Clinical emergence of inducible macrolide resistance mediated by acquired erm(41) C28T mutation in Mycobacterium abscessus.

Inducible macrolide resistance mediated by the erm(41) T28 allele is a well-established intrinsic mechanism in Mycobacterium abscessus. Here, we report a case of M. abscessus pulmonary disease in which an initial erm(41) C28 isolate developed inducible resistance through a de novo C28T point mutation during prolonged therapy. To our knowledge, this case provides the first clinical evidence that erm(41)-mediated inducible resistance can arise in vivo under antimicrobial selective pressure.