PT - JOURNAL ARTICLE AU - Soler-Garcia, Aleix AU - Gamell, Anna AU - Pérez-Porcuna, Tomàs AU - Soriano-Arandes, Antonio AU - Santiago, Begoña AU - Tórtola, Teresa AU - Ruiz-Serrano, María Jesús AU - Korta Murua, José Javier AU - Bustillo-Alonso, Matilde AU - Garrote-Llanos, María Isabel AU - Rodríguez-Molino, Paula AU - Piqueras, Ana Isabel AU - Tagarro, Alfredo AU - Monsonís, Manuel AU - Tebruegge, Marc AU - Noguera-Julian, Antoni ED - TI - Performance of QuantiFERON-<em>TB</em> Gold Plus assays in children and adolescents at risk of tuberculosis: a cross-sectional multicentre study AID - 10.1136/thoraxjnl-2021-217592 DP - 2022 Dec 01 TA - Thorax PG - 1193--1201 VI - 77 IP - 12 4099 - http://thorax.bmj.com/content/77/12/1193.short 4100 - http://thorax.bmj.com/content/77/12/1193.full SO - Thorax2022 Dec 01; 77 AB - Introduction The QuantiFERON-TB Gold Plus (QFT-Plus) assay, which features two antigen-stimulated tubes (TB1 and TB2) instead of a single tube used in previous-generation interferon-gamma release assays (IGRAs), was launched in 2016. Despite this, data regarding the assay’s performance in the paediatric setting remain scarce. This study aimed to determine the performance of QFT-Plus in a large cohort of children and adolescents at risk of tuberculosis (TB) in a low-burden setting.Methods Cross-sectional, multicentre study at healthcare institutions participating in the Spanish Paediatric TB Research Network, including patients &lt;18 years who had a QFT-Plus performed between September 2016 and June 2020.Results Of 1726 patients (52.8% male, median age: 8.4 years), 260 (15.1%) underwent testing during contact tracing, 288 (16.7%) on clinical/radiological suspicion of tuberculosis disease (TBD), 649 (37.6%) during new-entrant migrant screening and 529 (30.6%) prior to initiation of immunosuppressive treatment. Overall, the sensitivity of QFT-Plus for TBD (n=189) and for latent tuberculosis infection (LTBI, n=195) was 83.6% and 68.2%, respectively. The agreement between QFT-Plus TB1 and TB2 antigen tubes was excellent (98.9%, κ=0.961). Only five (2.5%) patients with TBD had discordance between TB1 and TB2 results (TB1+/TB2−, n=2; TB1−/TB2+, n=3). Indeterminate assay results (n=54, 3.1%) were associated with young age, lymphopenia and elevated C reactive protein concentrations.Conclusions Our non-comparative study indicates that QFT-Plus does not have greater sensitivity than previous-generation IGRAs in children in both TBD and LTBI. In TBD, the addition of the second antigen tube, TB2, does not enhance the assay’s performance substantially.Data are available upon reasonable request. Data are available upon reasonable request to the corresponding author.