Prosthetic Knee Joint Infection by Mycobacterium fortuitum

Nontuberculous mycobacteria (NTM) are environmental mycobacteria found in water, soil, and dust. They usually cause opportunistic infections in humans and animals. The incidence of NTM infections has risen globally, affecting both immunocompromised and immunocompetent individuals. Mycobacterium fortuitum , a rapidly growing NTM species, is primarily associated with skin, soft tissue, postoperative wound infections, as well as catheter-related or implant-related infections. It is rarely implicated in pulmonary or disseminated disease. Prosthetic joint infections caused by M. fortuitum have a slow onset, and diagnosis is often delayed as the awareness among clinicians is low, which can lead to joint destruction and functional impairment. Management typically involves 2 drug regimens based on susceptibility testing, with commonly effective agents including fluoroquinolones, doxycycline, amikacin, and sulfonamides, as per the American Thoracic Society (ATS)/Infectious Diseases Society of America (IDSA) 2007 Guidelines. Surgical debridement and removal of the implant may be required for relief of symptoms.