Purpura Fulminans from Capnocytophaga canimorsus in an Immunocompromised Host

Abstract

Introduction: Purpura fulminans is a rare but fatal manifestation of Capnocytophaga canimorsus bacteremia that can present in immunocompromised hosts. This can have a profound impact on patients, including recipients of allogeneic hematopoietic stem cell transplant. Despite aggressive therapy, mortality can be as high as 60% and most patients require amputation of multiple extremities. Case Presentation: We present a 31-year-old woman s/p myeloablative allogeneic transplant, presenting with purpura fulminans and septic shock. She had been on Immunosuppressive therapy with rituximab and tacrolimus. Despite aggressive antibiotic coverage and supportive therapy, although her shock was resuscitated, she had to undergo bilateral below-knee amputations. Discussion: We attempt to highlight the clinical presentation, pathophysiology and potential therapeutic options for immunocompromised patients presenting with septic shock from C. canimorsus. The importance of pre-transplant counselling on handling and adoption of new pets to prevent zoonotic infections is also discussed. Early recognition and initiation of antibiotics play a crucial role to reduce mortality in patients receiving HSCT.

Keywords

• purpura fulminans
• capnocytophaga canimorsus
• stem cell transplant
• chronic graft-versus-host disease