Background: Sputum culture conversion at two months is an important indicator for the effectiveness of treatment and the infectivity of a patient with pulmonary TB. This study aimed at investigating factors that are associated with tuberculosis culture conversion at two months as well as investigating whether sputum culture conversion at two months is a reliable predictor of relapse. Methods: The study makes use of data obtained from 347 newly diagnosed tuberculosis patients who participated in a randomized placebo controlled immunotherapy trial at King George V hospital in Durban. Above objectives were met by carrying out statistical analysis of the secondary data. Chi-square tests for categorical explanatory variables such as HIV status and smoking status and (b) t-tests for continuous variables such as age were used for investigating factors associated with 2-month culture conversion. Multivariate models were used to find the most important variables for predicting 2-month culture conversion. Kaplan Meier curves were used for investigating whether culture conversion at two months is a reliable predictor of relapse. Findings: Of the 347 tuberculosis patients, 34 % were HIV sero-positive. Age, body mass index (BMI), smoking status and gender were found to be important variables that affect sputum culture conversion at two months. At 5 % significance level there was no evidence that those who culture convert at two months were less likely to relapse than those who had not culture converted at two months (p=0.1165). However the trend shown is striking to report as it may be of clinical significance. Among those who had not culture converted at two months, more people (40) than expected (34) relapsed an among those who had culture converted at to months, less people (19) than expected (24) relapsed. Interpretation and recommendations: Some behavioral and biological factors affect two month tuberculosis culture conversion therefore successful tuberculosis management need to take into account the effect of these factors. This study did not show that the sterilizing potential of an anti-tuberculosis regimen can be obtained by evaluation of the culture conversion rates at two months and this may be due to small sample size.

Thesis (Th. M.-Miss.)--Fuller Theological Seminary, 1986. / Includes bibliographical references (p. 149-156) and index.

Background: Risk factors for acquired multidrug resistant tuberculosis (MDR TB) are well described but risk factors of primary MDR TB is understudied. We aimed to 1) assess risk factors for primary MDR TB, including diabetes, and 2) determine if diabetes reduced the rate of sputum culture conversion in patients with primary MDR TB. Methods: From 2011-2014 we conducted a prospective cohort study at the National Center for TB and Lung Disease in Tbilisi, Georgia. Adult (≥35 years) patients with primary TB were eligible. MDR TB was defined as resistance to at least rifampicin and isoniazid. Patients with HbA1c ≥6.5% were defined to have diabetes. Polytomous regression was used to estimate the association of patient characteristics with drug resistance. Cox regression was used to compare the hazard rate of sputum culture conversion in patients with and without diabetes. Results: Among 318 patients, 268 had drug susceptibility test results. Among patients with DST results, 19.4% was primary MDR TB and 13.4% had diabetes. In adjusted analyses, diabetes (aOR 2.51 95%CI 1.00 – 6.31) and lower socioeconomic status (aOR 3.51 95%CI 1.56 – 8.20) were associated with primary MDR TB. Among patients with primary MDR TB, 44 (84.6%) converted sputum cultures to negative. The hazard rate of sputum culture conversion was lower among patients with diabetes (aHR 0.34 95%CI 0.13 – 0.87) and among smokers (aHR 0.16 95%CI 0.04 – 0.61). Conclusions: We found diabetes to be associated with an increased risk of primary MDR TB; both diabetes and smoking were associated with a decreased rate of sputum culture conversion.