Delay in sputum smear conversion and outcomes of smear-positive tuberculosis patients: a retrospective cohort study in Bafoussam, Cameroon.

BACKGROUND: In limited resource settings, sputum smear conversion at the end of the intensive phase of tuberculosis treatment is an indicator not only of patients' response to treatment, but also of anti-tuberculosis program performance. The objective of this study was to identify factors associated to sputum smear non-conversion at the end of the intensive phase of treatment, and the effect of smear non-conversion on the outcome of smear-positive pulmonary tuberculosis patients. METHOD: This retrospective cohort study was carried out on data of patients treated in the Diagnostic and Treatment Centre of Baleng, West-Cameroon from 2006 to 2012. Logistic regression models were used to evaluate the association of socio-demographic and clinical factors with delay in sputum smear conversion, and the association of this delay with treatment outcomes. RESULT: Out of 1425 smear-positive pulmonary tuberculosis patients treated during the study period, 1286 (90.2%) were included in the analysis. Ninety four (7.3% CI: 6.0- 8.9) patients were identified as non-converted at the end of the intensive phase of treatment. Pre-treatment smears graded 2+ and 3+ were independently associated to delay in smear conversion (p<0.01). Years of treatment ranging from 2009 to 2012 were also associated to delay in smear conversion (p<0.02). Delay in smear conversion was significantly associated to failure [Adjusted Odd Ratio (AOR):12.4 (Confidence Interval: CI 4.0- 39.0)] and death, AOR: 3.6 (CI 1.5- 9.0). CONCLUSION: Heavy initial bacillary load and treatment years ranging from 2009 to 2012 were associated to sputum smear non-conversion at the end of the intensive phase of TB treatment. Also, delay in smear conversion was associated to unfavorable treatment outcomes. Patients with heavy initial bacillary load should thus be closely monitored and studies done to identify reasons for the high proportion of non-conversion among patients treated between 2009 and 2012.

Determinants of death among tuberculosis patients in a semi urban diagnostic and treatment centre of Bafoussam, West Cameroon: a retrospective case-control study.

INTRODUCTION: Tuberculosis (TB) remains a worldwide public health problem with 8.6 millions of new cases and 1.3 millions of death annually. Despite the progress recorded in fighting against this disease in the recent years, Africa is still not on the track to achieve the objective to reduce by half the death rate due to this disease by 2015. METHODS: A case-control study was conducted on data of patients admitted for tuberculosis between 1996 and 2011 in the Diagnostic and Treatment Center of Baleng. Cases were patients who died from any cause during anti tuberculosis treatment. Logistic regression model was used to identify factors associated to death. RESULTS: In 4201 patients treated during the study period, 3245 (77.24%) were included in the study. The mean age was 35.9 (SD 14.2) and male represent 62.2% (CI 60.6- 63.9) of them. At the end of the follow up, 2883 patients were successfully treated, 362 died during treatment and 132 (36.5%) deaths occurred during the first two months of TB treatment. HIV positive status, Extra-pulmonary TB, sputum smear-negative pulmonary TB and male sex were significant independent risk factors of death with adjusted odds ratio of 4.8 (CI 3.2- 7.4); 3.0 (CI 1.6- 5.4); 2.7 (CI 1.7- 4.4) and 1.5 (CI 1.0- 2.3) respectively. CONCLUSION: The mortality rate of TB patients undergoing TB treatment remains high. Studies are needed to identify and test efficient interventions of mortality reduction among TB patients in resource limiting settings.