Differentiation of mycobacterium chelonae and M. abscessus using SmartCycler PCR and MGB eclipse probes

This poster discusses how the use of partial 16S rDNA sequencing (first one-third of the gene) for the identification of Mycobacterium species from cultured isolates has become recognized as a very accurate method for identification. The distinction between M. chelonae and M. abscessus, however, is not possible with partial 16S rDNA sequencing and therefore requires additional testing. Conventional tests that have been used for the distinction include growth on 5% sodium chloride and growth on citrate medium, both of which have been problematic with test inaccuracies and prolonged turnaround time. Restriction analysis of an amplified fragment of the hsp65 gene can distinguish M. chelonae from M. abscessus, but this requires gel analysis and interpretation of fragment sizes and is sometimes difficult because of the similarity of restriction patterns. In this study we developed a simple and rapid method using real-time PCR with the SmartCycler TM (Cepheid, Sunnyvale, CA) to distinguish M.