[Molecular diagnosis of mycobacteria]

Tuberculosis is one of the leading infectious diseases in the world. Using conventional methods, the isolation, identification, and drug susceptibility testing of Mycobacterium tuberculosis and other clinically important mycobacteria can take several weeks. During the past several years, molecular methods have been developed for direct detection, species identification, and drug susceptibility testing of mycobacteria. These methods can potentially reduce the diagnostic time from weeks to hours. For direct detection of Mycobacterium tuberculosis from clinical specimens, several molecular assays are commercially available today. They have been shown useful for the routine diagnostic laboratory. DNA probes and polymerase chain reaction-based sequencing have been widely used to identify mycobacterial species. Molecular methods have also been applied for the detection of mutations that confer drug resistance in mycobacteria. All in all, the future of clinical mycobacteriology appears to be heading toward direct detection, species identification and drug resistance determination using molecular methods.