Successful treatment of macrolide-resistant <i>Mycobacterium abscessus</i> infection using multi-drug regimens including dual β-lactams and phage therapy: case reports in two children

ABSTRACT Background Mycobacterium abscessus ( M. abscessus ) infections are poorly responsive to antibiotics, with lower rates of clinical and microbiological clearance for macrolide-resistant isolates compared to macrolide-susceptible strains. Successful treatment of macrolide-resistant M. abscessus infection has not been reported for children. Case Summary Here we report two children with macrolide-resistant M. abscessus infections who achieved clinical remission and microbiologic clearance using multi-drug treatment regimens including clofazimine, bedaquiline, linezolid or eravacycline, dual β-lactam therapy with meropenem and amoxicillin, and, in one case, phage therapy. Conclusion Successful treatment of macrolide-resistant M. abscessus infections in children can be achieved using multi-drug regimens including novel dual β-lactam combinations and phage therapy. Dose adjustment with therapeutic drug monitoring can ameliorate some drug-induced toxicities in children.