Inaccuracy of Single-Target Sequencing for Discriminating Species of the Mycobacterium abscessus Group

We determined nucleotide sequences of rpoB , hsp65 , and sodA in 59 clinical isolates (from 58 patients) of the M ycobacterium abscessus group. Identification to the species level, based on three target genes, was concordant for 44 isolates (25 M. abscessus , 13 Mycobacterium massiliense , and 6 Mycobacterium bolletii isolates) and discordant for 15 isolates which had “interspecific composite patterns.” Sequence analysis of five housekeeping genes also showed composite patterns in 8 of these 15 isolates.