Published in PLOS One on 2026-04-13, this study is presented as an attributed evidence briefing. The excerpts below are the original researchers’ words, reproduced under their Creative Commons Attribution licence. Health Signal has selected the abstract and, where needed, opening background paragraphs; the complete methods, results, limitations and references remain in the linked paper.
Original authors: Wolde Abreham Geda, Kebede Tefera Betru, Tarekegn Solomon, Solomon Daniel
Source: PLOS One • DOI 10.1371/journal.pone.0327705
Read the complete primary study ↗ · Creative Commons Attribution licence
From the researchers
Abstract
Time to sputum culture conversion is critical for follow-up treatment effectiveness in multidrug-resistant tuberculosis patients. However, the evidence regarding time to culture conversion, treatment outcomes, and the associated factors was sparse and inconsistent.
This study aimed to determine the time to culture conversion, treatment outcomes, and associated factors among rifampicin-resistant and multidrug-resistant tuberculosis cases in the Sidama region from April 1 to December 31, 2024.
We conducted a retrospective follow-up study of 346 patients who enrolled between January 2013 and June 2024. We collected data from patients’ medical records using a standardized form, entered the data, and analyzed it using Stata 16.1 software. We performed the analysis using the Kaplan-Meier model for time to culture conversion, Weibull distribution gamma frailty, and logistic regression models to assess factors associated with time to culture conversion and treatment outcomes, respectively. We considered an adjusted hazard or odds ratio with a 95% CI and a p-value < 0.05 to determine significance.
Among the participants, 302 (87.3%) achieved culture conversion in a median time of 76 days (95% CI: 71–79 days). Patients with a history of previous loss to follow-up experienced an approximately fivefold delay in culture conversion (AHR = 0.2; 95% CI: 0.1–0.6; p = 0.001), while relapse cases had a twofold delay (AHR = 0.5; 95% CI: 0.2–0.9; p = 0.02) compared with new patients. The treatment success rate was 234/346 (67.6%). Female patients had higher odds of achieving a favorable treatment outcome (AOR = 1.8; 95% CI: 1.0–3.3; p = 0.04), whereas patients who experienced culture reversion had significantly lower odds of a favorable outcome (AOR = 0.05; 95% CI: 0–0.4; p = 0.001).
The majority of patients experienced culture conversion within three months. However, patients with a history of loss to follow-up and relapse experienced delayed culture conversion. These findings highlight the urgent need to improve patient adherence.
Introduction
Tuberculosis (TB) is the deadliest infectious disease, but it is curable if patients get the appropriate treatment regimen. Roughly, TB infects a quarter of the global population. However, most infected individuals will not develop active TB disease, and some individuals may recover due to their immune response [1].
Globally, approximately 10.7 million people were diagnosed with TB in 2024 [2]. Among people who were diagnosed with TB, 390,000 people additionally acquired multidrug-resistant/rifampicin mono-resistant-TB (MDR/RR-TB). Ethiopia is one of the 30 countries with a high burden of TB and human immunodeficiency virus (HIV) associated TB. In 2024, the estimated annual incidence of TB was 141 cases per 100,000 people, accompanied by a death rate of 16 per 100,000. Although Ethiopia has transitioned out of the list of countries with high MDR-TB burden since 2020, MDR-TB continues to pose a significant public health challenge. In 2024 alone, an estimated 2500 new cases of RR-TB occurred, with a considerable number of cases remaining undetected [1].
Reading this evidence
Use the full paper to check the study design, participant selection, comparator and outcome definitions before drawing a practical conclusion. An association does not by itself show cause and effect. A reported performance measure needs its denominator and uncertainty. A finding from a particular facility, sample or time period should retain that scope when it is discussed elsewhere.
This briefing makes the source accessible within the wider research & evidence desk. It does not assess an individual patient or certify a product. When considering relevance to another health system, examine the original authors’ account of context and limitations, then seek local implementation evidence. The related reporting below provides other studies to read alongside this one; it is a topic connection, rather than a claim that their results are directly comparable.
© 2026 Wolde Abreham Geda, Kebede Tefera Betru, Tarekegn Solomon, Solomon Daniel. Excerpts reproduced under CC BY. Selection, formatting and contextual notes by Health Signal. The researchers are the authors of the source study, not members of Health Signal’s staff.
Explore connected evidence
- Evidence brief: Predictors of tuberculosis mortality among patients on treatment: A retrospective cohort study at a rural general hospital in Zambia
- Evidence brief: Determinants of favorable treatment outcomes in multidrug-resistant tuberculosis in Zambia: A retrospective cross sectional study, 2018–2022
- Evidence brief: Uncovering overlooked bacterial infections in gene X-pert MTB/RIF negative sputum samples of adult patients with presumptive tuberculosis in Harar, Eastern Ethiopia
