ISONIAZID MONORESISTANCE : THE NEW CHALLENGE IN DRUG RESISTANT TUBERCULOSIS

Background: Drug resistant tuberculosis is a global threat to overall tuberculosis control. Isoniazid is a critically important rst line drug. Isoniazid monoresistance increases the incidence of treatment failure and relapse. Method: A total of 100 sputum samples positive for acid fast bacilli by Ziehl-Neelsen staining were collected from pulmonary tuberculosis patients between September 2019 to January 2020 (four months) and subjected to Line probe assay (LPA). Result: Mycobacterium tuberculosis complex was detected in all the 100 samples by LPA. It was found that 82 (82%) samples were sensitive to both Isoniazid and Rifampicin, 9(9%) of them were multidrug resistant ,8(8%) were Isoniazid monoresistant and 1(1%) was Rifampicin monoresistant.Out of the Isoniazid monoresistance cases mutation in katG was seen in 87% cases and inhA mutation in 13%. Conclusion: Isoniazid resistance is surprisingly increasing and is missed out by rapid tests.