Extreme and rapidly reversible prolongation of prothrombin time during cefoperazone/sulbactam therapy in a patient with gastrointestinal dysfunction and parenteral nutrition: a case report

This case report describes a suspected coagulation disorder induced by cefoperazone/sulbactam administered for anti-infective therapy. The coagulopathy may be associated with the inhibition of vitamin K synthesis and utilization caused by cefoperazone/sulbactam. The patient was admitted with severe right thalamic intracerebral hemorrhage complicated by Klebsiella pneumoniae infection and remained on total parenteral nutrition (TPN) due to concomitant gastrointestinal dysfunction. We initiated anti-infective therapy with cefoperazone/sulbactam at a dose of 2 g administered intravenously every 12 h for seven consecutive days. On the eighth day of treatment, the patient developed severe coagulation dysfunction, with prothrombin time (PT) markedly prolonged to 262.9 s. Cefoperazone/sulbactam was immediately discontinued, and vitamin K1 along with plasma transfusion was administered. By the third day after intervention, the patient’s coagulation function significantly improved, and PT returned to normal levels. Causality assessment using the Naranjo Adverse Drug Reaction Probability Scale yielded a score of 7, indicating a probable association between the adverse event and cefoperazone/sulbactam use. This case report emphasizes that cefoperazone/sulbactam may cause extremely severe coagulation dysfunction, manifested as markedly prolonged PT in this patient. Clinicians should remain vigilant for this potential adverse reaction and closely monitor coagulation parameters during treatment.