Source: Annual Congress 2008 - Diagnosis of tuberculosis: problems and perspectives
Disease area: Respiratory infections

Abstract

The present distribution of tuberculin skin test (TST) reactions is not well known in areas of low prevalence of TB. Therefore, TST reactivity was analyzed in relation to previous Bacille Calmette-Guérin (BCG) vaccination and other variables in 1190 healthy young adults in Sweden. A subgroup of 287 non-vaccinated subjects born in Sweden was skin-tested with Mycobacterium avium sensitin. A linear regression model was created for the relative contribution of background factors to TST reactivity.
In BCG-vaccinated and non-vaccinated subjects, respectively, 34% vs. 91% of the subjects were non-reactive (i.e. indurations of 0 mm), and the mean TST was 7.5 mm vs.0.7 mm. In BCG-vaccinated subjects, TST reactions of ≥6 mm, ≥10 mm and ≥15 mm were found in 62%, 42% and 9.5% of the subjects, respectively. Corresponding figures of non-vaccinated subjects were 4.7%, 2.9% and 0.5%. The expected contribution to TST reactivity was 6.0 mm for a history of BCG vaccination (99% CI 5.2–6.9), 3.0 mm for a country of birth with medium/high incidence of TB (99% CI 1.4-4.5), 1.4 mm per 10 years of age (99% CI 0.4-2.3) and 0.3 mm for male gender (n.s.). In sensitin-tested subjects, 2.1% had a TST reaction larger than the sensitin reaction.
In conclusion, a large proportion of BCG-vaccinated subjects showed considerable TST reactivity, while most non-vaccinated subjects were non-reactive. Geographic origin and age, but not gender, had decisive influence on TST reactivity in addition to BCG vaccination. Most TST reactions in non-vaccinated Swedish subjects were probably caused by cross-reactivity with environmental mycobacteria. The cut-off value for a positive TST in low-prevalence settings will be discussed.

Rating:

Share or cite this content

Citations should be made in the following way:
H. Fjällbrant, A. Rutqvist, O. Widström, G. Zetterström, M. Ridell, L. O. Larsson (Goteborg, Stockholm, Sweden). Tuberculin skin test reactivity of young adults in a country with low prevalence of tuberculosis. Eur Respir J 2008; 32: Suppl. 52, 2386

Member's Comments

No comment yet.

Related content which might interest you: Evaluation of Tuberculin skin test size and risk of tuberculosis in children household contact Source: International Congress 2018 – Groups who are susceptible to tuberculosis: children, pregnant women and elderly people Year: 2018 Tuberculosis at children and adolescents: tuberculin skin test in close contact investigation Source: Eur Respir J 2002; 20: Suppl. 38, 549s Year: 2002 The prevalence of tuberculin skin test positivity and effect of number of BCG vaccination on tuberculin induration size in Kahramanmaras city, Turkey Source: Annual Congress 2009 - Bacterial infections of upper and lower respiratory tract in childhood Year: 2009 The role of tuberculin skin test in the diagnosis of latent TB infection among military men in South Korea Source: Eur Respir J 2006; 28: Suppl. 50, 168s Year: 2006 The prevalence of latent tuberculosis infection in a children social center: Comparison of QuantiFERON-TB Gold with tuberculin skin testing Source: Annual Congress 2010 - Tuberculosis in children Year: 2010 The tuberculin skin test and QuantiFERON test comparison in the diagnosis of latent tuberculosis infection in children Source: Annual Congress 2010 - Tuberculosis in children Year: 2010 Tuberculin skin test and IGRA test in the diagnosis and follow-up of bacteriologically confirmed pulmonary tuberculosis in HIV negative adults Source: Annual Congress 2012 - Tuberculosis and immunologic assays Year: 2012 Comparison of the QuantiFERON-TB and tuberculin skin test for detection of latent tuberculosis infection in cancer patients in a developing country Source: ERJ Open Res, 5 (4) 00258-2018; 10.1183/23120541.00258-2018 Year: 2019 Diagnosing TB infection in children: analysis of discordances using in vitro tests and the tuberculin skin test Source: Eur Respir J 2011; 37: 1166-1174 Year: 2011 Utility of tuberculin and anergy skin testing in predicting TB infection in HIV infected children in Constantza county Source: Eur Respir J 2003; 22: Suppl. 45, 157s Year: 2003 Prevalence of tuberculosis (TB) skin test positivity among prisoners in Crete Source: Eur Respir J 2002; 20: Suppl. 38, 165s Year: 2002 Tuberculin skin test screening for tuberculosis in Nazilli district prison Source: Eur Respir J 2002; 20: Suppl. 38, 23s Year: 2002 Performance of the tuberculin skin test and Interferon-gamma release assays for detection of tuberculosis infection in immunocompromised patients in a TB endemic population Source: Annual Congress 2010 - Immune responses for the diagnosis of tuberculosis Year: 2010 Tuberculin skin test sensivity in asthma patients Source: Annual Congress 2011 - Diagnosis and treatment of inflammatory respiratory diseases Year: 2011 Screening for TB infection in children using skin tests with tuberculin and recombinant allergen (CFP-10-ESAT-6) Source: Virtual Congress 2020 – Non-tuberculous mycobacteria and latent tuberculosis infection Year: 2020 Quantiferon and tuberculin skin test for detection of tuberculosis infection in immunocompromised patients Source: Annual Congress 2010 - Clinical tuberculosis Year: 2010 The comparison of tuberculin skin test and quantiferon TB gold test in latent tuberculosis infection in health workers Source: Annual Congress 2008 - New tests and methods to diagnose tuberculosis infection and disease and to monitor treatment Year: 2008 Tuberculin test in BCG vaccinated children Source: Annual Congress 2008 - Infectious lung diseases including tuberculosis Year: 2008 Variations in the definition of a positive tuberculin skin test across Europe Source: Annual Congress 2008 - Clinical epidemiology of tuberculosis Year: 2008 Tuberculin skin test size and risk of tuberculosis: A 12-year follow-up of contacts of TB cases Source: Annual Congress 2011 - Tuberculin skin tests, interferon-gamma release assays and beyond Year: 2011