Severe delayed coagulopathy caused by cefoperazone/sulbactam: A case report.

This case report described a suspected severe coagulopathy attributed to cefoperazone/sulbactam, and this adverse reaction might be associated with the inhibition of the vitamin K cycle by cefoperazone/sulbactam, leading to vitamin K deficiency within the body. We reported a patient diagnosed with bacterial pneumonia, who received cefoperazone/sulbactam during hospitalization. The patient was administered cefoperazone/sulbactam via intravenous infusion at a dose of 1.5 g every 8 h for a consecutive treatment period of 23 days. On the 26th day, the patient developed a serious adverse reaction characterized by prolonged clotting time. After treatment with vitamin K1, the coagulation parameters significantly improved by the 28th day (prothrombin time decreased by 88.4%, activated partial thromboplastin time decreased by 61.1%, and international normalized ratio decreased by 88.5%). The Naranjo assessment score was 5, suggesting that the patient's coagulation disorder could be related to the use of cefoperazone/sulbactam. This report highlights that patients at high risk of bleeding should be vigilant about the coagulopathy caused by cefoperazone/sulbactam- and extend the duration of coagulopathy monitoring.