Abstract:

Objective　To explore the advantages and disadvantages of two methods for detecting respiratory pathogens in children with lower respiratory tract infection, and the correlation between C-reactive protein (CRP), procalcitonin (PCT), and interleukin (IL)-6. Methods　Using cohort study, a total of 239 children with lower respiratory tract infection treated at The Second Affiliated Hospital of Guangzhou Medical University from September 2020 to November 2020 were divided into a respiratory tract antigen group (121 cases) and a serum antibody group (118 cases). The respiratory tract antigen group used immunofluorescence assay to detect respiratory antigen from throat swabs. In the serum antibody group, the indirect immunofluorescence method was used to detect the related pathogen IgM in the serum of the children. The blood routine, CRP, PCT, and IL-6 were detected in both groups. χ², t, and rank sum tests and Pearson correlation analysis were applied. Results　There were no statistical differences in general information (age, gender, course of disease, and clinical symptoms) and inflammatory indicators (white blood cell count, neutrophil percentage, CRP, and PCT) between the respiratory tract antigen group and the serum antibody group (all P>0.05). The level of IL-6 was 6.44 (2.29, 13.24) ng/L in the respiratory tract antigen group, and was 6.78 (3.05, 14.72) ng/L in the serum antibody group, with a statistical difference (P<0.05). The positive rate of pathogen detection was 30.58% (37/121) in the respiratory tract antigen group, and was 11.02% (13/118) in the serum antibody group, with a statistical difference (P<0.05). IL-6 was correlated with CRP (R²=0.254), and the equation was Y=-0.001X²+0.929X+5.677 (0<X<200). Conclusion　In children with lower respiratory tract infection, the respiratory antigen detection is superior to antibody detection and IL-6 can cause 25.4% CRP change in children.

Key words:

Lower respiratory tract infection, Respiratory tract pathogens, Antigen detection, Antibody detection, Inflammatory indicators

摘要：

目的　探讨两种呼吸道病原检测方法在儿童下呼吸道感染中的优劣，以及C反应蛋白（CRP）、降钙素原（PCT）、白细胞介素（IL）-6之间的相关性。方法　采用队列研究，选取2020年9月至2020年11月广州医科大学附属第二医院收治的239例下呼吸道感染患儿为研究对象，分为呼吸道抗原组（抗原组）121例、血清抗体组（抗体组）118例。抗原组采用免疫荧光法检测患儿咽拭子呼吸道抗原，抗体组采用间接免疫荧光法检测患儿血清中相关病原体IgM。同时两组均检测血常规、CRP、PCT、IL-6。采用χ²检验、t检验、秩和检验和Pearson相关性分析。结果　抗原组、抗体组的一般资料（年龄、性别、病程、临床症状）及炎症指标（白细胞计数、中性粒细胞百分比、CRP、PCT）比较，差异均无统计学意义（均P>0.05）；抗原组IL-6为6.44（2.29，13.24）ng/L，抗体组为6.78（3.05，14.72）ng/L，两组比较，差异有统计学意义（P<0.05）。在病原检测的阳性率上，抗原组为30.58%（37/121），抗体组为11.02%（13/118），两组比较，差异有统计学意义（P<0.05）。在炎症指标相关性中，IL-6与CRP存在相关性，R²为0.254，方程为Y=-0.001X²+0.929X+5.677（0<X<200）。结论　在儿童下呼吸道感染中，呼吸道抗原检测优于抗体检测，同时IL-6可引起25.4%的CRP变化。

关键词:

下呼吸道感染, 呼吸道病原, 抗原检测, 抗体检测, 炎症指标