Korean J Pediatr Infect Dis.  2008 May;15(1):51-57. 10.14776/kjpid.2008.15.1.51.

Usefulness of Interferon-γ measurement following stimulation of tuberculosis-sp ecific antig ens for diagnosis of latent tuberculosis infection in children ex posed to pulmonary tuberculosis

• Sung JY
• Kim JH
• Yang MA
• Kim SH
• Eun BW
• Lee J
• Kim NH
• Park KU
• Lee J
• Choi EH
• Lee HJ

• KMID: 2439942
• DOI: http://doi.org/10.14776/kjpid.2008.15.1.51

Abstract

PURPOSE
Whole blood interferon-γ assay was developed and many studies showed its usefulness in diagnosing tuberculosis (TB) including latent tuberculosis infection (LTBI). However, assessment in children has been limited. This study was undertaken to evaluate the usefulness of QuantiFERON-TB Gold for the diagnosis of LTBI in children exposed to pulmonary TB.
METHODS
Children who visited Seoul National University Bundang Hospital with a history of TB exposure were enrolled from January 2006 to December 2007. They were evaluated with chest x-rays, tuberculin skin test (TST) and QuantiFERON-TB Gold test. TST was retested 3 months later for those with initial negative reactivity. Definition of LTBI was made on the basis of the TST reactivity.
RESULTS
Among the 103 children with a history of TB exposure, 49 children were tested with chest x-ray, TST, and QuantiFERON-TB Gold. Twenty-two were males. Median age was 7.5 years (range; 3 months to 14.7 years). According to TST reactivity, LTBI was in 8 (19%), no infection was in 21 (50%), possible LTBI was in 13 (31%). QuantiFERON-TB Gold test was positive in 5 of the 49 subjects (10%); 3 of the 13 subjects (23.1%) in unknown status, 1 of the 8 subjects (13%) in LTBI, and 1 of the 21 subjects (5%) without infection. The agreement between the QuantiFERON-TB Gold and the TST was poor (κ=0.101).
CONCLUSION
QuantiFERON-TB Gold showed poor sensitivity for the diagnosis of LTBI in children with exposure to TB. QuantiFERON-TB Gold alone does not seem to be useful in the diagnosis of LTBI in children.

Keyword

Latent tuberculosis infection; Tuberculin skin test; Interferon gamma assay; Children

MeSH Terms

Child*
Diagnosis*
Humans
Latent Tuberculosis*
Male
Seoul
Skin Tests
Thorax
Tuberculin
Tuberculosis
Tuberculosis, Pulmonary*
Tuberculin