Apr 16,2024
Mumbai: A national study of 600 patients with drug-resistant tuberculosis (TB) showed that the majority (51 per cent) had advanced disease in which four or more drugs were ineffective, according to a newly published research paper.
The study, which was conducted by an IIT Bombay startup, Haystacks Analytics, along with the BMC and Pune-based D Y Patil Medical College, used the latest in TB diagnostics called whole genome sequencing . While most samples were sent from Mumbai, samples were also collected from the rest of Maharashtra and a few other states.
Around 51 per cent had pre-extensively drug-resistant (pre-XDR) while 15.5 per cent had the relatively milder multidrug-resistant tuberculosis (MDR-TB) in which two of the known anti-TB drugs are ineffective. While MDR-TB and pre-XDR-TB require 18 to 24 months of treatment, the drug-sensitive form of TB requires nine months of treatment.
The study, published in Microbiology Spectrum, an indexed journal of the American Society of Microbiology , has two main findings. Firstly, it proves that there is active transmission of pre-XDR TB in Mumbai among people in the productive age group; people directly get the deadlier version of the disease from an affected person. Secondly, although the government hasn’t yet included whole genome sequencing (WGS) in the National TB Elimination Programme (NTEP), it appears that the medical fraternity has worked out its guidelines on when to use WGS.
“We asked doctors who sent us the samples of 600 patients for the reason for seeking WGS, and found that their patient was not responding to initial treatment or they had a high degree of suspicion about MDR-TB,” said Anirvan Chatterjee of Haystacks Analytics who is the study’s main author. WGS has been recommended by World Health Organisation to quicken treatment of deadlier forms of TB: WGS can give a report of an 18-drug susceptibility test within 10 to 14 days when traditional culture test takes up to nine weeks.
Chatterjee said, “Even if one out of four or five drugs given to patient doesn’t work for the patients, it will increase resistance to other drugs during the course of the treatment.” Hence, it is better if doctors find out the right drug combinations at the earliest.
Dr Mangala Gomare, former executive health officer of the BMC who is one of the authors, said, “As the study found majority of the referred patients had pre-XDR, WGS should become the norm, or at least we should have proper guidelines for its use.” She added WGS would help customise treatment for patients with drug-resistant forms of the disease. As per BMC’s statistics for TB in 2023, the incidence of TB has dropped by 10 per cent between 2022 and 2023.
Source: Healthworld