[Coagulation abnormalities after total hip prosthesis (THP), a rare cause: antibiotic prophylaxis].

A 87-year-old patient developed coagulation abnormality following hip surgery related to the prophylactic use of cefamandole. Cefamandole as others cephalosporins with a methyl-tetrazol-thiol lateral chain interferes with the vitamin K regeneration cycle as do oral anticoagulants. Therefore, the use of others antibiotics or systematic vitamin K1 supplementation or single dose of cefamandole is recommended for patients with renal failure or with malnutrition. Vitamin K1 supplementation is a simple method resulting in complete resolution of the coagulation disorder.