<p>Predictors of Time to Sputum Culture Conversion Among Drug-Resistant Tuberculosis Patients in Oromia Region Hospitals, Ethiopia</p>

Abstract

Purpose: Multi-drug-resistant tuberculosis occurs when the tuberculosis bacteria develop resistance to at least the two most effective first-line anti-tuberculosis drugs, isoniazid and rifampicin. Sputum culture conversion is one of the indicators to monitor patients' prognosis throughout the treatment. Hence, this study aimed to assess time to culture conversion and its determinants among drug-resistant tuberculosis patients. Patients and Methods: A total of 228 drug-resistant tuberculosis patients in selected hospitals in Oromia region, Ethiopia, were included in this study. Descriptive statistics like median time to sputum smear and culture conversion were computed. Bivariate and multivariate Cox proportional hazard models were used to identify the independent predictors of time to culture conversion. The adjusted hazard ratio (AHR) with 95% confidence interval (CI) was used to report the strength of association. Statistical significance was declared at p <0.05. Results: The median age of the study participants was 28 years with inter-quartile range of (IQR) of 22-32 years, and 60% of the patients were male. The median time to culture conversion was 61 days (IQR: 34-92 days). The proportion of sputum culture conversion at 2nd, 4th, and 6th months of treatment initiation was 47%, 82.5%, and 89%, respectively. The final adjusted multivariate Cox proportional hazard model revealed that patients with massive effusion on chest radiographic finding had a 60%-decreased culture conversion time (AHR: 0.4, 95% CI: 0.1-0.9). Patients with abnormalities without cavitations (AHR: 0.5, 95% CI: 0.2-0.9) and those with uninterpreted findings (AHR: 0.3 95% CI: 0.1-0.5) had delayed culture conversion time. Conclusion: Chest radiographic findings such as massive effusion, abnormalities without cavitations, and uninterpreted findings were found to be predictors of time to sputum culture conversion. Patients with such characteristics have prolonged culture conversion time. Hence, they may need special attention during the treatment.

Time to Sputum Smear Conversion and Its Predictors Among Smear-Positive Pulmonary TB Patients in East Gojjam Zone, Northwest Ethiopia: A Longitudinal Study.

“…This study revealed a median sputum smear conversion time of 35 days, IQR: 33 -68 days. This was in line with former studies that reported a median time of 35 days [28] and 34 days with an IQR of 28 -54 [23]. Alternatively, this finding was lower compared to a study finding from Afghanistan [20] where the sputum smear conversion time was 60 days.…”

“…In most studies, the proportion of sputum smear conversion at the end of the 5 th treatment was consistent with our findings [22,23,28]. The proportions of smear conversion at the end of the 2 nd month of treatment on the other hand showed discrepancies with the former studies.…”

“…Little is known about the time to sputum smear conversion among smear-positive PTB cases (SPPTB). Although there are few studies, they are among the MDR-TB patients [23]. In addition, we are not aware of factors that lengthen the sputum smear conversion time.…”

“…Data on socio-demographic, clinical profile and personal behavior-related variables of SPPTB patients were collected using an interviewer-administered questionnaire (S1-quesionnaire). The questionnaire was developed by referring to former similar studies on factors of sputum conversion [20,22,23]. The questionnaire was pretested among SPPTB patients from health facilities outside of the study area but having the same characteristics.…”

“…Most of the developing countries lacked information on the time to smear conversion due to poor documentation, absence of TB diagnostic tools, and poor TB program monitoring strategies [18,20,21]. Similarly, identifying determinant factors that resulted in delayed sputum smear conversion is also vital to improve the effectiveness of TB treatment follow up [20,22,23]. The situation has no exception to the Ethiopian TB prevention and control programs [21].…”