engleski

Evaluation of matrix-assisted laser desorption (ionization time-of-flight mass spectrometry in identification of nontuberculous mycobacteria

Background/Aims: Species-level identification of nontuberculous mycobacteria (NTM) is important in making decision about the necessity and choice of antimicrobial treatment. The reason is predictable clinical significance and susceptibility profile of specific NTM species. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) is recognized as a new diagnostic tool for routine identification of bacteria and yeasts in the clinical laboratory based on protein fingerprints analysis. The aim of the study was to evaluate MALDI-TOF MS in identification of NTM. Methods: A total of 25 NTM isolates from liquid cultures were identified with both, PCR-based hybridization assay and MALDI-TOF MS at the University Hospital Centre Zagreb. Results: PCR-based hybridization assay identified 96% (24/25) and MALDI-TOF MS 80% (20/25) of tested NTM isolates. Five isolates with no reliable MALDI-TOF MS identification belonged to Mycobacterium avium – intracellulare complex. Seventy percent (14/20) of NTM isolates successfully identified with MALDI-TOF MS had score higher than 2.0 indicating reliable species identification. Conclusion: MALDI-TOF MS is a promising tool for identification of NTM. With a further improvement of protein extraction protocol, especially regarding M. avium – intracellulare complex, MALDI-TOF MS could be an additional standard method for identification of NTM.

MALDI-TOF ; identification ; nontuberculous mycobacteria

nije evidentirano