Distant myonecrosis by atraumatic Clostridium septicum infection in a patient with metastatic breast cancer

Abstract

Clostridium septicum is an anaerobic, gram-positive bacillus known to cause myonecrosis, also known as gas gangrene, a life-threatening necrotizing soft tissue infection. Though it accounts for just 1 % of all infections attributable to Clostridia spp., C. septicum is a highly virulent and aggressive pathogen. Classic presentations of infection include bacteremia resulting in shock, myonecrosis, and vascular seeding. C. septicum-associated gas gangrene most commonly occurs in the setting of traumatic injury, but has also been reported in patients with colorectal malignancy, immunosuppression, neutropenia, and exceedingly rare in association with breast cancer. We report the case of a 56-year-old female patient with stage IV mixed lobar and ductal breast carcinoma with metastasis to the bone and liver, who presented with spontaneous C. septicum myonecrosis of the right hand. No prior traumatic injury was noted. Following amputation of the right forearm, antibiotic treatment, and multiorgan support, the patient passed following transition to palliative care. We hope to increase awareness of this relatively uncommon, though potentially deadly pathogen, as well as to discuss treatment options in patients infected with C. septicum.

Keywords: Atraumatic myonecrosis; Breast cancer; Clostridium septicum.

Fig. 1

A–B. Computed Tomography Angiogram of Right Upper Extremity upon ED arrival. Imaging showed patent radial, palmar arch, and ulnar artery without stenosis. Extensive subcutaneous, intramuscular, and vascular emphysema along with soft tissue edema was found throughout the hand, suggestive of myonecrosis. Gas was most prominently visualized along the dorsal and ventral aspects of the metacarpals of the (A) wrist and (B) hand. C. Physical exam finding on Day 6. Extensive ecchymosis, bullae, and dusky mottling on extremities. D. Preoperative Photos. Visual characteristics along with imaging were suggestive that below elbow amputation would sufficiently provide margins clear of infection for source control.