The Effect of Rifabutin in Mycobacterium Abscessus With Inducible Clarithromycin Resistance

Background: Mycobacterium abscessus, one of the most common species of nontuberculous mycobacterium (NTM), poses a significant clinical challenge due to its natural resistance to antibiotics and high treatment failure rates, particularly in lung diseases. Among its subspecies, M. abscessus subspecies abscessus is especially prone to developing inducible resistance to Clarithromycin. This resistance mechanism is primarily due to the activation of the erm(41) gene,which inhibits Clarithromycin from effectively binding to the bacterial ribosome, diminishing its bactericidal efficacy. Rifabutin, an antibiotic widely used in treating tuberculosis and certain NTM infections, has been shown to inhibit the activation of the erm(41) gene by suppressing the whiB7 protein in M. abscessus, suggesting potential efficacy against inducible resistance. However,current evidence primarily stems from in vitro susceptibility studies and case reports, with a notable lack of systematic clinical trials.

Inclusion Criteria: * Adults aged ≥ 18 years * Diagnosis of pulmonary disease caused by Mycobacterium abscessus confirmed by clinical evaluation and laboratory results * Antimicrobial susceptibility testing indicating inducible resistance to clarithromycin * Clinically stable and suitable for antibiotic treatment * Radiographic evidence of active pulmonary infection * Willing and able to provide informed consent Exclusion Criteria: * Known hypersensitivity to rifabutin or intolerance to other study medications * Pregnant or breastfeeding women