An unusual case of Mycobacterium chelonae infection

Introduction: A 32 year old lady developed multiple distinct, purple, raised, itchy lesions on her limbs, during a prolonged hospital admission. The lesions developed over six to eight weeks with no evidence of improvement. One lesion was biopsied and sent for analysis.

The patient had a background of end stage renal failure from Anti-glomerular basement membrane (Anti-GBM) disease and she went on to receive a renal transplant. Eleven months prior to her hospital admission her transplant failed from de-novo focal segmental glomerulosclerosis. She had been admitted for 9 months with an eating disorder and malnutrition. She had been off any immunosuppressive agents for 6 months at the time that the lesions appeared.

Methods: The lesion biopsied was consistent with a dermal abscess. The Ziehl-Neelsen stain was negative but a mycobacterium was cultured. This was confirmed to be Mycobacterium chelonae on reference lab testing (sensitivities awaited). She had no other lesions of concern on imaging.

Results:Due to the disseminated nature of the lesions she was started on a 2 week course of intravenous amikacin with oral azithromycin and levofloxacin; the oral components to be continued for 2 to 6 months dependent on clinical response.

Discussion:Mycobacterium chelonae is a nontuberculous mycobacterium abundant throughout the environment. It commonly causes skin lesions or cellulitis as well respiratory disease and urinary catheter colonization. It is a less common Rapidly Growing Mycobacterium (RGM) which usually occurs in patients on immunosuppression. The immunosuppressed state in this case was that caused by dialysis and malnutrition.