Performance of an interferon-gamma release assay for diagnosing latent tuberculosis infection in children.
Newly developed interferon-gamma release assays have become commercially available to detect tuberculosis (TB) infection in adults. However, little is known about their performance in children. We compared test results between the QuantiFERON-TB Gold test (QFT) and tuberculin skin test (TST) in young children living with pulmonary TB patients in Cambodia. Of 195 children tested with both QFT and TST, the TST-positive rate of 24% was significantly higher than the QFT-positive rate of 17%. The agreement between the test results was considerable (kappa-coefficient 0.63). Positive rates increased from 6% to 32% for QFT and from 15% to 43% for TST, according to the sputum smear grades of the index cases. The presence of Bacille Calmette-Guérin (BCG) scars did not significantly affect the results of TST or QFT in a logistic regression analysis. In conclusion, QFT can be a substitute for TST in detecting latent TB infection in childhood contacts aged <or= 5 years, especially in those who may have a false-positive TST due to BCG vaccination or non-tuberculous mycobacterial infection.
Okada
K
K
Japan International Cooperation Agency/National Tuberculosis Control Project, Phnom Penh, Cambodia. okadak@jata.or.jp
Mao
T E
TE
Mori
T
T
Miura
T
T
Sugiyama
T
T
Yoshiyama
T
T
Mitarai
S
S
Onozaki
I
I
Harada
N
N
Saint
S
S
Kong
K S
KS
Chhour
Y M
YM
D002160:Cambodia; D016009:Chi-Square Distribution; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007371:Interferon-gamma / Q000097:blood*; D008297:Male; D012680:Sensitivity and Specificity; D014374:Tuberculin Test; D014397:Tuberculosis, Pulmonary / Q000175:diagnosis*
D007371:Interferon-gamma