支气管哮喘并发肺部感染患儿下呼吸道细菌定植及相关指标研究

Lower respiratory tract bacterial colonization and related indicators of children with bronchial asthma complicated by pulmonary infection

目的探讨支气管哮喘并发肺部感染患儿下呼吸道细菌定植(LABC)与血管细胞黏附分子-1(VCAM-1)、高迁移率族蛋白-1(HMGB1)及Toll样受体2(TLR2)、Toll样受体4(TLR4)的关系。方法支气管哮喘并发肺部感染患儿240例,根据是否发生LABC分为阴性组116例和阳性组124例,另选取同期健康体检儿童50例为对照组,对比三组儿童的相关指标。结果阳性组最大呼气第一秒呼出的气量容积(FEV1)、肺活量(VC)均小于阴性组、正常对照组(P<0.05),血清VCAM-1、HMGB1及痰标本中TLR2、TLR4、肿瘤坏死因子-α(TNF-α)、白细胞介素-6(IL-6)、白细胞介素-8(IL-8)、中性粒细胞弹性蛋白酶(NE)浓度高于阴性组(P<0.05)。支气管哮喘并发肺部感染患儿血清VCAM-1、HMGB1浓度以及痰液TLR2、TLR4水平是发生LABC的独立危险因素(P<0.05);血清VCAM-1、HMGB1与痰液TLR2、TLR4联合预测支气管哮喘并发肺部感染患儿LABC的曲线下面积为0.891,敏感度、特异度分别为0.85、0.83。结论支气管哮喘并发肺部感染患儿中血清VCAM-1、HMGB1及痰液TLR2、TLR4与LABC存在密切关系,临床上可根据患儿实际情况以及结合以上指标预测患儿预后并及时采取相应的预防措施。

Objective To investigate the relationship between lower airway bacterial colonization(LABC)and related indicators such as vascular cell adhesion molecule-1(VCAM-1),high mobility group box l(HMGB1),toll-like receptor 2(TLR2)and toll-like receptor 4(TLR4)in children with bronchial asthma and pulmonary infection.Methods Two hundred and forty children with bronchial asthma and pulmonary infection treated in our hospital were selected.They were divided into a negative group(n=116)and a positive group(n=124)according to the presence or absence of LABC.At the same time,50 healthy children were selected as a normal control group.Relevant indicators were compared among the three groups.Results Forced expiratory volume in 1 second(FEV_1)and vital capacity(VC)of the positive group were smaller than those of the negative group and the normal control group(P<0.05).The levels of VCAM-1 and HMGB1 in serum,TLR2 and TLR4 in sputum,and inflammatory indicators such as tumor necrosis factor-α(TNF-α),interleukin-6(IL-6),interleukin-8(IL-8)and neutrophil elastase(NE)in the positive group were higher than those in the negative group(P<0.05).Serum VCAM-1 and HMGB1 concentrations,and the levels of TLR2 and TLR4 in sputum were independent risk factors for LABC in children with bronchial asthma and pulmonary infection(P<0.05).ROC curve analysis showed that the area under the curve of VCAM-1 and HMGB1 in serum combined with TLR2 and TLR4 in sputum for predicting LABC in children with bronchial asthma and pulmonary infection was 0.891.The sensitivity was 0.85 and the specificity was 0.83.Conclusions VCAM-1 and HMGB1 in serum,and TLR2 and TLR4 in sputum are closely related to the occurrence of LABC in children with bronchial asthma and pulmonary infection.Clinically,the prognosis can be conducted based on the child′s actual condition and the above-mentioned indicators so as to take preventive measures in time.