Time to Sputum Culture Conversion and Its Predictors Among Multidrug Resistant Tuberculosis Patients in Tigray, Northern Ethiopia: Retrospective Cohort Study

Abstract

Background Sputum culture conversion status is a cardinal index of treatment response and patient outcome for MDR TB patients on longer anti-TB drugs. But, there is limited information on time to sputum culture conversion of MDR TB patients on a longer anti-TB treatment regimen. Therefore, this study aimed to evaluate time to sputum culture conversion and its predictors among MDR TB patients in Tigray, Northern Ethiopia. Methods A retrospective cohort study was conducted from January 2017 through September 2020 among MDR TB patients in Tigray, Northern Ethiopia. Demographic and clinical characteristics including bacteriological data were extracted from the TB registration book and electronic database in Tigray Health Research Institute. Statistical analysis was performed using SPSS version 25. The time to initial sputum culture conversion was analyzed using the Kaplan–Meier method. Bivariate and multivariate Cox proportional hazards regression analyses were used to identify predictors for culture conversions. P <0.05 was considered statistically significant. Results A total of 294 eligible study participants with a median age of 30 years (IQR: 22.75–40) were included. The participants were followed for a total of 1066.7 person months. Sputum culture conversion was achieved in 269 (91%) of the study participants. The median time of sputum culture conversion was 64 days (IQR: 49–86). In our multivariate model, HIV-positive (aHR=1.529, 95% CI: 1.096–2.132, P=0.012), patients new to anti-TB treatment (aHR=2.093, 95% CI: 1.100–3.982, P=0.024) and baseline AFB smear grading of +1 (aHR=1.982, 95% CI: 1.428–2.750, P=0.001) significantly affected time to initial sputum culture conversion. Conclusion The median time of culture conversion was 64 days. Moreover, the majority of the study participants achieved culture conversion within the first six months of treatment commencement, which supports predefined standard treatment durations.

Determinants of sputum culture conversion time in multidrug-resistant tuberculosis patients in ALERT comprehensive specialized hospital, Addis Ababa, Ethiopia: A retrospective cohort study

“…positive baseline cultures, with a median age of 30 years. Similar findings have been reported in previous studies conducted in Ethiopia [12,15]. Similar findings have been reported in previous studies conducted in Ethiopia.…”

“…The duration for culture conversion, as determined by the median, was observed to be 80 days in our study, and similar reports with a median culture conversion time of 85 days and 83 days were reported in China and Latvia respectively [14,20]. On another note, a relatively lower rate of culture conversion median time was reported in Pakistan, Peru, South Africa, and some regions of Ethiopia [10,12,13,15,21,22]. Our result showed a relatively higher culture conversion median time, possibly due to the small sample size employed in our study.…”

“…Amhara region Ethiopia 86.7% [15], Tigray region, Ethiopia 91% [12]. The observed higher culture conversion rate of 89.2% in our study is comparable with the above reports and could be attributed to the rigorous adherence to the standard drug regimen and the meticulous follow-up of MDR-Tuberculosis patients at the center.…”

“…The timeframe necessary for sputum culture conversion following the initiation of treatment serves as a crucial indicator of treatment effectiveness among patients with multidrug-resistant or rifampicin-resistant tuberculosis (MDR/RR-Tuberculosis) undergoing anti-tuberculosis therapy [12][13][14]. In our investigation, we focused on MDR-Tuberculosis patients with initial…”

“…Among our study participants, we observed a 24.2% prevalence of HIV co-morbidity. Conversely, a study conducted in the Tigray region of Ethiopia reported a lower rate of HIV co-morbidity [16]. This disparity could potentially be attributed to the higher prevalence of HIV in Addis Ababa compared to other regions [17].…”