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There have been rapid technological advances in the detection of Mycobacterium tuberculosis and its drug susceptibility in clinical samples. These include advances in microscopic examination, in vitro culture and application of molecular techniques. The World Health Organization (WHO) has played a large role in evaluating these technologies for their efficacy and feasibility, especially in the developing countries. Amongst these, the Revised National Tuberculosis Control Programme (RNTCP), through its national network of designated microscopy centres and intermediate reference laboratories, has adopted certain technologies that are currently implemented in India. Advances in microscopy technology include fluorescent microscopy using light-emitting diode source, sodium hypochlorite microscopy and vital fluorescent staining of sputum smears. Automation of in vitro culture has markedly reduced the turnaround time (TAT), even in smear-negative samples, and permits simultaneous detection of resistant mutants. Molecular detection of drug resistance has further reduced the TAT, and the cartridge-based nucleic acid amplification test with its performance convenience and rapid results, appears poised to become the future of tuberculosis (TB) diagnosis in all settings, provided the cost of testing is reduced especially for use in private diagnostic settings. This article reviews technologies currently available for the diagnosis of TB, keeping in mind the WHO recommendations and the RNTCP practices. This is a thematic synthesis of data available on diagnosis in literature, preserving the conclusions of the primary studies.

Antimicrobial policy for prophylactic and therapeutic use of antimicrobials in a tertiary care setting has gained importance. A hospital's antimicrobial policy as laid down by its hospital infection control team needs to include inputs from the microbiology laboratory, besides the pharmacy and therapeutic committee. Therefore, it is of utmost importance that clinical microbiologists across India follow international guidelines and also take into account local settings, especially detection and presence of resistance enzymes. This article draws a framework for rational antimicrobial testing in our laboratories in tertiary care centers, from the Clinical and Laboratory Standards Institute guidelines. It does not address testing methodologies but suggests ways and means by which antimicrobial susceptibility reporting can be rendered meaningful not only to the treating physician but also to the resistance monitoring epidemiologist. It hopes to initiate some standardization in rational choice of antimicrobial testing in laboratories in the country pertaining to nonfastidious bacteria.