Active clinical trials for "Latent Tuberculosis"

Clinical test (essay) randomized to evaluate the toxicity adherence and efficiency of the chemoprophylaxis of tuberculosis (TB) in subjects with Diabetes Mellitus (DM) and latent TB. (600 subjects followed(continued) by 15 months). 3rd stage. Patients with DM and TB will be included to determine if the strict control of the dm achieved in clinics of the first level of attention improves clinical manifestations of tb, the result of treatment, the frequency of relapses, the mortality and the transmission to contacts. Elispot will be used to measure TB development and the time for the bacteriological negativization and biochemical parameters as well as tuberculin skin test (TST), quantiferon, in contacts. (160 patients 600 contacts followed(continued) for 12 months). additional there will be evaluated the socioeconomic impact of both diseases and his(her) control. 1er year: transverse study and recruitment years 2 and 3 participants' follow-ups in clinical tests(essays).

This study will examine the impact of use of mobile phones and text messaging on adherence to treatment for patients with latent TB infection. Half (50%) of the 350 anticipated study participants will receive weekly text messages inquiring on their health status in relation to their prescribed treatment, while the other half (50%) will not receive weekly text messages at all. Medical adherence will be assessed by monthly blood-work, clinic visits and by interviewing patients at each of these visits. The investigators hypothesis is that enhanced communication with a health care provider, via a structured cell phone SMS text messaging based program (WelTel), will result in a 15% improvement in the proportion of patients who successfully complete their LTBI treatment regimens.

Center for Disease Control (CDC) data reveal that after years of sustained decrease, the incidence of active tuberculosis (TB) disease in the US has plateaued. Most of the cases occur when Mycobacterium tuberculosis (Mtb) reactivates replication in people who have latent tuberculosis infection (LTBI). Only 5 to 10% of subjects with LTBI develop active TB Infection over their lifetime. Current US guidelines recommend treating everyone with LTBI to stop progression to active TB. As treatment is long, only about 45-55% of patients finish treatment overall, regardless of whether the patients are at high (>10%) or low lifetime risk of reactivation. The investigator's study aims to test the efficacy of a combined approach of first determining subjects at high risk of reactivation and then treating them with a CDC approved once a week treatment regimen, directly observed by a nurse over video (video-based Directly Observed Therapy, vDOT). Ensuring treatment of the high-risk group will eventually decrease the community active TB burden.

To compare the positivity rate of the investigational assay to the currently approved QuantiFERON-TB Gold In-Tube assay.

In countries with a low incidence of Tuberculosis (TB), the incidence remains higher among the immigrant population than among the autochthonous population beyond the first years after arrival in the host country. In addition, at a pediatric level, most cases are produced in immigrant children and the children of immigrants. This persistence of a greater incidence in the immigrant population might, in part, be explained by the increase in exposure to Mycobacterium tuberculosis during trips to their country of origin to visit friends and relatives (VFRs). The objectives of the study are to estimate the risk of latent infection by M. tuberculosis (LTBI)/TB in children VFRs and the factors associated with this risk. The investigators will also study the behavior of the diagnostic tests. This project will be carried out in collaboration with 21 primary health care centers and 5 hospitals in Catalonia.

Tuberculosis is still the most common infectious disease in Taiwan. The infants in Taiwan have been vaccinated at birth with BCG -Tokyo 171 strain since 1951. The BCG vaccination rate is 97% among first grade students in a recent national survey. Even with such a high BCG vaccination coverage, Taiwan still has a relatively high TB incidence rate. In 2004, there were totally 16,784 newly diagnosed TB cases and the annual incidence was 74.11 per 100,000 population nationally. Nearly 70% of the incidence cases were men and 30.4% were women. The mean age of incidence cases was 57.8 years old (median=63). 8,440(50.29%) patients were elderly than 65 years old. The elderly men did not receive the BCG vaccination and were the most important group to develop newly diagnosed tuberculosis and a special issue for the national TB control program in Taiwan. The tuberculin skin test (TST) is the only widely available method for detecting whether people have an immunologic reactivity to mycobacterial antigens and identified as latent tuberculosis infection (LTBI). Targeted tuberculin testing for latent TB infection is a very important strategy to identify subjects with high risk to develop tuberculosis including those who have recent infection with Mycobacterium tuberculosis or have clinical conditions that associated with an increased risk for progression of LTBI to active TB but the sensitivity was lower in elderly patients. Quantiferon-TB gold test (QFT-RD1) is a new diagnostic test for latent tuberculosis and a valuable alternative to skin testing. This whole-blood assay measures the production of IFN-  in whole blood upon stimulation by ESAT-6 and CFP-10 and allows distinction of latent M. tuberculosis infection from BCG-induced reactivity. ESAT-6 and CFP-10 are deleted from BCG Region 1 (RD1), not present in most nontuberculous mycobacteria and are highly specific indicators of M. tuberculosis infection. Thus, the aim of this study was to estimate the specificity and sensitivity of a whole blood IFN-γassay employing CFP-10 and ESAT-6, for the detection of M. tuberculosis infection in a clustered high risk elderly population. Changhwa Veterans Home is a government-expense veterans home with totally 519 residents in 2004.The inhabitants were all elderly people and lived in groups. , They did not receive BCG vaccination and were the high risk group to develop endemic TB infection. The annual TB incidence rate over there was 3,500 per 100,000 population.

The purpose of this study is to determine of once identified to the subjects infected with human immunodeficiency virus (positive VIH), to diagnose latent Tuberculosis, and to treat her with isoniazid for six months, measuring the production of Interferon range pre and posttreatment, to evaluate this way the result of the treatment on the immune response

Interferon gamma release assays (IGRA) have been shown to be more specific and sensitive for the detection of tuberculosis (latent or active infection) than the tuberculin skin test (TST) in immunocompetent individuals. However, very little data are available concerning the relative performance of IGRA and TST in immunosuppressed individuals from other causes than HIV. The investigators hypothesize that IGRAs would be more sensitive and specific than the TST in a group of renal transplant recipients under chronic immunosuppressive treatment for detecting latent tuberculosis infection.

This is a prospective cohort study of persons tested for latent tuberculosis infection at either high risk for exposure to Mycobacterium tuberculosis or high risk for progression to tuberculosis disease. The study will assess the relative performance and cost of three diagnostic tests for latent tuberculosis infection (tuberculin skin test, QuantiFERON-TB Gold In-Tube, and T-SPOT.TB) and will examine the rates of positive results among the cohort. This study will also determine the risk and rate of progression to active TB disease, overall and by the results of the three tests.

Study the prevalence of LTBI in patients who are waiting renal transplant and monitor the incidence of active TB