23 research outputs found
Acquired rifampicin resistance in thrice-weekly antituberculosis therapy: impact of HIV and antiretroviral therapy
Risk factors for acquired rifampicin resistance (ARR) among tuberculosis patients on thrice-weekly antituberculosis therapy were baseline isoniazid resistance and HIV. Among HIV-infected patients, higher mycobacterial burden and lower CD4 count, but not highly active antiretroviral therapy, were significantly associated with ARR. Background: Risk factors for acquired rifampicin resistance (ARR) in human immunodeficiency virus (HIV)/tuberculosis coinfection, in the highly active antiretroviral therapy (HAART) era, needs evaluation. We studied the impact of HIV and HAART on ARR among patients taking thrice-weekly antituberculosis therapy. Methods: This cross-protocol analysis included patients with newly diagnosed, rifampicin-susceptible pulmonary tuberculosis, with and without HIV, enrolled in clinical trials (who took >80% of medication) at the National Institute for Research in Tuberculosis between 1999 and 2013. All patients received rifampicin and isoniazid for 6 months reinforced with pyrazinamide and ethambutol in the first 2 months, given thrice-weekly throughout the study along with HAART in one of the groups. Outcomes were categorized and multivariate logistic regression analysis performed to identify risk factors for ARR. Results: The per-protocol results included patients with tuberculosis: 246 HIV-uninfected patients (HIVâTB+), 212 HIV patients not on HAART (non-HAART), and 116 HIV-infected patients on HAART. Median CD4 counts of the latter 2 groups were 150 and 93 cells/μL, respectively, and the median viral loads were 147 000 and 266 000 copies/mL, respectively. Compared with HIVâTB+, the relative risks (RRs) for an unfavorable response in the coinfected, non-HAART and HAART groups were 2.1 (95% confidence interval [CI], 1.7â14.8; P<.0001) and 2.1 (95% CI, .9â5.2; P=.3), whereas for ARR, the RRs were 21.1 (95% CI, 2.6â184; P<.001) and 8.2 (95% CI, .6â104; P=.07), respectively. Conclusions: HIV-infected patients with tuberculosis treated with a thrice-weekly antituberculosis regimen are at a higher risk of ARR, compared with HIV-uninfected patients, in the presence of baseline isoniazid resistance. HAART reduces but does not eliminate the risk of ARR
Paradoxical tuberculosis immune reconstitution inflammatory syndrome (TB-IRIS) in HIV patients with culture confirmed pulmonary tuberculosis in India and the potential role of IL-6 in prediction
Background: The incidence, manifestations, outcome and clinical predictors of paradoxical TB-IRIS in patients with HIV and culture confirmed pulmonary tuberculosis (PTB) in India have not been studied prospectively. Methods: HIV+ patients with culture confirmed PTB started on anti-tuberculosis therapy (ATT) were followed prospectively after anti-retroviral therapy (ART) initiation. Established criteria for IRIS diagnosis were used including decline in plasma HIV RNA at IRIS event. Pre-ART plasma levels of interleukin (IL)-6 and C-reactive protein (CRP) were measured. Univariate and multivariate logistic regression models were used to evaluate associations between baseline variables and IRIS. Results: Of 57 patients enrolled, 48 had complete follow up data. Median ATT-ART interval was 28 days (interquartile range, IQR 14â47). IRIS events occurred in 26 patients (54.2%) at a median of 11 days (IQR: 7â16) after ART initiation. Corticosteroids were required for treatment of most IRIS events that resolved within a median of 13 days (IQR: 9â23). Two patients died due to CNS TB-IRIS. Lower CD4+ T-cell counts, higher plasma HIV RNA levels, lower CD4/CD8 ratio, lower hemoglobin, shorter ATT to ART interval, extra-pulmonary or miliary TB and higher plasma IL-6 and CRP levels at baseline were associated with paradoxical TB-IRIS in the univariate analysis. Shorter ATT to ART interval, lower hemoglobin and higher IL-6 and CRP levels remained significant in the multivariate analysis. Conclusion: Paradoxical TBâIRIS frequently complicates HIV-TB therapy in India. IL-6 and CRP may assist in predicting IRIS events and serve as potential targets for immune interventions
