Lower Extremity Salvage in a Diabetic Patient With Cutaneous Mucormycosis and COVID-19 After Open Patella Fracture

Background: Cutaneous mucormycosis, while less common than sinonasal or pulmonary infections, can cause widespread tissue necrosis after seemingly innocuous encounters. The most common location of cutaneous mucormycosis is the extremities, and extensive infection has been reported after trauma or orthopedic procedures. Case Report: A 60-year-old female with poorly controlled type 2 diabetes mellitus sustained an open patella fracture after a fall. She underwent washout and internal fixation with cannulated screws and cable tension band wiring. The patient's recovery was complicated by asymptomatic coronavirus disease 2019 (COVID-19) infection and repeated wound dehiscence, with growth of Mucor species initially presumed to be a contaminant. Despite serial washout and debridement, repeat dehiscence and patella exposure were noted. Free tissue transfer to the genicular vessels was selected for coverage of the extensor tendon, patella, and fracture line. In repeat skin cultures, Mucor indicus and Staphylococcus epidermidis grew from the wound. Topical voriconazole and a 6-week course of intravenous isavuconazole and oral doxycycline were started when the Mucor cultures were identified. Conclusion: This case highlights an approach to an indolent mucormycosis infection in the skin over a patella fracture in a patient with poorly controlled diabetes mellitus, including the sequence of surgical care, debridement, and selection of antimicrobials. Major amputation and orthopedic revision were avoided. This patient also underwent successful free tissue transfer after testing positive for COVID-19.