Browsing by Author "Ellner, Jerrold J."

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    Drug Tolerance in Mycobacterium tuberculosis
    (Antimicrobial agents and chemotherapy, 1999) Wallis, Robert S.; Patil, Shripad; Cheon, Seon-Hee; Edmonds, Kay; Phillips, Manijeh; Perkins, Mark D.; Joloba, Moses; Namale, Alice; Johnson, John L.; Teixeira, Lucileia; Dietze, Reynaldo; Siddiqi, Salman; Mugerwa, Roy D.; Eisenach, Kathleen; Ellner, Jerrold J.
    Although Mycobacterium tuberculosis is eradicated rapidly during therapy in some patients with pulmonary tuberculosis, it can persist for many months in others. This study examined the relationship between mycobacterial drug tolerance (delayed killing in vitro), persistence, and relapse. It was performed with 39 fully drug-susceptible isolates from a prospective trial of standard short-course antituberculous therapy with sputum smear-positive, human immunodeficiency virus-uninfected subjects with pulmonary tuberculosis in Brazil and Uganda. The rate of killing in vitro was determined by monitoring the growth index (GI) in BACTEC 12B medium after addition of drug to established cultures and was measured as the number of days required for 99% sterilization. Drugs differed significantly in bactericidal activity, in the following order from greatest to least, rifampin > isoniazid-ethambutol > ethambutol (P < 0.001). Isolates from subjects who had relapses (n 5 2) or in whom persistence was prolonged (n 5 1) were significantly more tolerant of isoniazidethambutol and rifampin than isolates from other subjects (P < 0.01).
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    Effectiveness of the standard WHO recommended retreatment regimen (Category II) for tuberculosis in Kampala, Uganda
    (PLoS medicine, 2011) Jones-López, Edward C.; Ayakaka, Irene; Levin, Jonathan; Reilly, Nancy; Mumbowa, Francis; Dryden-Peterson, Scott; Nyakoojo, Grace; Fennelly, Kevin; Temple, Beth; Nakubulwa, Susan; Joloba, Moses L.; Okwera, Alphonse; Eisenach, Kathleen D.; McNerney, Ruth; Elliott, Alison M.; Ellner, Jerrold J.; Smith, Peter G.; Mugerwa, Roy D.
    Each year, 10%–20% of patients with tuberculosis (TB) in low- and middle-income countries present with previously treated TB and are empirically started on a World Health Organization (WHO)-recommended standardized retreatment regimen. The effectiveness of this retreatment regimen has not been systematically evaluated. Methods and Findings: From July 2003 to January 2007, we enrolled smear-positive, pulmonary TB patients into a prospective cohort to study treatment outcomes and mortality during and after treatment with the standardized retreatment regimen. Median time of follow-up was 21 months (interquartile range 12–33 months). A total of 29/148 (20%) HIV-uninfected and 37/140 (26%) HIV-infected patients had an unsuccessful treatment outcome. In a multiple logistic regression analysis to adjust for confounding, factors associated with an unsuccessful treatment outcome were poor adherence (adjusted odds ratio [aOR] associated with missing half or more of scheduled doses 2.39; 95% confidence interval (CI) 1.10–5.22), HIV infection (2.16; 1.01–4.61), age (aOR for 10-year increase 1.59; 1.13–2.25), and duration of TB symptoms (aOR for 1-month increase 1.12; 1.04–1.20). All patients with multidrug-resistant TB had an unsuccessful treatment outcome. HIV-infected individuals were more likely to die than HIV-uninfected individuals (p,0.0001). Multidrug-resistant TB at enrolment was the only common risk factor for death during follow-up for both HIV-infected (adjusted hazard ratio [aHR] 17.9; 6.0–53.4) and HIV-uninfected (14.7; 4.1–52.2) individuals. Other risk factors for death during follow-up among HIVinfected patients were CD4,50 cells/ml and no antiretroviral treatment (aHR 7.4, compared to patients with CD4$200; 3.0– 18.8) and Karnofsky score ,70 (2.1; 1.1–4.1); and among HIV-uninfected patients were poor adherence (missing half or more of doses) (3.5; 1.1–10.6) and duration of TB symptoms (aHR for a 1-month increase 1.9; 1.0–3.5). Conclusions: The recommended regimen for retreatment TB in Uganda yields an unacceptable proportion of unsuccessful outcomes. There is a need to evaluate new treatment strategies in these patients.