Rhegmatogenous retinal detachment in Scotland: research design and methodology
<p>Abstract</p> <p>Background</p> <p>Rhegmatogenous retinal detachment (RRD) is a potentially blinding condition and a common cause of ocular morbidity. Establishing an accurate estimate of disease incidence and distribution is an important first step in assessing the healthcare burden related to this condition and in subsequent planning and provision of treatment strategies. The aim of this study is to obtain a first estimate incidence of RRD in Scotland, to estimate the incidence of familial RRD and to describe the known associations of RRD within the study population.</p> <p>Methods/Design</p> <p>We have established a national prospective observational study seeking to identify and recruit all incident cases of RRD in the Scottish population over a 2 year period. After fully informed consent, all participants will have a blood sample taken and a full medical history and clinical examination performed including visual acuity, refraction, slit-lamp examination, intra-ocular pressure measurement and detailed fundal examination. We describe the study design and protocol.</p> <p>Conclusion</p> <p>This study will provide the first estimate of the annual incidence of RRD in Scotland. The findings of this study will be important in estimating the burden of disease and in the planning of future health care policy related to this condition. This study will also establish a genetic resource for a genome wide association study to investigate if certain genetic variants predispose to RRD.</p
Dynamics of T-Lymphocyte Activation Related to Paradoxical Tuberculosis-Associated Immune Reconstitution Inflammatory Syndrome in Persons With Advanced HIV
Most persons living with HIV (PLWH) experience a significant restoration of their immunity associated with successful inhibition of viral replication after antiretroviral therapy (ART) initiation. Nevertheless, with the robust quantitative and qualitative restoration of CD4(+) T-lymphocytes, a fraction of patients co-infected with tuberculosis develop immune reconstitution inflammatory syndrome (TB-IRIS), a dysregulated inflammatory response that can be associated with significant tissue damage. Several studies underscored the role of adaptive immune cells in IRIS pathogenesis, but to what degree T lymphocyte activation contributes to TB-IRIS development remains largely elusive. Here, we sought to dissect the phenotypic landscape of T lymphocyte activation in PLWH coinfected with TB inititating ART, focusing on characterization of the profiles linked to development of TB-IRIS. We confirmed previous observations demonstrating that TB-IRIS individuals display pronounced CD4(+) lymphopenia prior to ART initiation. Additionally, we found an ART-induced increase in T lymphocyte activation, proliferation and cytotoxicity among TB-IRIS patients. Importantly, we demonstrate that TB-IRIS subjects display higher frequencies of cytotoxic CD8(+) T lymphocytes which is not affected by ART. Moreover, These patients exhibit higher levels of activated (HLA-DR(+)) and profilerative (Ki-67(+)) CD4(+) T cells after ART commencenment than their Non-IRIS counterparts. Our network analysis reveal significant negative correlations between Total CD4(+) T cells counts and the frequencies of Cytotoxic CD8(+) T cells in our study population which could suggest the existance of compensatory mechanisms for Mtb-infected cells elimination in the face of severe CD4(+) T cell lymphopenia. We also investigated the correlation between T lymphocyte activation profiles and the abundance of several inflammatory molecules in plasma. We applied unsupervised machine learning techniques to predict and diagnose TB-IRIS before and during ART. Our analyses suggest that CD4(+) T cell activation markers are good TB-IRIS predictors, whereas the combination of CD4(+) and CD8(+) T cells markers are better at diagnosing TB-IRIS patients during IRIS events Overall, our findings contribute to a more refined understanding of immunological mechanisms in TB-IRIS pathogenesis that may assist in new diagnostic tools and more targeted patient management
