Isoniazid monoresistant tuberculosis treatment outcomes in Puducherry, South India - A mixed methods study.

SETTING: On a programmatic basis, a new regimen was introduced in the National Tuberculosis Elimination Programme for isoniazid monoresistant tuberculosis in a few states in India. OBJECTIVE: To describe the clinical attributes and treatment outcomes of isoniazid mono-resistant tuberculosis patients on the new 6-month levofloxacin-containing regimen in Puducherry, India. DESIGN: The study is designed as a convergent parallel mixed-methods study: a retrospective cohort study and a descriptive qualitative study. A total of 180 Hr-TB patient health records were reviewed, and in-depth interviews with 35 participants were conducted. (20 Hr-TB patients and 15 HCWs). RESULTS: Of the total 180 Hr-TB patients included, we documented unfavourable outcomes in 26.1% of cases, and the KatG gene mutation was the most common mutation observed (63.9%). A significant risk of unfavourable outcomes was associated with low adherence and positive sputum at the third-month culture report. In interviewing the stakeholders, major challenges observed were the increased pill burden, delay in diagnosis, shortage of drugs, and lack of staff. CONCLUSION: Hr-TB patients have difficulty in adhering to the 6-month levofloxacin regimen, with the need for rigorous early 3-month follow-up and assessment.

Pyrazinamide resistance due to pncA gene mutation and its association with treatment outcome among tuberculosis patients of South India- A longitudinal observational study.

INTRODUCTION: Mycobacterium tuberculosis has been extensively studied for mutations leading to drug resistance. Pyrazinamide is a drug acting on the semi-dormant bacteria that is responsible for relapse of tuberculosis. This drug helped reduce the treatment duration of tuberculosis from nine to six months. However, this drug is not being screened for resistance along with Rifampicin and Isoniazid. AIMS AND OBJECTIVES: This study aimed to estimate the proportion of pncA gene mutation among tuberculosis patients and its association between treatment outcomes, clinical characteristics, and phenotypic drug resistance. METHOD: ology: A total of 154 samples included 73 drug-resistant and 81 drug-susceptible isolates. The isolates were subjected to DNA extraction and amplification using conventional PCR. The PCR product was sequenced by the Sanger sequencing method, and phenotypic drug susceptibility testing was done using the broth dilution method. The association of this gene with the treatment outcome was done by following up with the patients till the end of the regimen. RESULTS: None of the drug susceptible tuberculosis patients showed significant non-synonymous mutations. Among the drug-resistant TB patients, seven unique significant mutations out of 73 isolates (9.6%) were distributed among Isoniazid-resistant tuberculosis and Multi-Drug Resistant Tuberculosis isolates. No association was found between the mutations and the clinical characteristics of the subjects harboring these isolates. CONCLUSION: This study estimated seven unique mutations in drug-resistant tuberculosis and none in drug-sensitive tuberculosis. Isolates harboring was not significantly associated with the participant's treatment outcome and other clinical characteristics. The pyrazinamide resistance testing by the phenotypic and genotypic methods was found to be in concordance.