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    First Trial Of The HIV­1 Vaccine In Africa: Ugandan Experience
    (Bmj, 2002) Mugerwa, Roy D.; Kaleebu, Pontiano; Mugyenyi, Peter; ­Mbidde, Edward Katongole; Hom, David L.; Byaruhanga, Rose; Salata, Robert A.; Ellner, Jerrold J.; HIV­1 Vaccine Trial Group
    Trials of the HIV­1 vaccine have been conducted in Europe, North America, Brazil, China, and Thailand.1 The first trial of a candidate vaccine in Africa was recently completed in Uganda. It involved a ran­domised, placebo controlled trial of a vaccine in healthy volunteers at low risk of HIV infection.2 3 The vaccine, called “ALVAC­HIV,” uses a live recombinant canarypox vector to express envelope and core genes of HIV­1. Many commentators predicted that it would be dif­ficult to conduct trials of HIV vaccines in developing countries because of scientific, sociobehavioural, ethical, and logistical barriers.4–8 Before we started the trial in Uganda, we gathered data to help us overcome these potential barriers. We collected epidemiological9 and sociobehavioural10 data about people who had participated in studies that looked at preparing for trials of the HIV vaccine. These data showed the preva­lence and incidence of HIV, behaviours placing people at risk of becoming infected with HIV, and the social acceptability of a vaccine against HIV.9–11 The people received detailed education and counselling about infection with HIV and about HIV vaccines, and we recruited some for our trial.11We organised three open workshops at the HIV candidate vaccine trial workshop in Kampala in 1996 to gain consensus from scientists, policy makers, community representatives, and the media about how to undertake research into HIV vaccines. Despite these initiatives to solve problems before the trial began, we still encountered many barriers. In this article, we discuss these barriers and the strategiesthat we developed to overcome them.
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    Induction of the Antigen 85 Complex of Mycobacterium tuberculosis in Sputum: A Determinant of Outcome in Pulmonary Tuberculosis Treatment
    (The Journal of infectious diseases, 1998) Wallis, Robert S.; Perkins, Mark; Phillips, Manijeh; Joloba, Moses; Demchuk, Barbara; Namale, Alice; Johnson, John L.; Williams, Donna; Wolski, Kathy; Dietze, Reynaldo; Mugerwa, Roy D.; Eisenach, Kathleen; Ellner, Jerrold J.
    Sputum quantitative culture, acid-fast smear, days-to-positive by BACTEC, and Mycobacterium tuberculosis antigen 85 complex were monitored during therapy in 42 patients with pulmonary tuberculosis (TB). By BACTEC, 4 patients were persistently positive on days 90–180, and treatment ultimately failed in 2 of these. Antigen 85 expression increased in subjects in whom disease persisted (persisters) from days 0 to 14 when the difference between persisters and nonpersisters was statistically significant (P .002). Only antigen 85 complex values at day 14 suggested TB persistence at or after day 90. All subjects with day 14 antigen 85 complex values 60 pg/mL responded rapidly to treatment and were cured. Of those with values 60 pg/mL, in 33% TB persisted at or after day 90 and treatment failed in 17%. Biologic factors expressed early in therapy, not related to compliance or resistance, may exert a substantial influence on outcome. The antigen 85 complex is critical in cell wall biosynthesis and is induced by isoniazid in vitro. Its induction may represent an adaptive transition to a persistent state during therapy
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    Predictors and outcomes of mycobacteremia among HIV-infected smear- negative presumptive tuberculosis patients in Uganda
    (BMC infectious Diseases, 2015) Nakiyingi, Lydia; Ssengooba, Willy; Nakanjako, Damalie; Armstrong, Derek; Kirenga, Bruce J.; Mayanja-Kizza, Harriet; Joloba, Moses L.; Ellner, Jerrold J.; Dorman, Susan E.; Manabe, Yukari C.
    Sputum smear microscopy for tuberculosis (TB) diagnosis lacks sensitivity in HIV-infected symptomatic patients and increases the likelihood that mycobacterial infections particularly disseminated TB will be missed; delays in diagnosis can be fatal. Given the duration for MTB growth in blood culture, clinical predictors of MTB bacteremia may improve early diagnosis of mycobacteremia. We describe the predictors and mortality outcome of mycobacteremia among HIV-infected sputum smear-negative presumptive TB patients in a high prevalence HIV/TB setting.Between January and November 2011, all consenting HIV-infected adults suspected to have TB (presumptive TB) were consecutively enrolled. Diagnostic assessment included sputum smear microscopy, urine Determine TB lipoarabinomannan (LAM) antigen test, mycobacterial sputum and blood cultures, chest X-ray, and CD4 cell counts in addition to clinical and socio-demographic data. Patients were followed for 12 months post-enrolment.Of 394 sputum smear-negative participants [female, 63.7%; median age (IQR) 32 (28–39) years], 41/394 (10.4%) had positive mycobacterial blood cultures (mycobacteremia); all isolates were M. tuberculosis (MTB). The median CD4 cell count was significantly lower among patients with mycobacteremia when compared with those without (CD4 31 versus 122 cells/μL, p < 0.001). In a multivariate analysis, male gender [OR 3.4, 95%CI (1.4-7.6), p = 0.005], CD4 count <100 cells/μL [OR 3.1, 95% CI (1.1-8.6), p = 0.030] and a positive lateral flow urine TB LAM antigen test [OR 15.3, 95%CI (5.7-41.1), p < 0.001] were significantly associated with mycobacteremia. At 12 months of follow-up, a trend towards increased mortality was observed in patients that were MTB blood culture positive (35.3%) compared with those that were MTB blood culture negative (23.3%) (p = 0.065). Mycobacteremia occurred in 10% of smear-negative patients and was associated with higher mortality compared with smear-negative patients without mycobacteremia. Advanced HIV disease (CD4 < 100 cells/mm3), male gender and positive lateral flow urine TB LAM test predicted mycobacteremia in HIV-infected smear-negative presumptive TB patients in this high prevalence TB/HIV setting.
