Fusobacterium emphysematous pyomyositis with necrotizing fasciitis of the leg presenting as compartment syndrome: a case report

BACKGROUND Fusobacterium necrophorum is a common agent of disease in humans, but the occurrence of primary infections outside the head and neck area is extremely rare. While infection with Fusobacterium necrophorum has a rather benign course above the thorax, the organism is capable of producing very severe disease when located in unusual sites, including various forms of septic thrombophlebitis. No infections of the leg have been documented before; thus, antibiotic coverage for Fusobacterium is currently not recommended in this area. CASE PRESENTATION A 50-year-old homeless African-American man presented complaining of severe pain in his right lower extremity. A clinical workup was consistent with emphysematous pyomyositis and compartment syndrome; he received limb-saving surgical intervention. The offending organism was identified as Fusobacterium necrophorum, and the antibiotic coverage was adjusted accordingly. CONCLUSIONS Bacteria typically involved in necrotizing infections of the lower extremity include Group A ß-hemolytic Streptococcus, Clostridium perfringens, and common anaerobic bacteria (Bacteroides, Peptococcus, and Peptostreptococcus). This case report presents a case of gas gangrene of the leg caused by Fusobacterium necrophorum, the first such case reported. Fusobacterium should now be included in the differential diagnosis of necrotizing fasciitis of the extremities.