Search results for "Latent tuberculosi"
showing 10 items of 22 documents
Prediabetes is associated with the modulation of antigen-specific Th1/Tc1 and Th17/Tc17 responses in latent Mycobacterium tuberculosis infection.
2017
Type 2 diabetes mellitus (DM) is associated with the down modulation of Th1, Th2 and Th17 responses in latent Mycobacterium tuberculosis infection but the role of prediabetes (PDM) in this setting is not well understood. To examine the role of CD4+ and CD8+ T cell cytokines in latent tuberculosis (LTB) with coincident PDM, we studied the baseline, mycobacterial, control antigen and mitogen-stimulated T cell cytokine responses in LTB individuals with (LTB-PDM; n = 20) or without (LTB-NDM; n = 20) concomitant prediabetes. LTB-PDM is characterized by diminished frequencies of mono-and dual-functional CD4+ Th1 and Th17 cells and mono-functional Th2 cells at baseline and/or following mycobacteri…
Identification of plasma biomarkers for discrimination between tuberculosis infection/disease and pulmonary non tuberculosis disease.
2018
We used the Luminex Bead Array Multiplex Immunoassay to measure cytokines, chemokines and growth factors responses to the same antigens used for RD1-based Interferon γ Release Assay (IGRA) test. Seventy-nine individuals, 27 active TB, 32 latent infection subsets, 20 individuals derivative purified protein (PPD) negative (subjects that do not have any indurative cutaneous reaction after 72 hrs of intradermal injection of PPD) and with other pulmonary disease were retrospectively studied. Forty-eight analytes were evaluated by Luminex Assay in plasma obtained from whole blood stimulated cells. The diagnostic accuracies of the markers detected were evaluated by ROC curve analysis and by the co…
The Role of Laboratory Tests in Crohn's Disease.
2016
In the past, laboratory tests were considered of limited value in Crohn's disease (CD). In the era of biologics, laboratory tests have become essential to evaluate the inflammatory burden of the disease (C-reactive protein, fecal calprotectin) since symptoms-based scores are subjective, to predict the response to pharmacological options and the risk of relapse, to discriminate CD from ulcerative colitis, to select candidates to anti-tumor necrosis factors [screening tests looking for hepatitis B virus and hepatitis C virus status and latent tuberculosis], to assess the risk of adverse events (testing for thiopurine metabolites and thiopurine-methyltransferase activity), and to personalize a…
Screening for Latent Tuberculosis Infection among Students of Healthcare Professions and Postgraduates of the Faculty of Medicine of the University o…
2017
Introduction and objective: Italy is a country with a low incidence of tuberculosis and in the last fifty years the annual number of TB cases decreased from 12,247 to 4,418, showing a reduction of approximately 64% in the number of cases and 71% in incidence. Despite of this encouraging trend, in the last years the epidemiology of tuberculosis changed and today it is a re-emerging infectious. The aim of this study is to measure the prevalence of positivity to tuberculosis infection (latent TB) in students, without any obvious manifestation of disease, attending degree courses of the health care professions and postgraduate medical courses of the School of Medicine of the University of Paler…
Human CD4 T-Cells With a Naive Phenotype Produce Multiple Cytokines During Mycobacterium Tuberculosis Infection and Correlate With Active Disease
2018
T-cell-mediated immune responses play a fundamental role in controlling Mycobacterium tuberculosis (M. tuberculosis) infection, and traditionally, this response is thought to be mediated by Th1-type CD4+ T-cells secreting IFN-γ. While studying the function and specificity of M. tuberculosis-reactive CD4+ T-cells in more detail at the single cell level; however, we found a human CD4+ T-cell population with a naive phenotype that interestingly was capable of producing multiple cytokines (TCNP cells). CD4+ TCNP cells phenotyped as CD95lo CD28int CD49dhi CXCR3hi and showed a broad distribution of T cell receptor Vβ segments. They rapidly secreted multiple cytokines in response to different M. t…
Granzyme A as a potential biomarker of Mycobacterium tuberculosis infection and disease
2015
Cytotoxic molecules such as granulysin, perforin and granzymes produced by cytolytic T cells directly contribute to immune defense against tuberculosis (TB). In search for novel TB biomarkers, we have evaluated the levels of granzyme A in plasma obtained from QuantiFERON-TB Gold In tube (QFT-IT) assays from patients with active TB disease and subjects with latent TB infection (LTBI).Granzyme A serum levels in TB patients were significantly lower than values found in LTBI subjects even after subtraction of the unstimulated levels from the antigen-stimulated responses. The receiver operator characteristics (ROC) curve analysis comparing TB patients and LTBI groups, showed that at a cut-off va…
Latent Tuberculosis Infection among Healthcare Students and Postgraduates in a Mediterranean Italian Area: What Correlation with Work Exposure?
