Rapid detection of mutations in erm(41) and rrl associated with clarithromycin resistance in Mycobacterium abscessus complex by denaturing gradient gel electrophoresis.

Clarithromycin resistance is increasing dramatically among Mycobacterium abscessus complex. The main resistance mechanisms are mutations in the erm(41) and rrl genes. Here we report PCR-based denaturing gradient gel electrophoresis (DGGE) as an alternative method for rapidly detection of mutations in erm(41) and rrl among M. abscessus isolates. Four primer sets targeting the full-length erm(41) gene and a 354bp fragment of the rrl gene were designed. A combination of 16 different DGGE patterns were observed for erm(41) gene, including 16 in M. abscessus subsp. abscessus and 1 in M. abscessus subsp. massiliense. Six DGGE patterns were obtained for rrl gene. Mutations in the erm(41) and rrl detected by DGGE were 100% identical to mutations detected by DNA sequencing. This is the first report to identify PCR-based DGGE as a practical, relatively inexpensive technique for rapidly detecting mutations in the erm(41) and rrl genes associated with clarithromycin resistance in M. abscessus complex.