View clinical trials related to Latent Tuberculosis.
Filter by:The investigators aim to study the prevalence of latent tuberculosis infection (LTBI) using whole-blood interferon-r release assays, and determine the risk factors of LTBI in Korean health care workers.
In patients receiving long term dialysis, using new generation of QuantiFERON-TB Gold Plus can have less result variability in inter-experiment and serial follow up in comparing with QuantiFERON-TB Gold In-tube.
Study the prevalence of LTBI in patients who are waiting renal transplant and monitor the incidence of active TB
This is a multicenter, prospective observational cohort study, in which patients with chronic airway diseases including chronic obstructive pulmonary disease(COPD), asthma, asthma-COPD overlap syndrome (ACOS) will be recruited.
The purposes of this study 1. to compare the positivity of tuberculin skin test(TST) and QuantiFERON-TB Gold (QFT-G), and determine the level of agreement between two tests in patients with rheumatic diseases 2. to evaluate the difference in the occurrence of active TB in patients who receive both QFT-G and TST compared with those who receive only TST for detecting of Latent tuberculosis infection(LTBI) who are candidates of TNF inhibitors.
To follow-up the latent tuberculosis infection and evaluate the risk of developing active tuberculosis in patients with severe chronic kidney disease or receiving long-term dialysis
Background: - Tuberculosis (TB) is an infectious disease that affects numerous people worldwide. Researchers are interested in actively recruiting individuals with TB for research and treatment studies. Objectives: - To collect blood and other samples to study the natural history of tuberculosis. Eligibility: - Individuals 2 years of age and older who have either active or latent tuberculosis. Design: - Latent TB patients: Participants will have a single study visit with a physical examination and medical history, and will provide blood samples for testing. - Active TB patients: Participants will have an initial visit with a physical examination and medical history, and will provide blood samples for testing. Participants will also provide sputum samples if required, and may have an optional skin punch biopsy to collect a sample of skin tissue for study. - Treatment for active TB will be provided as part of this protocol. - Active TB participants may be asked to return for study visits every 1-2 months while receiving treatment.
It is traditionally considered that the development of Latent Tuberculosis Infection (LTBI) is due to the M. tuberculosis ability to develop a dormancy state within well-structured lesions (granulomas), which can remain in the lung of the host even for life. A new original hypothesis has been developed in the Experimental Tuberculosis Unit based on scientific evidence that take into account the idea that a lesion cannot be held forever, because the host tends to remove any lesion in order to rebuild the original parenchyma, in a healing process. Even if M. tuberculosis can remain in a dormant/non-replicating state for a long period, this is an important but not sufficient factor to explain the LTBI. The Dynamic Hypothesis tries to explain the existence of LTBI in spite of the healing process that could remove it by a constant reinfection of the host's tissue. While the "Static" view defends the induction of active TB after the reactivation of the bacilli from and old lesion; while the "Dynamic" view wants to demonstrate that there is a constant induction of new granulomas. In case one of these new lesions takes place in the upper lobe privileged zone, the possibility to induce a cavity would appear, developing an active Tuberculosis (TB).
It is traditionally considered that someone with a positive tuberculin skin test (TST) (and/or positive result in Cell Interferon-Gamma Release Assay (TIGRA), depending on the different countries' guidelines) is infected but not ill when the absence of lesions is demonstrated in a thorax X-Ray assay. Even though, the experiences described in literature using cows and pigs as animal models for the study of LTBI demonstrate the presence of this kind of lesion in the animals, even too small to be detected by X-Ray assay, which would suggest they also could happen in human LTBI. Nowadays, the High Resolution Scanners (HR TC) offer the possibility of detecting any lesion approximately 1 mm in diameter, so the investigators plan to use this technique to screen people already infected by M. tuberculosis (but not ill, following the Diagnosis Standard Guidelines). Additional pathological analysis of resected and post-mortem tissues will provide lesion-based profiles of humans infected with tuberculosis.
HIV induced altered representation and function of regulatory T cell subsets (NKT and Treg cells) impair the protective T cell response against M.tuberculosis and disrupts LTBI, thus facilitates faster progression and development of severe forms of clinical TB in HIV-TB co-infection.