Abstract

Mycobacterium chelonae is a nontuberculous mycobacterium (NTM) characterized as a rapidly growing mycobacterium. M. chelonae can be seen in immunocompromised patients as a rare cause of chronic disseminated cutaneous infections. This species is ubiquitous in the environment and pathologic infection is often a result of direct inoculation with subsequent hematogenous dissemination. Typically, patients present with subacute to chronic lesions of various morphologies, including abscesses, pustules, papules, granulomas and cellulitis. Although many mycobacterial infections are self-limited in immunocompetent individuals, others may spread to soft tissue and bone, presenting as cutaneous and soft tissue lesions that can clinically mimic crystal arthropathy and other rheumatologic conditions. We present a case of an 84-year-old male who presented with complaints of joint pain, swelling, and skin erythema for approximately 8 months. Upon his initial presentation, he was treated for presumed pseudogout with hydroxychloroquine and prednisone. The patient also received multiple courses of antibiotics for presumed cellulitis. With continual acute on chronic symptomatology, the patient re-presented with persistent swollen joints, pedal edema, and had developed large purpuric/vesicular lesions over bilateral extremities. Clinical concern for vasculitis prompted a skin biopsy which showed numerous acid-fast bacilli on a Fite stain. Subsequent mycobacterial culture confirmed the diagnosis of M. chelonae. Unfortunately, shortly after rendering this diagnosis, the patient expired. This case highlights the paramount importance of skin biopsy in chronic painful lesions not responding to therapy.