Cutaneous infection with rapidly-growing mycobacterial infection following heart transplant: a case report and review of the literature.

Nontuberculous mycobacteria are ubiquitous and infrequently cause disease in humans, most commonly in immunocompromised hosts. One type of nontuberculous mycobacteria is Mycobacterium abscessus. This rapidly growing mycobacterium is a soil or water saprophyte. It was previously classified as a subspecies of Mycobacterium chelonae; however, current taxonomy now designates it as a separate species. Rapidly growing mycobacteria are resistant to the usual antituberculous drugs. This emphasizes the need for tissue diagnosis and obtaining specimens for culture and drug susceptibility testing. M abscessus has been reported to cause infection in renal transplant patients, but is less well described in cardiac transplant recipients. We report the case of a 65-year-old man who presented 5 years after transplantation for heart failure, with a 2-day history of progressive right lower extremity swelling and redness. He recalled no antecedent trauma and denied any unusual epidemiologic exposure. Medical history included diabetes with peripheral neuropathy and renal insufficiency, hypertension, and right-sided heart failure felt to be due to obstructive sleep apnea. A punch biopsy of the area grew M abscessus sensitive only to clarithromycin (MIC not reported), amikacin (30 microg/mL), and kanamycin (30 microg/mL). On subsequent clinic visits, the patient had decreased leg swelling and resolution of the papular lesions. Ten weeks into antimycobacterial therapy, the patient had an increase in creatinine to 4.9 mg/dL from a baseline of 2.0 with fluid overload necessitating discontinuation of aminoglycoside therapy. He completed 6 months of treatment with oral clarithromycin. We describe these findings and review the literature in this report.