Browsing by Subject "History of tuberculosis"

Now showing 1 - 7 of 7
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    Assessment at antiretroviral clinics during TB treatment reduces loss to follow-up among HIV-infected patients
    (Public Library of Science, 2012) Pepper, Dominique J; Marais, Suzaan; Bhaijee, Feriyl; Wilkinson, Robert J; De Azevedo, Virginia; Meintjes, Graeme
    Setting: A South African township clinic where loss to follow-up during TB treatment may prevent HIV-infected TB patients from receiving life-saving ART. Objective: To determine factors associated with loss to follow-up during TB treatment. Design: Regression analyses of a cohort of ART-eligible TB patients who commenced TB treatment and were followed for 24 weeks. RESULTS: Of 111 ART-eligible TB patients, 15 (14%) died in the ensuing 24 weeks. Of the remaining 96 TB patients, 11 (11%) were lost to follow-up. All TB patients lost to follow-up did not initiate ART. Of 85 TB patients in follow-up, 62 (73%) initiated ART 56 days after TB diagnosis (median, IQR 33-77 days) and 31 days after initial assessment at an ART clinic (median, IQR: 18-55 days). The median duration from TB diagnosis to initial assessment at an ART clinic was 19 days (IQR: 7-48 days). At 24 weeks, 6 of 85 (7%) TB patients who presented to an ART clinic for assessment were lost to follow-up, compared to 5 of 11 (45%) TB patients who did not present to an ART clinic for assessment. Logistic regression analysis (adjusted odds ratio  = 0.1, 95% confidence interval [95% CI]: 0.03-0.66) and our Cox proportional hazards model (hazard ratio  = 0.2, 95% CI: 0.04-0.68) confirmed that assessment at an ART clinic during TB treatment reduced loss to follow-up. CONCLUSION: Assessment at antiretroviral clinics for HIV care by trained health-care providers reduces loss to follow-up among HIV-infected patients with TB.
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    Barriers to initiation of antiretrovirals during antituberculosis therapy in Africa
    (Public Library of Science, 2011) Pepper, Dominique J; Marais, Suzaan; Wilkinson, Robert J; Bhaijee, Feriyl; De Azevedo, Virginia; Meintjes, Graeme
    BACKGROUND: In the developing world, the principal cause of death among HIV-infected patients is tuberculosis (TB). The initiation of antiretroviral therapy (ART) during TB therapy significantly improves survival, however it is not known which barriers prevent eligible TB patients from initiating life-saving ART. Method Setting. A South African township clinic with integrated tuberculosis and HIV services. Design. Logistic regression analyses of a prospective cohort of HIV-1 infected adults (≥18 years) who commenced TB therapy, were eligible for ART, and were followed for 6 months. FINDINGS: Of 100 HIV-1 infected adults eligible for ART during TB therapy, 90 TB patients presented to an ART clinic for assessment, 66 TB patients initiated ART, and 15 TB patients died. 34% of eligible TB patients (95%CI: 25-43%) did not initiate ART. Male gender and younger age (<36 years) were associated with failure to initiate ART (adjusted odds ratios of 3.7 [95%CI: 1.25-10.95] and 3.3 [95%CI: 1.12-9.69], respectively). Death during TB therapy was associated with a CD4+ count <100 cells/µL. CONCLUSION: In a clinic with integrated services for tuberculosis and HIV, one-third of eligible TB patients - particularly young men - did not initiate ART. Strategies are needed to promote ART initiation during TB therapy, especially among young men.
