Approximately 20% of persons living in areas hyperendemic for tuberculosis (TB) display persistent lack of tuberculin skin test (TST) reactivity and appear to be naturally resistant to infection by Mycobacterium tuberculosis. Among those with a positive response, the intensity of TST reactivity varies greatly. The genetic basis of TST reactivity is not known. We report on a genome-wide linkage ...

BACKGROUND Treatment of recent tuberculosis infection in children aged <2 years is essential, because of high risk of progression to disease, but diagnosis is hindered by the inaccuracy of the tuberculin skin test (TST). More-accurate T cell-based tests of infection could enhance diagnosis by optimizing interpretation of the TST results. METHODS A total of 979 child tuberculosis contacts in I...

OBJECTIVE The outcome of interest was repetition of the tuberculin skin test (TST) and the objectives were to estimate the rate of TST repetition, the probability of no TST repetition after 1 year, and the probability of no TST repetition at the end of the follow-up period in patients whose initial test was nonreactive. The study also set out to analyze factors associated with the time until TS...

SETTING Patients HIV+ attending in a reference clinic, Southern Brazil. OBJECTIVE To compare the interferon-gamma-release assay (IGRA - QuantiFERON(®) TB Gold In-Tube) with the tuberculin skin test (TST - PPD-Rt 23) for latent tuberculosis infection (LTBI) in patients with HIV. DESIGN Cohort study. Patients were simultaneously submitted to the TST and blood collection for the IGRA. RESULT...

BACKGROUND/METHODS Quantiferon-TB-Gold in Tube(®) test (QFT-G-IT) may have advantages if combined with TST when screening for Latent Tuberculosis Infection (LTBI) prior to initiating anti-TNF therapy in an area of intermediate tuberculosis incidence such as Spain. In a small-scale prospective study, we evaluate the use of QFT-G-IT in combination with the screening recommended in Spain (Tubercul...

RATIONALE Healthy household contacts (HHC) of individuals with Tuberculosis (TB) with Tuberculin Skin Test (TST) conversions are considered to harbor latent Mycobacterium tuberculosis (Mtb), and at risk for TB. The immunologic, clinical, and public health implications of TST reversions that occur following Isoniazid preventive therapy (IPT) remain controversial. OBJECTIVES To measure frequenc...

INTRODUCTION Latent tuberculosis infection (LTBI) is detected with the tuberculin skin test (TST) before anti-TNF therapy. We aimed to investigate in vitro blood assays with TB-specific antigens (CFP-10, ESAT-6), in immune-mediated inflammatory diseases (IMID) for LTBI screening. PATIENTS AND METHODS Sixty-eight IMID patients with (n = 35) or without (n = 33) LTBI according to clinico-radiogr...

OBJECTIVE To assess the prevalence of prior tuberculin skin testing (TST) among populations at risk for HIV infection in Tijuana, Mexico, and to identify factors associated with TST. METHODS Sex workers, injection drug users, noninjecting drug users, and homeless persons > 18 years old were recruited by using targeted sampling for risk assessment interviews and serologic testing for HIV and M...

The tuberculin skin test (TST) is widely used in TB clinics to aid Mycobacterium tuberculosis (M.tb) diagnosis, but the definition and the significance of a positive test in very young children is still unclear. This study compared the TST in Gambian children at 4(1/2) months of age who either received BCG vaccination at birth (Group 1) or were BCG naïve (Group 2) in order to examine the role o...

OBJECTIVE To evaluate the prevalence of and factors associated with latent tuberculosis infection (LTBI) based on the tuberculin skin test (TST) and to estimate the boosted reaction rate among newly employed healthcare workers (HCWs). DESIGN Newly employed HCWs between January 2010 and July 2012 at Severance Hospital in South Korea were enrolled in this study. A one-step TST was conducted bef...