Successful treatment with clofazimine for macrolide-resistant <i>Mycobacterium abscessus</i> infection in a peritoneal dialysis patient: A case report and literature review

Nontuberculous mycobacteria are rare but serious pathogens in peritoneal dialysis (PD)-associated infections. <i>Mycobacterium abscessus (M. abscessus</i>) is usually resistant to standard anti-tuberculosis drugs. Macrolide antibiotics are key drugs for treating <i>M. abscessus</i>, but macrolide-resistant strains pose particular challenges, and an optimal antimicrobial treatment strategy or duration has not been established for <i>M. abscessus</i> PD-associated infections. We report a case of a 63-year-old man on PD who developed persistent purulent discharge from his PD catheter exit site. Skin swab culture identified macrolide-resistant <i>M. abscessus,</i> with imaging confirming inflammation along the catheter tunnel. These findings led to the diagnosis of <i>M. abscessus</i> PD catheter tunnel infection, with peritonitis excluded. Initial management included early catheter removal, extensive surgical debridement, and 6 weeks of combination antibiotic therapy, including imipenem-cilastatin, amikacin, and clarithromycin, achieving clinical cure. However, the infection recurred after 5 months, necessitating retreatment with debridement and an antibiotic regimen including imipenem-cilastatin, amikacin, azithromycin, and clofazimine for 4 weeks, followed by a continuation regimen with amikacin, clofazimine, and sitafloxacin for 4 months. This approach achieved sustained clinical cure without recurrence at 14 months of follow-up. Based on a literature review of 67 cases of <i>M. abscessus</i> PD-associated infections, all six cases treated with clofazimine achieved clinical cure, but there were no reports on cases of macrolide-resistant <i>M. abscessus</i> treated with clofazimine. Our case represents the first successful clofazimine treatment of macrolide-resistant <i>M. abscessus</i> PD-associated infection, demonstrating clofazimine as a potentially effective oral antibiotic option in combination therapy, particularly in macrolide-resistant cases with limited therapeutic options.