A role of first line- line probe assay in previously treated cases of pulmonary tuberculosis: A retrospective study

Abstract

Introduction: India has a high tuberculosis burden country with second highest burden of MDR TB (Multidrug Resistant Tuberculosis) in the world. For rapid diagnosis of tuberculosis and drug sensitivity under National Tuberculosis Elimination Programme (NTEP) molecular method like Line Probe assay (LPA) is used in previously treated case of pulmonary tuberculosis at the time of diagnosis. Along with diagnosis, LPA provides result of drug sensitivity of Rifampicin and Isoniazid in same sitting within 72 hours. Method: Retrospectively we have collected data from NTEP register from January to December 2019 of first line-line probe assays done in previously treated cases of sputum positive pulmonary tuberculosis at the time of diagnosis. Aims and objectives of this study are to find out drug sensitivity pattern of Rifampicin and Isoniazid based on LPA results in previously treated cases of tuberculosis. Result: Out of 196 samples, LPA was positive in 187 samples with male-to-female ratio 2.5:1. Maximum number of patients were in age group 18-40 years followed by 41-64 years. Out of 187 positive LPA reports 6.6 % were Isoniazid monoresistance, 4% Rifampicin monoresistance, 4.5 % resistance to both Isoniazid and Rifampicin seen. Patients were put on antitubercular medications according to drug sensitivity and resistance pattern as per NTEP guidelines. Conclusion: By rapid molecular method like LPA, early diagnosis of tuberculosis and drug sensitivity testing in same sitting help in timely and effective management of disease. Early initiation of antitubercular treatment also decreases tuberculous transmission in community.