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    Rate and Amplification of Drug Resistance among Previously-Treated Patients with Tuberculosis in Kampala, Uganda
    (Clinical infectious diseases, 2008) Temple, Beth; Ayakaka, Irene; Ogwang, Sam; Nabanjja, Helen; Kayes, Susan; Nakubulwa, Susan; Worodria, William; Levin, Jonathan; Joloba, Moses; Okwera, Alphonse; Eisenach, Kathleen D.; McNerney, Ruth; Elliott, Alison M.; Smith, Peter G.; Mugerwa, Roy D.; Ellner, Jerrold J.; Jones-Lopez, Edward C.
    Drug-resistant Mycobacterium tuberculosis has emerged as a global threat. In resource-constrained settings, patients with a history of tuberculosis (TB) treatment may have drug-resistant disease and may experience poor outcomes. There is a need to measure the extent of and risk factors for drug resistance in such patients. Methods. From July 2003 through November 2006, we enrolled 410 previously treated patients with TB in Kampala, Uganda. We measured the prevalence of resistance to first- and second-line drugs and analyzed risk factors associated with baseline and acquired drug resistance. Results. The prevalence of multidrug-resistant TB was 12.7% (95% confidence interval [95% CI], 9.6%–16.3%). Resistance to second-line drugs was low. Factors associated with multidrug-resistant TB at enrollment included a history of treatment failure (odds ratio, 23.6; 95% CI, 7.7–72.4), multiple previous TB episodes (odds ratio, 15.6; 95% CI, 5.0–49.1), and cavities present on chest radiograph (odds ratio, 5.9; 95% CI, 1.2–29.5). Among a cohort of 250 patients, 5.2% (95% CI, 2.8%–8.7%) were infected with M. tuberculosis that developed additional drug resistance. Amplification of drug resistance was associated with existing drug resistance at baseline (P ! .01) and delayed sputum culture conversion (P ! .01). Conclusions. The burden of drug resistance in previously treated patients with TB in Uganda is sizeable, and the risk of generating additional drug resistance is significant. There is an urgent need to improve the treatment for such patients in low-income countries.
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    Treatment Outcomes of New Tuberculosis Patients Hospitalized in Kampala, Uganda: A Prospective Cohort Study
    (PLoS ONE, 2014) Kirenga, Bruce J.; Levin, Jonathan; Ayakaka, Irene; Worodria, William; Reilly, Nancy; Mumbowa, Francis; Nabanjja, Helen; Nyakoojo, Grace; Fennelly, Kevin; Nakubulwa, Susan; Joloba, Moses; Okwera, Alphonse; Eisenach, Kathleen D.; McNerney, Ruth; Elliott, Alison M.; Mugerwa, Roy D.; Smith, Peter G.; Ellner, Jerrold J.; Jones-Lopez, Edward C.
    In most resource limited settings, new tuberculosis (TB) patients are usually treated as outpatients. We sought to investigate the reasons for hospitalisation and the predictors of poor treatment outcomes and mortality in a cohort of hospitalized new TB patients in Kampala, Uganda Methods and findings: Ninety-six new TB patients hospitalised between 2003 and 2006 were enrolled and followed for two years. Thirty two were HIV-uninfected and 64 were HIV-infected. Among the HIV-uninfected, the commonest reasons for hospitalization were low Karnofsky score (47%) and need for diagnostic evaluation (25%). HIV-infected patients were commonly hospitalized due to low Karnofsky score (72%), concurrent illness (16%) and diagnostic evaluation (14%). Eleven HIV uninfected patients died (mortality rate 19.7 per 100 person-years) while 41 deaths occurred among the HIV-infected patients (mortality rate 46.9 per 100 person years). In all patients an unsuccessful treatment outcome (treatment failure, death during the treatment period or an unknown outcome) was associated with duration of TB symptoms, with the odds of an unsuccessful outcome decreasing with increasing duration. Among HIV-infected patients, an unsuccessful treatment outcome was also associated with male sex (P = 0.004) and age (P = 0.034). Low Karnofsky score (aHR = 8.93, 95% CI 1.88 – 42.40, P = 0.001) was the only factor significantly associated with mortality among the HIV-uninfected. Mortality among the HIV-infected was associated with the composite variable of CD4 and ART use, with patients with baseline CD4 below 200 cells/mL who were not on ART at a greater risk of death than those who were on ART, and low Karnofsky score (aHR = 2.02, 95% CI 1.02 – 4.01, P = 0.045). Conclusion: Poor health status is a common cause of hospitalisation for new TB patients. Mortality in this study was very high and associated with advanced HIV Disease and no use of ART.