RESUMO
Purpose: We sought to determine the characteristics and relative frequency of transmission of MDR‑TB in North India and their association with the clinical and epidemiological characteristics of TB‑patients. Materials and Methods: To achieve the objectives PCR‑SSCP, MAS‑PCR and direct DNA sequencing were used against 101 Mycobacterium tuberculosis isolates. Results: Multidrug‑resistant‑TB isolates were found to be significantly higher (P = 0.000) in previously treated patients in comparison to newly diagnosed patients. Further, significant differences (P = 0.003) were observed between different age groups (Mean ± SD, 28.6 ± 11.77) of the TB patients and multidrug resistance. Most frequent mutations were observed at codons 531 and 315 of rpoB and katG genes, respectively, in MDR‑TB isolates. Conclusion: Routine surveillance of resistance to anti‑TB drugs will improve timely recognition of MDR‑TB cases and help prevent further transmission in Northern India.