Case Report: Cutaneous Mycobacterium chelonae infection in a kidney transplant recipient with long-term immunosuppression and eculizumab therapy.

Mycobacterium chelonae is a rapidly growing non-tuberculous mycobacterium (NTM) that causes skin and soft tissue infections, particularly in immunocompromised patients. We present the case of a 51-year-old woman receiving eculizumab therapy after kidney transplantation, who developed painful nodules and ulcers on the lower leg. Standard laboratory and imaging findings were unremarkable. Initial cultures were negative, but biopsy and subsequent wound cultures identified M. chelonae. Repeat testing confirmed the pathogen. The patient was successfully treated with a 12-month course of combination antibiotics, including clarithromycin, linezolid, and doxycycline, along with intralesional gentamicin. A follow-up biopsy showed dermal fibrosis without microorganisms. This case highlights the diagnostic challenges of M. chelonae in transplant recipients and emphasizes the importance of molecular diagnostics and tailored therapy. To the best of our knowledge, this is the first reported case of M. chelonae infection in a kidney transplant recipient receiving eculizumab as part of her post-transplant management.