1419. A Rare Case of Clostridium beijerinckii Traumatic Osteomyelitis

BACKGROUND: We present a case of Clostridium beijerinckii osteomyelitis in the presence of retained foreign bodies not seen on MRI. METHODS: A 45-year-old female with type 2 diabetes sustained multiple open right leg injuries, grossly contaminated with gravel, after a motor vehicle collision. She underwent external fixation (ex-fix) and 5 irrigations and debridements (I&D) initially. Polymicrobial intraoperative cultures (Cx) were treated with vancomycin and ertapenem for 6 weeks. One month post-antibiotic completion, pain, and swelling developed in ankle; contrast MRI revealed avascular necrosis and osteomyelitis (OM) of talus. Cx from repeat I&D grew same organisms; meropenem was recommended for 6 weeks. During meropenem week 6, pain was minimal and wound was closed. During attempt to implant hardware, pus was seen around peroneal tendon. Cx grew Clostridium species and Bacteroides from tibia, calcaneus, talus, and peroneal tendon sheath; meropenem was continued. Pain worsened 3 weeks later; I&D revealed pus in lateral ankle. To better access the medial ankle, a longitudinal incision was made along posterior tibial tendon, perpendicular to prior surgical incision. Immediate purulence, grass blades, and rocks were seen. Brucella agar had a rare gray colony at 48 hours and was subbed to blood and Brucella agar; it grew on Brucella agar with aero tolerance test. Gram stain showed Gram-positive rods with subterminal spores. Rapid ANA panel identified isolate as Clostridium beijerinckii (Cb) with > 99.9% probability and bioscore 1/24. RESULTS: Cb is a strict anaerobic gram-positive rod with oval subterminal spores. Found in soil and water, its main use is industrial solvent production. Infection by Cb is rare; only 2 cases of OM, 1 traumatic endophthalmitis, and 1 mitral valve endocarditis have been reported. While uncommon, Clostridial osteomyelitis is associated with contaminated open traumatic injuries. It can be difficult to eradicate, despite aggressive surgical intervention and appropriate antibiotics. CONCLUSION: This is the third case of Cb OM described. Anaerobic cultures should be collected during I&D of open traumatic wounds. If infection persists, careful intraoperative evaluation of wound for residual foreign bodies, even if not seen radiologically, should be performed. [Image: see text] [Image: see text] DISCLOSURES: All authors: No reported disclosures.