METHOD: This retrospective cohort study was conducted using data from a Malaysian tuberculosis registry, medical records and clinic referral emails from five primary care clinics in Kota Kinabalu from January 2014 to December 2018. A total of 163 patients with delayed sputum smear conversion were selected and divided into cohort groups: 90 patients received 3 months of intensive phase treatment (extended intensive phase), and 73 patients received 2 months of intensive phase treatment (non-extended intensive phase).
RESULTS: Of the 163 patients, 33.7% had unsuccessful treatment outcomes (25.2% had treatment failure; 0.6% died; 3.7% defaulted; and 4.3% transferred out), and 3.7% had relapse. There were no significant differences in the prevalence of unsuccessful treatment outcomes (37.6% vs 28.6%, OR=1.51, CI=0.77-2.94, P=0.226) and relapse (2.2% vs 5.7%, 0R=0.36, CI=0.65-2.04, P=0.404) between the extended and non-extended intensive phase groups. High sputum acid-fast bacilli grade (AFB) at 2 months, drug resistance and lack of directly observed treatment, short-course supervision (DOTS) were associated with unsuccessful treatment outcomes.
CONCLUSION: Extended intensive phase treatment in patients with delayed sputum smear conversion does not prevent unsuccessful treatment outcomes and relapse.