A paradigm for the molecular identification of Mycobacterium species in a routine diagnostic laboratory

1 Department of Microbiology, Royal Free Hospital, London NW3 2QG, UK 2 Centre for Medical Microbiology, Hampstead Campus, University College London, London NW3 2PF, UK Correspondence T. D. McHugh t.mchugh{at}medsch.ucl.ac.uk Received 26 July 2006 Accepted 10 January 2007 The aim of this study was to improve the identification of Mycobacterium species in the context of a UK teaching hospital. Real-time PCR assays were established to enable the rapid differentiation between Mycobacterium tuberculosis (MTB) complex and Mycobacterium species other than tuberculosis (MOTT), followed by 16S rRNA gene sequencing for the speciation of MOTT. Real-time PCR assays gave comparable results to those from the reference laboratory. The implementation of these PCR assays using an improved bead extraction method has enhanced the mycobacterial diagnostic service at the Royal Free Hospital by providing a rapid means of differentiating between MTB complex and MOTT, and would be simple to implement in similar laboratories. Sequence analysis successfully identified a range of Mycobacterium spp. representative of those encountered in the clinical setting of the authors, including Mycobacterium avium complex, Mycobacterium fortuitum group, Mycobacterium chelonae – Mycobacterium abscessus group, Mycobacterium xenopi and Mycobacterium gordonae . It provides a useful tool for the identification of MOTT when clinically indicated. Abbreviations: MOTT, Mycobacterium species other than tuberculosis ; MTB, Mycobacterium tuberculosis .