Time to Sputum Culture Conversion and Its Predictors Among Drug-Resistant Tuberculosis Patients in Ethiopia: A Systematic Review and Meta-Analysis.

Abstract

BACKGROUND: Drug-resistant tuberculosis remains a major public health challenge in Ethiopia. Delayed sputum culture conversion prolongs infectiousness and worsens treatment outcomes, yet evidence on its timing and predictors is inconsistent. OBJECTIVE: To estimate the pooled time to sputum culture conversion and identify its predictors among drug-resistant tuberculosis patients in Ethiopia. METHODS: A systematic search of PubMed, Google Scholar, Embase, Scopus, Web of Science, and Ethiopian university repositories was conducted for studies published between January 2000 and March 2026. Data were analyzed using R (version 4.4.2) and Stata/MP 17. Heterogeneity and publication bias were assessed. Subgroup analyses and sensitivity analysis explored sources of variation. RESULTS: Eleven retrospective cohort studies with 2,851 patients were included. The pooled median time to sputum culture conversion was 68.92 days (IQR: 57.64-80.19; I²=99.87%). Delayed conversion was associated with previous anti-tuberculosis treatment (aHR=0.46; 95% CI: 0.33-0.64), smear grades (+2: aHR=0.42; 95% CI: 0.26-0.68, and +3: aHR=0.42; 95% CI: 0.29-0.61), underweight status (aHR=0.75; 95% CI: 0.65-0.84), and lung cavitation (aHR = 0.48; 95% CI: 0.33-0.69). CONCLUSION: Culture conversion occurs at approximately two months. Identified risk factors highlight the need for early risk stratification, nutritional support, and close monitoring to improve outcomes.