The Etiology And Analysis Of Chronic Cough In 457 Children In The Hengyang Area

Objective: To explore the etiological composition ratio and analyze the etiological characteristics of 457 children with a chronic cough in a single center in the Hengyang area.To investigate the clinical application value of chest imaging,pulmonary ventilation function,and exhaled nitric oxide in the diagnosis of chronic cough.Methods: In this study,a single-center retrospective clinical research survey method was used to collect and analyze the data of 457 children who visited the Pediatric Outpatient Clinic of the Second Affiliated Hospital of the University of South China in Hengyang City from January2019 to January 2022.Results: 1.Among the 457 children,338(74.0%)had single etiology,117(25.6%)had dual etiology,and 2(0.4%)had triple etiology.The top three single etiologies were upper airway cough syndrome in 145 cases(31.7%),cough variant asthma in 119 cases(26.0%),and post-infection cough in 41 cases(9.1%).The most common dual etiology was upper airway cough syndrome combined with cough variant asthma in 95 cases(20.8%).There were statistically significant differences in the etiology of different cough properties(dry cough,wet cough),different age groups(<3 years old,3-6 years old,> 6 years old)and different disease course groups(< 3 months,3-6 months old,> 6 months old)(P < 0.05).There was no significant difference in the etiology composition of different genders(male,female)and different residential areas(central urban areas,countylevel urban areas,farming areas,and others)(P>0.05).2.For children with wet cough,the specificity of imaging examination was 89.2%,and the positive predictive value was 69.8%.Among the top three single etiologies,the sensitivity of lung function tests for these three diseases is not high,and the specificity for cough variant asthma is high.In children with cough variant asthma,the sensitivity and specificity of exhaled nitric oxide detection were better than those of the other two groups.Receiver curve analysis was performed on the application of exhaled nitric oxide in cough variant asthma.When the cut-off value was17.5ppb,the sensitivity was 96.1%,the specificity was 80.2%,the area under the curve was 0.989,and 95% was acceptable.The confidence interval is(0.983,0.996).Conclusions: 1.The top three causes of chronic cough among 457 children in a single center in the Hengyang area are upper airway cough syndrome,cough variant asthma,and post-infection cough.Among the multiple etiologies,upper airway cough syndrome combined with cough variant asthma is the most common.There were differences in the proportion of etiology among different cough types,age groups,and disease duration groups.2.Improving the examination of chest imaging,pulmonary ventilation function,and exhaled nitric oxide is of great value in identifying the cause of cough in children with chronic cough.