Is a 6-month Treatment for Isoniazid-resistant Tuberculosis Effective?

Abstract

The objective: to compare treatment efficacy and relapse rates in patients with isoniazid-resistant tuberculosis treated with 9- and 6-month courses of chemotherapy.Subjects and Methods. A retrospective cohort study was conducted. The period from 2010 to 2015 was evaluated. The cases of tuberculosis registered on the territory of Arkhangelsk Region were studied. In 2010-2013, all patients with isoniazid-resistant tuberculosis (n = 130) in the region received a 9-month course of treatment. From 2014 to 2015, the duration of treatment for isoniazid-resistant tuberculosis in the region was reduced from 9 to 6 months. The patients (n = 54) received short-course treatment: aminoglycoside or polypeptide (2 months), rifampicin, pyrazinamide, fluoroquinolone, and ethambutol.There was no statistically significant difference in treatment outcomes of isoniazid-resistant tuberculosis between two regimens: The outcome of effective treatment made 76.2% for the 9-month regimen and 74.1% for the 6-month regimen. The relapse rate per 100 person-years was 0.7 (95% CI 0.1-1.9) for the 9-month regimen and 1.9 (95% CI 0.2-6.7) for the 6-month regimen. This study confirmed the need to decrease the duration of treatment for isoniazid-resistant tuberculosis to 6 months.