TY - JOUR AU - Li, Bao-Hong AU - Guan, Wei-Jie AU - Zhu, Zheng AU - Gao, Yi AU - An, Jia-Ying AU - Yu, Xin-Xin AU - Zheng, Jin-Ping PY - 2019 TI - Methacholine bronchial provocation test for assessment of bronchial hyperresponsiveness in preschool children JF - Journal of Thoracic Disease; Vol 11, No 10 (October 30, 2019): Journal of Thoracic Disease Y2 - 2019 KW - N2 - Background: Bronchial hyperresponsiveness (BHR) has not been extensively performed in preschool children, possibly because of the difficulty in cooperating with the tests. We sought to determine the usefulness and safety of methacholine bronchial provocation test (MCh-BPT) for BHR assessment in preschool children. Methods: We recruited 252 preschool children (190 healthy and 62 with wheezing) who underwent MCh-BPT at baseline. MCh-BPT was re-scheduled in case initial attempts failed. Forced expiratory volumes in 0.5 (FEV0.5), 0.75 (FEV0.75) and one second (FEV1) were measured. We recorded the provocative dose causing 15% (PD15) or 20% reduction (PD20) in FEV0.5, FEV0.75 and FEV1, thus allowing for comparison of the diagnostic value of PD15 and PD20. Results: A total of 209 children [156 (82.1%) healthy, 53 (85.5%) with wheezing] successfully completed MCh-BPT. Compared with healthy children, a significantly greater proportion of children with wheezing had measurable PD15FEV0.5, PD15FEV0.75 and PD15FEV1 (P UR - https://jtd.amegroups.org/article/view/32454