What is pre-XDR-TB?

According to the World Health Organization (WHO), pre-extensively drug-resistant tuberculosis (Pre-XDR-TB) is defined as TB caused by Mycobacterium tuberculosis (M. tuberculosis) strains that fulfil the definition of multidrug-resistant and rifampicin- resistant TB (MDR/RR-TB) and which are also resistant to any fluoroquinolone.

MDR-TB: Resistance of Mycobacterium tuberculosis strains to at least isoniazid and rifampicin, the cornerstone medicines for the treatment of TB. Rifampicin-resistant disease on its own requires similar clinical management as MDR-TB.

Whole Genome Sequencing (WBS) is considered an advanced form of testing for TB, revealing the exact strain the patient is suffering from and that too in the shortest possible time. Compared to the traditional tests, which are based on culture reports that take up to nine weeks, the WBS report of the TB bacillus affecting the patient comes within 10 to 15 days.

our analysis, we found that there is a high proportion of pre-XDR in patients who are suspected to be MDR cases.”

Whole genome sequencing is considered an advanced form of testing for TB, reveals the exact strain the patient is suffering from and that too in the shortest possible time. Compared to the traditional tests, which are based on culture reports that take up to nine weeks, the WBS report of the TB bacillus affecting the patient comes within 10 to 15 days.

The study underlined that in the absence of drug-susceptibility profile, patients are usually placed on therapy, which may contain a few drugs to which the TB strain is already resistant, and such therapy ultimately fails because of the risk of amplification of resistance. It said such practices put communities at risk of exposure to increasingly resistant TB bacteria.

The study said delays in diagnosis and an effective treatment of multidrug resistant-TB in the private sector