Difficult diagnosis of tetanus in a sedated patient after ileal resection.

Background: We report a case of tetanus developed after inguinal hernia repair without traumatic wounds, which was difficult to be diagnosed under sedation with mechanical ventilation for pneumonia and anaphylactic shock.

Case presentation: The 67-year-old Japanese male underwent inguinal hernia repair with ileal resection. On postoperative day (POD) 9, he was admitted to the ICU due to dyspnea and worsening oxygenation. Immediately after tazobactam piperacillin was administered as empiric treatment for aspiration pneumonia, anaphylaxis developed, requiring tracheal intubation and continuous intravenous adrenaline. On POD 10, sedative titration increased his extremities' muscle rigidity; weaning from mechanical ventilation was difficult, while he could communicate. On POD 15, tetanus was diagnosed based on the physical examination findings prior to ICU admission.

Conclusion: Tetanus should be considered when patients show abnormal hypertension and no impaired consciousness during muscle rigidity, even in the absence of obvious trauma.