Abstract <p>This case report describes a patient who survived toxic shock syndrome caused by <i>Paeniclostridium sordellii</i> after elective gynaecological surgery. Toxic shock syndrome due to <i>P. sordellii</i> carries a high risk of mortality, and only a few case reports of survivors due to gynaecological and obstetric infections with <i>P. sordellii</i> exist.</p> Case Presentation <p>A 49-year-old woman presented at the emergency department three days after an elective gynaecological surgery with lower abdominal pain, nausea, vomiting, and syncope tendencies. She was afebrile, had leucocytosis, and significant haemoconcentration. A gynaecological examination revealed normal postoperative findings except for minor ecchymosis on the vulvae. A computed tomography of the abdomen and pelvis demonstrated significant extravascular fluid accumulation. Within hours, she developed haemodynamic shock. Infection due to <i>P. sordellii</i> was suspected and antibiotics were initiated, and hysterectomy performed before <i>P. sordellii</i> was identified. During the first eight days, several drains were inserted due to fluid accumulation. To compensate for the massive capillary leakage, 107 L of fluid were administered intravenously, guided by Pulse index Contour Continuous Cardiac Output (PiCCO) and repeated transthoracic echocardiography. After the first eight days, the patient was stabilised and she was discharged to a rehabilitation institution after an eight-week hospital stay.</p> Conclusion <p>Toxic shock syndrome caused by <i>P. sordellii</i> should be suspected in a patient with rapidly developing haemodynamic shock with massive capillary leakage in combination with profound leucocytosis. Awareness of this condition is vital, since early recognition, antibiotics, aggressive surgical intervention, and optimised intensive care management are essential to avoid a fatal outcome.</p>