Routine application of high-performance liquid chromatography for identification of mycobacteria

Mycolic acid analysis by high-performance liquid chromatography (HPLC) was introduced in our laboratory as the routine technique for identifying all clinical isolates of mycobacteria referred to us. HPLC identified 96.1% of the 1,103 strains analyzed, whereas the biochemical procedures and/or the commercial DNA probes identified 98.3% of strains, for an overall agreement of 94.4%. Compared with the probes, there was 100% specificity and 98.9% sensitivity for Mycobacterium tuberculosis identification. HPLC allowed early detection and identification of the rare mycobacterial species M. haemophilum, M. malmoense, M. shimoidei, and M. fallax as well as uncharacteristic strains of M. simiae. After 18 months of routine use, HPLC proved to be reliable, easy to perform, rapid, and less costly than other identification methods.