Treatment Outcomes of Isoniazid-Resistant Tuberculosis Patients, Western Cape Province, South Africa

We report treatment outcomes from a retrospective cohort of patients with isoniazid-monoresistant tuberculosis in rural South Africa. Sixteen percent of patients had poor outcomes, 61% of whom progressed to multidrug-resistant tuberculosis. These data reveal the need for early identification and aggressive follow-up of isoniazid monoresistance to increase treatment success.