title: Snapshot of Quantiferon TB gold testing in Northern Mexico.
abstract: Most people infected with Mycobacterium tuberculosis have an asymptomatic condition named latent tuberculosis. These people do not have bacilli in the corporal secretions and are hard to diagnose by conventional laboratory tests. Diagnosis of latent tuberculosis infection (LTBI) in México is based on the tuberculin skin test (TST). This test has disadvantages, principally because the vaccine containing the Bacille Calmette-Guérin (BCG) is applied to 99% of this population and causes false positive TST outcomes. Recently, interferon-gamma release assays (IGRA) have been demonstrated to be a good test to detect latent tuberculosis with equal or better sensitivity to TST and without interference from BCG. However, in México the IGRA are an uncommon test due to the higher cost compared to TST. The main objective of this work was demonstrate the potential utility of the Quantiferon TB(®) gold in tube (QTB(®)-GIT) test to detect latent TB in a population from northern México. Samples from 106 subjects with close contact, or without contact, with actively infected TB patients were tested to detect LTBI. Our results show a significant difference between individuals in close contact with active TB patients (39.7%) compared to those without contact (3.2%), p < 0.01. The concordance between TST and QTB(®)-GIT was poor (κ = 0.31). Our preliminary results show that the QTB(®)-GIT has better capacity than TST to detect latent tuberculosis infection.
authors.affiliation: Northeast Biomedical Research, Mexican Social Security Institute, 2 de abril y San Luis Potosí, Colonia Independencia, 64720 Monterrey, Nuevo León, Mexico. fgonz75@hotmail.com
authors.forename: F
authors.initials: F
authors.lastname: González-Salazar
authors.forename: J
authors.initials: J
authors.lastname: Vargas-Villarreal
authors.forename: F J
authors.initials: FJ
authors.lastname: Garcialuna-Martínez
authors.forename: G
authors.initials: G
authors.lastname: Rivera
authors.forename: M G
authors.initials: MG
authors.lastname: Moreno-Treviño
authors.forename: J M
authors.initials: JM
authors.lastname: Montfort-Gardeazabal
authors.forename: E
authors.initials: E
authors.lastname: Garcialuna-Martínez
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001500:BCG Vaccine; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007223:Infant; D059425:Interferon-gamma Release Tests / Q000379:methods*; D055985:Latent Tuberculosis / Q000175:diagnosis*; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D014374:Tuberculin Test / Q000379:methods; D014376:Tuberculosis / Q000517:prevention & control / Q000635:transmission; D055815:Young Adult
chemical_list: D001500:BCG Vaccine