1083 - Clinical Efficacy of Tedizolid for the Treatment of Mycobacterium abscessus complex Infections in Solid Organ Transplant Recipients

Background: Mycobacterium abscessus complex is a rapidly growing mycobacteria notoriously refractory to therapy due to inherent antimicrobial resistance mechanisms. Tedizolid is an oxazolidinone with in vitro activity against many nontuberculous mycobacteria species, including M. abscessus complex. This study describes the clinical outcomes of solid organ transplant (SOT) recipients with M. abscessus complex infection treated with tedizolid at a single medical center.

Methods: This retrospective cohort study included adult SOT recipients who met the ATS/IDSA criteria for nontuberculous mycobacterial infection and were treated with a multi-drug regimen that included tedizolid for at least four weeks between January 1, 2010 to August 31, 2019. Symptomatic improvement was defined as either decreased cough or sputum production for pulmonary infection and decrease in size of the primary lesion for skin or surgical site infection. The criteria for a microbiologic response was more than one negative culture with the causative species and sustained until the end of treatment. Clinical cure was defined as improvement of symptoms without proven negative cultures during and sustained until the end of treatment. A patient was considered cured if both symptomatic (if applicable) and microbiologic criteria were fulfilled. The clinical outcomes were compared from the initiation of tedizolid-containing regimen to the end of any M. abscessus complex treatment.

Results: Twelve patients were included. Mycobacterium abscessus abscessus (7/12, 58%) was the most common subspecies. The distribution of infections were as follows: five (42%) disseminated infections, five (42%) pulmonary infections, five (42%) surgical site infections, and four (33%) skin and soft tissue infections. Six patients were cured or clinically cured for all sites of infection (50%), three patients died (25%), and one patient had two recurrences (Table 1).Table 1. Patient demographics and outcomes of M. abscessus complex infection.


Conclusion: Most patients had multiple sites of infection, and treatment required combination antimicrobial therapy and appropriate surgical management. In this small cohort, tedizolid-containing regimens demonstrated a potential benefit in symptomatic and microbiologic improvement in SOT recipients with M. abscessus complex infection.