title: Influencial factors of the performance of interferon-γ release assays in the diagnosis of childhood tuberculosis.
abstract: Diagnosis of active tuberculosis (TB) in children remains difficult. This study aimed at evaluating the ability of interferon-gamma release assays (IGRAs) in the detection of active TB in human immunodeficiency virus-negative children vaccinated with Bacille Calmette-Guérin and investigating the effect of prednisolone treatment on the IGRAs performance. Among the 162 children with suspected TB disease recruited in China, 60 were tested with QuantiFERON-TB Gold In Tube (QFT-GIT) and 102 were tested with T-SPOT.TB. QFT-GIT presented a sensitivity of 83.9 % (95 % CI 66.9-93.4 %) and a specificity of 88.5 % (95 % CI 70.2-96.8 %), while T-SPOT.TB had a sensitivity of 75.9 % (95 % CI 63.4-85.2 %) and a specificity of 94.7 % (95 % CI 81.8-99.5 %). The positive predictive value was high in both assays, 92.9 % for QFT-GIT and 95.7 % for T-SPOT.TB. In total of these two kinds of IGRAs, false negative rate was significantly higher in children receiving systemic prednisolone (1 mg/kg/day) therapy for >1 week (two tested with T-SPOT.TB and five tested with QFT-GIT) than in those with ≤1 week of prednisolone therapy and without prednisolone therapy (57.1 vs. 18.3 %, p = 0.035). There was no significant difference of the positive rate of both tests in children <5 years old compared with those ≥5 years old. Both types of IGRAs showed good diagnostic values in detecting childhood TB before microbiological evidence was available. Glucocorticoids had a significant negative influence on IGRAs if treated for >1 week. Age made no difference on the performance of these tests in children.
authors.affiliation: Shanghai Public Health Clinical Center, Fudan University, Shanghai, China.
authors.forename: Tao
authors.initials: T
authors.lastname: Li
authors.forename: Lei
authors.initials: L
authors.lastname: Bao
authors.forename: Ni
authors.initials: N
authors.lastname: Diao
authors.forename: Feng
authors.initials: F
authors.lastname: Sun
authors.forename: Yan
authors.initials: Y
authors.lastname: Gao
authors.forename: Ka-Wing
authors.initials: KW
authors.lastname: Wong
authors.forename: Xiuhong
authors.initials: X
authors.lastname: Xi
authors.forename: Xuhui
authors.initials: X
authors.lastname: Liu
authors.forename: Sen
authors.initials: S
authors.lastname: Wang
authors.forename: Jing
authors.initials: J
authors.lastname: Wu
authors.forename: Ma
authors.initials: M
authors.lastname: Hui
authors.forename: Xiaoyong
authors.initials: X
authors.lastname: Fan
authors.forename: Ying
authors.initials: Y
authors.lastname: Zhang
authors.forename: Wenhong
authors.initials: W
authors.lastname: Zhang
authors.forename: Shuihua
authors.initials: S
authors.lastname: Lu
mesh_terms: D000293:Adolescent; D000893:Anti-Inflammatory Agents / Q000627:therapeutic use*; D002648:Child; D002675:Child, Preschool; D002681:China; D005188:False Negative Reactions; D005260:Female; D006678:HIV; D006801:Humans; D007223:Infant; D059425:Interferon-gamma Release Tests / Q000379:methods*; D008297:Male; D011237:Predictive Value of Tests; D011239:Prednisolone / Q000627:therapeutic use*; D012680:Sensitivity and Specificity; D014376:Tuberculosis / Q000175:diagnosis*
chemical_list: D000893:Anti-Inflammatory Agents; D011239:Prednisolone