Tuberculosis (TB) is a public health emergency that continues to kill nearly 1.5 million people each year worldwide. India has the highest TB burden with an estimated incidence of 2.2 million cases out of a global incidence of 8.7 million cases. Drug-resistant TB, known since the introduction of anti-tubercular drugs and evolving from being Mono-Resistant to Multi-Drug Resistant (MDR), extensively Drug Resistant (XDR) & recently Totally Drug Resistant (TDR) is now well established throughout the world. Approximately 3% of all newly diagnosed patients have MDR-TB and the resistance rates are ten times higher in previously treated cases. India is one of highest MDR-TB burden countries in the world, with an estimated 99,000 incident MDRTB cases. One TB/MDR-TB/XDR-TB case if not detected and treated early can potentially infect 15-20 persons annually. This, in combination with the AIDS pandemic, poses a great challenge for treating physicians & global TB control efforts emphasizing the need for rapid & accurate diagnosis of TB and drug-resistant TB. The purpose of this article is to review the conventional & the newer rapid tools for TB diagnosis & their utility in the resource-constrained, high-burden settings.
