Abstract
Mycobacterium chelonae is a rare, non-tuberculous mycobacterium that is highly pathogenic in immunosuppressed patients. Herein, we describe a chronic presentation of cellulitis which was later biopsy-proven as M. chelonae in a lung transplant recipient.
A 61-year-old female bilateral lung transplant recipient presented 15-months post-transplant with multiple erythematous cutaneous lesions of the right arm. She had a 3-month history of waxing and waning cutaneous lesions that had not fully cleared despite antibiotic therapy. The first transplant year was eventful with two episodes of acute cellular rejection necessitating high-dose corticotherapy. Dermatological biopsy performed in a prior visit demonstrated features consistent with dermatitis. Autoimmune etiologies were ruled out, and the patient reported no history of trauma or other nidus of entry for infection. At the time of the current presentation, we observed nodular changes to the cutaneous lesions, which necessitated repeat biopsy, revealing granulomatous infiltrate (Figure 1). Acid-fast staining was positive, and M. chelonae was properly identified. Given her immunosuppressed state, the patient was started on multidrug antibiotic therapy, guided by antibiogram. Skin showed some improvement on observation, however, one large, nodular cutaneous lesion persisted. Decision was made to perform excision in effort to reduce bacterial growth burden. Subsequent biopsy findings were negative, likely a result of immunological phenomenon. She ultimately finished multidrug treatment with complete resolution of skin nodules.
This case underlines the role of corticotherapy and immunosuppression as a major risk factor for atypical infections, such as M. chelonae, in lung transplant recipients. Eradication can be difficult as demonstrated, and thus early recognition and multidrug antibiotic therapy are the cornerstone for management in this population.