Survival after cardiopulmonary arrest due to Capnocytophaga canimorsus sepsis: A case successfully managed using plasma exchange

Capnocytophaga canimorsus sepsis is potentially fatal, even in immunocompetent hosts. This report describes a case involving a 57-year-old woman, who developed fever after a dog bite and initially presented without an evident focus. On the day of admission, she deteriorated to pulseless electrical activity during transport and achieved return of spontaneous circulation after approximately 23 minutes of resuscitation. Broad-spectrum antimicrobials (meropenem) were initiated for septic shock, and Capnocytophaga canimorsus subsequently grew in both the pre-admission and admission blood cultures. Peripheral discoloration suggested purpura fulminans. A precipitous decline in platelet count, schistocytosis, elevated lactate dehydrogenase levels, and acute kidney injury fulfilled the criteria for thrombotic microangiopathy, whereas ADAMTS13 activity was normal. Intensive care consisted of red blood cell and platelet transfusions, continuous hemodiafiltration transitioning to intermittent hemodialysis, mechanical ventilation with tracheostomy, and therapeutic plasma exchange once daily for three sessions. Hematological abnormalities resolved, schistocytes disappeared, organ dysfunction improved, and she was ultimately removed from ventilation and dialysis with full neurological recovery. This report describes survival after cardiopulmonary arrest due to Capnocytophaga canimorsus sepsis and suggests that plasma exchange may be a useful adjunct for secondary thrombotic microangiopathy in this setting. Early diagnosis, prompt antibiotic treatment, and multidisciplinary critical care are essential.