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

Abstract

Background: Sputum smear conversion is a key indicator of treatment response and reduced infectivity among smear-positive pulmonary tuberculosis (SPPTB). This study aimed at estimating sputum smear conversion time and identifying factors hindering sputum smear conversion among SPPTB patients in East Gojjam Zone, Northwest Ethiopia. Methods: A total of 282 SPPTB patients were followed for 22 weeks through weekly sputum smear evaluation. Due to the absence of sputum culture and rapid diagnostic services, sputum smear conversion evaluation was conducted microscopically using acid-fast-bacilli staining technique of sediments from a 5% sodium hypochlorite concentration technique. Data on socio-demographic, clinical profile, and personal behavior variables were collected using a pretested interviewer-administered questionnaire. Various descriptive statistics including mean, median with interquartile range (IQR), proportions, and cross-tabulations were computed. Factors affecting sputum smear conversion were identified by multivariable logistic regression analysis. The statistical significance of variables was determined at a p-value < 0.05. Results: Over half, 166(59%) of SPPTB cases were males and 147(52%) were rural dwellers. The mean age of respondents was 35±5SD years. About 88(31.2%) of SPPTB patients had comorbidities, 102(36.2%) faced stigma, and 54(19%) smoked a cigarette. The median sputum smear conversion time at the end of the intensive phase was 35 days (IQR: 21 -56 days). The majority, 85% (95%CI: 76% -93%) and 95% (95% CI: 85% -99%) of SPPTB patients underwent sputum smear conversion at the end of 2nd and 5th months of treatment, respectively. Poor knowledge on TB, being HIV positive, higher smear grading, having diabetes mellitus, undernutrition, cigarette smoking, facing societal stigma, and TB service delay were positively associated with the length of sputum smear conversion. Conclusion: Although the treatment success rate was 95%, the median sputum smear conversion time was higher compared to the TB program expectations and some former studies. Factors of sputum smear conversion were related to nutritional status, smear grading, comorbidity status, knowledge on TB, personal behavior, stigma, and TB service delay. Improving the health literacy of the community by revising the existing community awareness strategies is essential to enhance treatment adherence and lower infectiousness after treatment initiation.