Multidrug and extensively drug-resistant TB (M/XDR-TB): problems and solutions.

Multi Drug Resistant Tuberculosis (MDR-TB) and Extensively Drug Resistant Tuberculosis (XDR-TB) are posing a threat to the control of tuberculosis. The first WHO-IUATLD antituberculosis drug resistance surveillance carried out in 1994 in 35 countries reported the median prevalence of primary and acquired multi drug resistance as 1.4% and 13% respectively. Subsequently, second, third and fourth WHO-IUATLD global drug resistance surveillances were carried out in 1996-99, 1999-2002 and 2002-2007 respectively. Based on drug resistance information from 114 countries, the proportion of MDR-TB among all cases was estimated for countries with no survey information. It was estimated that 4,89,139 cases of MDR-TB emerged in 2006. China and India carry approximately 50% of the global burden. 35 countries and two Special Administrative Regions (SARs) reported data on XDR-TB for the first time in 2006. Multidrug and extensively drug-resistant TB 2010 Global report on Surveillance and response estimated that 4,40,000 cases of MDR-TB emerged globally in 2008 and caused an estimated 1,50,000 deaths. 5.4% of MDR-TB cases were found to have XDR-TB. To date, a cumulative total of 58 countries have confirmed at least one case of XDR-TB. M/XDR-TB is a man-made problem and its emergence can be prevented by prompt diagnosis and effective use of first line drugs in every new patient. The DOTS Plus proposed by WHO highlights the comprehensive management strategy to control MDR-TB. Laboratory services for adequate and timely diagnosis of M/XDR-TB must be strengthened and programmatic management of M/XDR-TB must be scaled up as per target set by global plan. Proper use of second-line drugs must be ensured to cure existing MDR-TB, to reduce its transmission and to prevent XDR-TB. Sound infection control measures to avoid further transmission of M/XDR-TB and research towards development of new diagnostics, drugs and vaccines should be promoted to control M/XDR-TB.