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    Burden of new and recurrent tuberculosis in a major South African city stratified by age and HIV-status
    (Public Library of Science, 2011) Wood, Robin; Lawn, Stephen D; Caldwell, Judy; Kaplan, Richard; Middelkoop, Keren; Bekker, Linda-Gail
    Aim: To describe the burden of tuberculosis (TB) in Cape Town by calculating TB incidence rates stratified by age and HIV-status, assessing the contribution of retreatment disease and estimating the cumulative lifetime TB risk in HIV-negative individuals. METHODS: Details of TB cases were abstracted from the 2009 electronic TB register. Population denominators were estimated from census data and actuarial estimates of HIV prevalence, allowing calculation of age-specific and HIV-stratified TB notification rates. RESULTS: The 2009 mid-year population was 3,443,010 (3,241,508 HIV-negative and 201,502 HIV-positive individuals). There were 29,478 newly notified TB cases of which 56% were laboratory confirmed. HIV status was recorded for 87% of cases and of those with known HIV-status 49% were HIV-negative and 51% were positive. Discrete peaks in the incidence of non-HIV-associated TB occurred at three ages: 511/100,000 at 0-4 years of age, 553/100,000 at 20-24 years and 628/100,000 at 45-49 years with 1.5%, 19% and 45% being due to retreatment TB, respectively. Only 15.5% of recurrent cases had a history of TB treatment failure or default. The cumulative lifetime risks in the HIV-negative population of all new TB episodes and new smear-positive TB episodes were 24% and 12%, respectively; the lifetime risk of retreatment disease was 9%. The HIV-positive notification rate was 6,567/100,000 (HIV-associated TB rate ratio = 17). Although retreatment cases comprised 30% of the HIV-associated TB burden, 88% of these patients had no history of prior treatment failure or default. CONCLUSIONS: The annual burden of TB in this city is huge. TB in the HIV-negative population contributed almost half of the overall disease burden and cumulative lifetime risks were similar to those reported in the pre-chemotherapy era. Retreatment TB contributed significantly to both HIV-associated and non-HIV-associated TB but infrequently followed prior inadequate treatment. This likely reflects ongoing TB transmission to both HIV-negative and positive individuals.
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    A century of tuberculosis epidemiology in the northern and southern hemisphere: the differential impact of control interventions
    (Public Library of Science, 2015) Hermans, Sabine; Jr, C Robert Horsburgh; Wood, Robin
    BACKGROUND: Cape Town has one of the highest TB burdens of any city in the world. In 1900 the City of Cape Town, New York City and London had high mortality of tuberculosis (TB). Throughout the 20th century contemporaneous public health measures including screening, diagnosis and treatment were implemented in all three settings. Mandatory notification of TB and vital status enabled comparison of disease burden trajectories. METHODS: TB mortality, notification and case fatality rates were calculated from 1912 to 2012 using annual TB notifications, TB death certifications and population estimates. Notification rates were stratified by age and in Cape Town by HIV status (from 2009 onwards). RESULTS: Pre-chemotherapy, TB mortality and notification rates declined steadily in New York and London but remained high in Cape Town. Following introduction of combination chemotherapy, mean annual case fatality dropped from 45-60% to below 10% in all three settings. Mortality and notification rates subsequently declined, although Cape Town notifications did not decline as far as those in New York or London and returned to pre-chemotherapy levels by 1980. The proportional contribution of childhood TB diminished in New York and London but remained high in Cape Town. The advent of the Cape Town HIV-epidemic in the 1990s was associated with a further two-fold increase in incidence. In 2012, notification rates among HIV-negatives remained at pre-chemotherapy levels. CONCLUSIONS: TB control was achieved in New York and London but failed in Cape Town. The TB disease burden trajectories started diverging before the availability of combination chemotherapy in 1952 and further diverged following the HIV epidemic in 1990. Chemotherapy impacted case fatality but not transmission, evidenced by on-going high childhood TB rates. Currently endemic TB results from high on-going transmission, which has been exacerbated by the HIV epidemic. TB control will require reducing transmission, which is inexorably linked to prevailing socio-economic factors.
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    Presentation and outcome of tuberculous meningitis in a high HIV prevalence setting
    (Public Library of Science, 2011) Marais, Suzaan; Pepper, Dominique J; Schutz, Charlotte; Wilkinson, Robert J; Meintjes, Graeme
    BACKGROUND: Mycobacterium tuberculosis is a common, devastating cause of meningitis in HIV-infected persons. Due to international rollout programs, access to antiretroviral therapy (ART) is increasing globally. Starting patients with HIV-associated tuberculous meningitis (TBM) on ART during tuberculosis (TB) treatment may increase survival in these patients. We undertook this study to describe causes of meningitis at a secondary-level hospital in a high HIV/TB co-infection setting and to determine predictors of mortality in patients with TBM. METHODS: A retrospective review of cerebrospinal fluid findings and clinical records over a six-month period (March 2009-August 2009). Definite, probable and possible TBM were diagnosed according to published case definitions. RESULTS: TBM was diagnosed in 120/211 patients (57%) with meningitis. In 106 HIV-infected patients with TBM, six-month all-cause mortality was lower in those who received antiretroviral therapy (ART) during TB treatment; hazard ratio = 0.30 (95% CI = 0.08-0.82). Factors associated with inpatient mortality in HIV-infected patients were 1) low CD4 + count at presentation; adjusted odds ratio (AOR) = 1.4 (95% confidence interval [CI] = 1.03-1.96) per 50 cells/µL drop in CD4 + count and, 2) higher British Medical Research Council TBM disease grade (2 or 3 versus 1); AOR = 4.8 (95% CI = 1.45-15.87). Interpretation Starting ART prior to or during TB treatment may be associated with lower mortality in patients with HIV-associated TBM. Advanced HIV and worse stage of TBM disease predict in-hospital mortality in patients presenting with TBM.