Daily vs Intermittent Antituberculosis Therapy for Pulmonary Tuberculosis in Patients With HIV
Predictors of unfavorable responses to therapy in rifampicin-sensitive pulmonary tuberculosis using an integrated approach of radiological presentation and sputum mycobacterial burden
INTRODUCTION: Despite the exalted status of sputum mycobacterial load for gauging pulmonary tuberculosis treatment and progress, Chest X-rays supplement valuable information for taking instantaneous therapeutic decisions, especially during the COVID-19 pandemic. Even though literature on individual parameters is overwhelming, few studies have explored the interaction between radiographic parameters denoting severity with mycobacterial burden signifying infectivity. By using a sophisticated approach of integrating Chest X-ray parameters with sputum mycobacterial characteristics, evaluated at all the three crucial time points of TB treatment namely pre-treatment, end of intensive phase and completion of treatment, utilizing the interactive Cox Proportional Hazards model, we aimed to precisely deduce predictors of unfavorable response to TB treatment. MATERIALS AND METHOD: We extracted de-identified data from well characterized clinical trial cohorts that recruited rifampicin-sensitive Pulmonary TB patients without any comorbidities, taking their first spell of anti-tuberculosis therapy under supervision and meticulous follow up for 24 months post treatment completion, to accurately predict TB outcomes. Radiographic data independently obtained, interpreted by two experienced pulmonologists was collated with demographic details and, sputum smear and culture grades of participants by an independent statistician and analyzed using the Cox Proportional Hazards model, to not only adjust for confounding factors including treatment effect, but also explore the interaction between radiological and bacteriological parameters for better therapeutic application. RESULTS: Of 667 TB patients with data available, cavitation, extent of involvement, lower zone involvement, smear and culture grade at baseline were significant parameters predisposing to an unfavorable TB treatment outcome in the univariate analysis. Reduction in radiological lesions in Chest X-ray by at least 50% at 2 months and 75% at the end of treatment helped in averting unfavorable responses. Smear and Culture conversion at the end of 2 months was highly significant as a predictor (p2 zones, were 3.05 (95% CI: 1.12â8.23) and 1.92 (95% CI: 0.72â5.08) respectively. Patients without cavitation, zonal involvement 2 zones and 3+ smear grade individually and independently forecasted a poorer TB outcome. The interaction model revealed that Zonal involvement confined to 2 zones, without a cavity and smear grade up to 2+, constituting âminimal diseaseâ, had a better prognosis. Radiological clearance >50% along with smear conversion at the end of intensive phase of treatment, observed to be a reasonable alternative to culture conversion in predicting a successful outcome. These parameters may potentially take up key positions as stratification factors for future trials contemplating on shorter TB regimens
Differential expression of CXCR3 and CCR6 on CD4+ T-lymphocytes with distinct memory phenotypes characterizes tuberculosis-associated immune reconstitution inflammatory syndrome
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Previous issue date: 2019-01-06Intramural Research Program of NIAID/NIH and by the Intramuralto-
India grant from the US-India Co-operative research program. This study was also financed in part by
Coordenação de Aperfeiçoamento de Pessoal de NĂvel Superior (CAPES) (Finance Code 001). The work of
B.B.A. was supported by a grant from NIH (U01AI115940). P.S.S.M. was supported by a PhD fellowship from the
Fundação de Amparo à Pesquisa do Estado da Bahia (FAPESB). K.F.F. received a fellowship from the Programa
