Species Identification Of Non-Tuberculous Mycobacteria

Non-tuberculous mycobacteria (NTM) prevalence has risen during recent decades. NTM species identification is crucial for treatment and epidemiologic control since, as opportunistic pathogens, they become sources of infections. Classical biochemical tests and phenotypic methods are not accurate and are time consuming. Other accurate and reliable species identification methods are available. Most are DNA-based from simple PCR-based to those more complex and high-tech based. Not all laboratories can afford technology transfer from simple to more complex and expensive methods, especially in lowincome countries. The price has dropped for some high-tech methods, hence we may think about its possible widespread use, even though some limitations exist regarding data analysis and skill acquisitions. The identification of NTM has been problematic due to their evolving taxonomy, limitations of current phenotypic methods, and absence of a universal gene target for reliable speciation. Accurate NTM identification is a challenging task in diagnostic laboratories due to the absence of a universal robust method and to the difficulty to distinguish between closely related species. This work reviews the most commonly available methods for NTM species identification nowadays.