Clinical and mutational profile of extensively drug resistant tuberculosis cases in northern India

<b>Introduction:</b> Insight into the clinical characteristics and mutational profile of XDR TB cases is essential to reduce the incidence and effectively treat the cases of XDR TB, which has remained a challenge. <b>Aim:</b> To identify the clinical and mutational profile in cases of extensively drug resistant tuberculosis. <b>Objectives:</b> ·&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; To identify the clinical profile in cases of XDR TB. To identify the mutations and drug-resistance pattern as detected by First and Second-Line Line Probe Assay in cases of XDR TB. <b>Methodology:</b> 53 patients newly diagnosed with XDR TB referred to nodal DR-TB Centre KGMU, Lucknow from the period of 1st May 2019 to 30th April 2020 were enrolled. A comprehensive oral and documented history was used to determine the clinical history and prior treatment details. The results of Line Probe Assays(<i>GenoType</i> MTBDR<i>plus</i>(ver2) and <i>GenoType</i> MTBDR<i>sl</i>(ver2)) were analysed for mutation pattern and interpreted for drug resistance. <b>Results &amp; Conclusion:</b> The patients had a median symptom duration of 14 months. An anti-tubercular regimen was being initiated for a median of 3rd time, with a 13 month median duration of previous ATT intake, second-line drugs being consumed for a median of 7 months. The most prevalent mutations conferring resistance to rifampicin, isoniazid, fluoroquinolones and second-line injectables were <i>rpoB</i> S531L, <i>katG</i> S315T1, <i>gyrA</i> D94G, and <i>rrs</i> a1401g respectively. In addition to being resistant to rifampicin, isoniazid, levofloxacin and kanamycin, 52.83%, 75.47%, 91.30% and 17.39% were resistant to high dose moxifloxacin, amikacin/capreomycin, high dose isoniazid and ethionamide respectively.