Nacional de PĂłs-Doutorado, CAPES. C.V. and D.S. are supported by FAPESBFundação Oswaldo Cruz. Instituto Gonçalo Moniz. Salvador, BA, Brasil / Fundação JosĂ© Silveira. Multinational Organization Network Sponsoring Translational and Epidemiological Research Initiative. Salvador, BA, Brasil.National Institute for Research in Tuberculosis. Chennai, India.Fundação Oswaldo Cruz. Instituto Gonçalo Moniz. Salvador, BA, Brasil / University of California. Department of Medicine. Division of Infectious Diseases. San Diego, United States of America.Fundação Oswaldo Cruz. Instituto Gonçalo Moniz. Salvador, BA, Brasil / Fundação JosĂ© Silveira. Multinational Organization Network Sponsoring Translational and Epidemiological Research Initiative. Salvador, BA, Brasil.National Institute for Research in Tuberculosis. Chennai, India.National Institute for Research in Tuberculosis. Chennai, India.National Institute for Research in Tuberculosis. Chennai, India.National Institute for Research in Tuberculosis. Chennai, India.Fundação Oswaldo Cruz. Instituto Gonçalo Moniz. Salvador, BA, Brasil.Fundação Oswaldo Cruz. Instituto Gonçalo Moniz. Salvador, BA, Brasil.Fundação Oswaldo Cruz. Instituto Rene Rachou. LaboratĂłrio de Biologia e Imunologia de Doenças Infecciosas e ParasitĂĄrias. Belo Horizonte, MG, Brasil.Government Hospital of Thoracic Medicine. Tambaram, Chennai, India.National Institutes of Health. National Institute of Allergy and Infectious Diseases. Laboratory of Immunoregulation. Clinical HIV Pathogenesis Section. Bethesda, Maryland, United States of America.National Institutes of Health. National Institute of Allergy and Infectious Diseases. Laboratory of Parasitic Diseases. Immunobiology Section. Bethesda, Maryland, United States of America.National Institute for Research in Tuberculosis. Chennai, India.Government Hospital of Thoracic Medicine. Tambaram, Chennai, India.Fundação Oswaldo Cruz. Instituto Gonçalo Moniz. Salvador, BA, Brasil / Fundação JosĂ© Silveira. Multinational Organization Network Sponsoring Translational and Epidemiological Research Initiative. Salvador, BA, Brasil / University of Cape Town. Institute of Infectious Disease and Molecular Medicine. Wellcome Trust Centre for Infectious Disease Research in Africa. Cape Town, Republic of South Africa / Escola Bahiana de Medicina e SaĂșde PĂșblica. Salvador, BA, Brasil / Universidade Salvador. Laureate Universities. Salvador, BA, Brasil / Vanderbilt University School of Medicine. Division of Department of Medicine. Infectious Diseases. Nashville, Tennessee, United States of America.Immune reconstitution inflammatory syndrome (IRIS) occurs in up to 40% of individuals co-infected with pulmonary tuberculosis (PTB) and HIV, primarily upon antiretroviral therapy (ART) initiation. Phenotypic changes in T-cells during TB-IRIS and their relationship with systemic inflammation are not fully understood. In this prospective cohort study, we followed 48 HIV-positive patients with PTB from South India before and after ART initiation, examining T-lymphocyte subsets and inflammatory biomarkers in peripheral blood. Quantification of naĂŻve (CD27+CD45RO-) as well as effector memory CD4+ T cells (CD27-CD45RO+) at weeks 2-6 after ART initiation could distinguish TB-IRIS from non-IRIS individuals. Additional analyses revealed that ART reconstituted different quantities of CD4+ T lymphocyte subsets with preferential expansion of CXCR3+ CCR6- cells in TB-IRIS patients. Moreover, there was an expansion and functional restoration of central memory (CD27+CD45RO+) CXCR3+CCR6- CD4+ lymphocytes and corresponding cytokines, with reduction in CXCR3-CCR6+ cells after ART initiation only in those who developed TB-IRIS. Together, these observations trace a detailed picture of CD4+ T cell subsets tightly associated with IRIS, which may serve as targets for prophylactic and/or therapeutic interventions in the future
Baseline characteristics of the study population stratified by IRIS status.
<p><b>NOTE.</b> Data represent no. (%) of participants unless otherwise specified. ALT, alanine transaminase; AST, aspartate aminotransferase; ATT, anti-tuberculous treatment; EPTB, extra-pulmonary tuberculosis; IQR, interquartile range; RBC, red blood cell; TB, tuberculosis.</p