Case Presentation: A 58-year-old man from Thailand presented to the emergency department with a one month history of night sweats, penile pain, swelling, and scrotal wound drainage. Five months prior, he had traveled to India for a semi-rigid penile implant. After a diagnosis of “urethral tuberculosis” in Thailand, he began RIPE therapy (rifampin, isoniazid/pyridoxine, pyrazinamide, ethambutol) but showed no improvement and returned to the U.S. for further evaluation.Initial vitals showed a heart rate of 120 beats/min with atrial fibrillation and systolic blood pressure of 195 mmHg. On examination, he had diffuse scrotal edema, penile discharge, and a 1 cm midline scrotal wound. Labs showed leukocytosis (13,300/µL, 74% neutrophils), and scrotal ultrasound raised concern for pyocele. He was started on piperacillin-tazobactam and continued on RIPE therapy. Infectious disease and urology consultations were obtained. Cultures from the wound exudate grew enterococcus faecalis and acid-fast bacilli, with a negative mycobacterium tuberculosis PCR. RIPE therapy was discontinued. The patient underwent explantation of the prosthesis with wound washout; intraoperative findings included gross purulence, a urethrocorporal fistula, and necrotic tissue.Cultures speciated mycobacterium abscessus within a week. Therapy was adjusted to azithromycin, amikacin, imipenem-cilastatin, and tigecycline. This regimen was complicated by acute kidney injury and QT prolongation, leading to the discontinuation of amikacin and azithromycin. Recurrent nausea and vomiting, likely due to tigecycline, caused severe dehydration. Susceptibility testing identified macrolide resistance (ERM gene detected), prompting consultation with a mycobacteria expert who advised imipenem, omadacycline, and linezolid. Due to omadacycline’s high cost, Tigecycline was continued. The patient was discharged but faced readmissions for wound dehiscence and antimicrobial-related side effects.
Discussion: Nontuberculous mycobacterias (NTMs) are environmental pathogens that cause a spectrum of infections, including pulmonary, skin and soft tissue, and notoriously prosthetic device infections. NTMs are categorized by growth rate; rapid-growing species (e.g., M. abscessus, M. fortuitum, M. chelonae) typically grow within seven days and are often associated with device-related infections. Managing M. abscessus infections is challenging, particularly in macrolide-resistant cases. For macrolide-susceptible strains, combination therapy with azithromycin, amikacin, and omadacycline is recommended. In resistant cases, intravenous amikacin, with three additional agents, one of which is intravenous (imipenem preferred); is recommended. Linezolid, omadacycline or tigecylcine, and clofazimine are some alternatives. Given drug toxicities, multidrug therapy for NTM prosthetic infections requires careful monitoring.
Conclusions: This case highlights the complexities in managing M. abscessus infections, especially with macrolide resistance, which limits effective treatment options and increases adverse effects and toxicity risk when taking multiple antibiotics. It underscores the need for alternative therapies and multidisciplinary care to address the rising incidence of NTM infections and their associated challenges.