2019
Background: Tuberculosis screening is part of the standard protocol for evaluating the risk of infection in healthcare workers. The aim of this study was to evaluate the prevalence of latent tuberculosis infection (LTBI) among students attending various healthcare profession degree courses and postgraduate medical courses at the School of Medicine of the University of Palermo, Italy, and assess the possible professional origin of infection. Methods: In total, 2946 students (2082 undergraduates and 864 postgraduates) took part in a screening program for LTBI between January 2014 to April 2019 using the tuberculin skin test (TST). Students with a positive TST result underwent a Quantiferon-TB…
New tools for detecting latent tuberculosis infection: evaluation of RD1-specific long-term response
2009
Abstract Background Interferon-gamma (IFN-γ) release assays (IGRAs) were designed to detect latent tuberculosis infection (LTBI). However, discrepancies were found between the tuberculin skin test (TST) and IGRAs results that cannot be attributed to prior Bacille Calmètte Guerin vaccinations. The aim of this study was to evaluate tools for improving LTBI diagnosis by analyzing the IFN-γ response to RD1 proteins in prolonged (long-term response) whole blood tests in those subjects resulting negative to assays such as QuantiFERON-TB Gold In tube (QFT-IT). Methods The study population included 106 healthy TST+ individuals with suspected LTBI (recent contact of smear-positive TB and homeless) c…
Novel M. tuberculosis specific IL-2 ELISpot assay discriminates adult patients with active or latent tuberculosis
2018
Background Tuberculosis (TB) still is a major worldwide health problem, with 10.4 million new cases in 2016. Only 5–15% of people infected with M. tuberculosis develop TB disease while others remain latently infected (LTBI) during their lifetime. Thus, the absence of tests able to distinguish between latent infection and active tuberculosis is one of the major limits of currently available diagnostic tools. Methods A total of 215 patients were included in the study as active TB cases (n = 73), LTBI subjects (n = 88) and healthy persons (n = 54). Peripheral blood mononuclear cells (PBMCs) were isolated from each patient and the LIOSpot® TB anti-human IL-2 ELISpot assay was performed to test …
Performance of QuantiFERON-TB Gold Plus for detection of latent tuberculosis infection in pregnant women living in a tuberculosis- and HIV-endemic se…
2017
We evaluated the performance of QuantiFERON-TB Gold Plus (QFT-Plus), which includes two Mycobacterium tuberculosis antigen formulations (TB1 and TB2), for detection of latent tuberculosis infection during pregnancy. Eight-hundred-twenty-nine Ethiopian pregnant women (5.9% HIV-positive) were tested with QFT-Plus, with bacteriological sputum analysis performed for women with clinically suspected tuberculosis and HIV-positive women irrespective of clinical presentation. QFT-Plus read-out was categorized according to the conventional cut-off (0.35 IU/ml) for both antigen formulations. In addition, we analysed the distribution of QFT-Plus results within a borderline zone (0.20–0.70 IU/ml), and i…