Time to sputum culture conversion and its predictors among drug-resistant tuberculosis patients in Ethiopia: a systematic review and meta-analysis.

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 2851 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.

PROSPERO REGISTRATION NUMBER: CRD420261348090.