Newer diagnostics for tuberculosis and multi-drug resistant tuberculosis.

PURPOSE OF REVIEW: This article will review some of the recent developments for the rapid diagnosis and detection of drug resistance in tuberculosis. RECENT
FINDINGS: Tuberculosis remains one of the major causes of death from a single infectious agent worldwide. Of great concern for tuberculosis control is the emergence of drug resistance since there is no cure for some multidrug-resistant strains of M. tuberculosis, and there is concern that they may spread around the world, stressing the need for additional control measures such as new diagnostics and better drugs for treatment. Recent advances in molecular biology and a better understanding of the molecular basis of drug resistance have provided new tools for rapid tuberculosis diagnosis. Other non-conventional diagnostic approaches have also been proposed. Nucleic acid amplification techniques, both commercial and in-house, and non-molecular methods are being evaluated. The overall accuracy of most of these tests is promising and some of them can be easily implemented in clinical mycobacteriology laboratories.
SUMMARY: New genotypic and phenotypic methods for rapid diagnosis and detection of drug resistance have been developed and tested both in M. tuberculosis strains as well as in clinical samples. Further controlled evaluations are necessary in high-endemic countries for their eventual implementation in the routine diagnostic systems.