / Q000097:blood / Q000139:chemically induced / Q000175:diagnosis; D019934:International Normalized Ratio; D011517:Prothrombin Time
chemical_list: D000900:Anti-Bacterial Agents; D002438:Cefoperazone