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    Prevalent and incident tuberculosis are independent risk factors for mortality among patients accessing antiretroviral therapy in South Africa
    (Public Library of Science, 2013) Gupta, Ankur; Wood, Robin; Kaplan, Richard; Bekker, Linda-Gail; Lawn, Stephen D
    BACKGROUND: Patients with prevalent or incident tuberculosis (TB) in antiretroviral treatment (ART) programmes in sub-Saharan Africa have high mortality risk. However, published data are contradictory as to whether TB is a risk factor for mortality that is independent of CD4 cell counts and other patient characteristics. Methods/FINDINGS: This observational ART cohort study was based in Cape Town, South Africa. Deaths from all causes were ascertained among patients receiving ART for up to 8 years. TB diagnoses and 4-monthly CD4 cell counts were recorded. Mortality rates were calculated and Poisson regression models were used to calculate incidence rate ratios (IRR) and identify risk factors for mortality. Of 1544 patients starting ART, 464 patients had prevalent TB at baseline and 424 developed incident TB during a median of 5.0 years follow-up. Most TB diagnoses (73.6%) were culture-confirmed. A total of 208 (13.5%) patients died during ART and mortality rates were 8.84 deaths/100 person-years during the first year of ART and decreased to 1.14 deaths/100 person-years after 5 years. In multivariate analyses adjusted for baseline and time-updated risk factors, both prevalent and incident TB were independent risk factors for mortality (IRR 1.7 [95% CI, 1.2-2.3] and 2.7 [95% CI, 1.9-3.8], respectively). Adjusted mortality risks were higher in the first 6 months of ART for those with prevalent TB at baseline (IRR 2.33; 95% CI, 1.5-3.5) and within the 6 months following diagnoses of incident TB (IRR 3.8; 95% CI, 2.6-5.7). CONCLUSIONS: Prevalent TB at baseline and incident TB during ART were strongly associated with increased mortality risk. This effect was time-dependent, suggesting that TB and mortality are likely to be causally related and that TB is not simply an epiphenomenon among highly immunocompromised patients. Strategies to rapidly diagnose, treat and prevent TB prior to and during ART urgently need to be implemented.
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    The tuberculin skin test versus QuantiFERON TB Gold® in predicting tuberculosis disease in an adolescent cohort study in South Africa
    (Public Library of Science, 2011) Mahomed, Hassan; Hawkridge, Tony; Verver, Suzanne; Abrahams, Deborah; Geiter, Lawrence; Hatherill, Mark; Ehrlich, Rodney; Hanekom, Willem A; Hussey, Gregory D
    Setting This study was conducted in a high tuberculosis (TB) burden area in Worcester, South Africa, with a notified all TB incidence rate of 1,400/100,000. Main Objective To compare the predictive value of a baseline tuberculin skin test (TST) with that of the QuantiFERON TB Gold (In-tube) assay (QFT) for subsequent microbiologically confirmed TB disease among adolescents. METHODS: Adolescents aged 12-18 years were recruited from high schools in the study area. At baseline, blood was drawn for QFT and a TST administered. Participants were followed up for up to 3.8 years for incident TB disease (median 2.4 years). RESULTS: After exclusions, 5244 (82.4%) of 6,363 adolescents enrolled, were analysed. The TB incidence rate was 0.60 cases per 100 person years (pyrs) (95% CI 0.43-0.82) for baseline TST positive (≥5 mm) participants and 0.64 cases per 100 pyrs (95% CI 0.45-0.87) for baseline QFT positive participants. TB incidence rates were 0.22 per 100 pyrs (0.11-0.39) and 0.22 per 100 pyrs (0.12-0.38) among those with a negative baseline TST and QFT respectively. Sensitivity for incident TB disease was 76.9% for TST and 75.0% for QFT (p = 0.81). Positive predictive value was 1.4% for TST and 1.5% for QFT. CONCLUSION: Positive TST and QFT tests were moderately sensitive predictors of progression to microbiologically confirmed TB disease. There was no significant difference in the predictive ability of these tests for TB disease amongst adolescents in this high burden setting. Therefore, these findings do not support use of QFT in preference to TST to predict the risk of TB disease in this study population.