Effect of six- versus eight-month regimen on treatment success and smear conversion among retreatment patients

Background: In 2017, the regimen for patients with retreatment tuberculosis (TB) changed from an eight-month treatment regimen that consisted of Isoniazid, Rifampicin, Pyrazinamide, Ethambutol, and Streptomycin (2RHZES/1RHZE/5RHE) to a six-month treatment regimen (2RHZE/4RH). Currently, there is uncertainty regarding the effect of the six-month treatment regimen on treatment outcomes across TB Control Programs. We evaluated the effect of the six-month treatment regimen on treatment success rate (TSR) and sputum smear conversion (SSC) among patients with retreatment pulmonary bacteriologically confirmed TB (PBC-TB) in Kampala, Uganda.
Methods: Between November 2021 and February 2022, we abstracted data for patients with retreatment PBC-TB who had received treatment between January 2012 and July 2021 across six large TB clinics in Kampala, Uganda. The primary outcome was TSR defined as cure or treatment completed. The secondary outcome was SSC defined as a change in sputum smear test resu...