Pyrolysis Mass Spectrometry: A New Method to Differentiate Between the Mycobacteria of the "Tuberculosis Complex" and Other Mycobacteria

Abstract

Pyrolysis mass spectrometry (p.m.s.) was applied to differentiate 91 coded mycobacteria as belonging to the tuberculosis complex (Mycobacterium tuberculosis, M. bovis and M. bovis BCG) or to other Mycobacterium spp. Strains were analyzed in batches; in each batch, 3 strains each of M. tuberculosis, M. bovis and M. bovis BCG were included as references. Mass spectra were evaluated by computerized multivariate analysis. A 92% positive correlation with classical identification tests was found (2.2% false negative, 5.5% false positive). Approaches for further improvement of this score are indicated. High speed and complete automation of sample anlaysis and computerized data-processing make p.m.s. a potential tool for routine application. Sample transfer from peripheral laboratories to a p.m.s. facility is easy, as samples can be sterilized before shipping.