The Study Of Risk Factors Of Post-bronchiolitis Recurrent Wheezing In Infants

Objective:To analysis the clinical characteristics of bronchiolitis,investigate the occurrence of post-bronchiolitis recurrent wheezing and the risk factors in infants.Methods:This study was conducted on patients diagnosed with bronchiolitis admitted to the Children’s Hospital of Soochow University between November 2016 to March 2017.Multipathogen detection was performed in our study,useing direct immunofluorescence to detect common seven respiratory viruses including respiratory syncytial virus,influenza virus A and B,parainfluenza virus type 1,2,3,adenovirus and PCR of nasopharyngeal aspirates for the detection of human metapneumovirus,human Bocavirus virus,human respiratory rhinovirus,Mycoplasma pneumoniae,Chlamydia pneumoniae.At the same time,peripheral blood samples were collected to examine blood routine,humoral immunity,cellular immunity detection,Specific IgE and the serum inflammatory cytokines(IL2,TNF-α,IL4,IL5,IL13,TSLP,IL33,IL25,TIMP-1,MMP-9,MIP-1α)were detected by flow cytometry.Collect and collate the clinical data of the patients enrolled in our study.At 1,3,6,9,12,15 and 18 months after discharge,the patients were followed up by outpatient or telephone for totally 18 months.Compare the baseline data,clinical characteristics,treatment and courses,laboratory examinations,serum inflammatory cytokines chest and X-Ray between the RSV infection group and non-RSV infection group,severe group and non-severe group,post-bronchiolitis no wheezing group,one-time wheezing group and recurrent wheezing group respectively,then use the logistic regression analysis to explore the risk factors of post-bronchiolitis recurrent wheezing.Results:1.89 children with bronchiolitis were enrolled in this study,with an average age of 4.68 months.The ratio of male to female was 1.67:1.Among them,40 cases(44.9%)were younger than 3 months old,24 cases(27.1%)were 3-6 months old,19 cases(21.3%)were 6-12 months old,6 cases(6.7%)were 12-24 months old.The youngest was 1.03 months and the oldest was 19 months.2.The respiratory viruses detection rate was 52(58.4%)in 89 patients who were diagnosed with bronchiolitis.RSV infection accounted for 41(78.8%),RV for 4(7.7%),HBoV for 2(3.8%),MP for 5(9.6%).3.In our study,41(46.1%)patients were infected with RSV,with an average age of 2.7±1.5 months,and 48(53.9%)patients were non-RSV patients with an average age of 6.3±5.3 months.There were statistical significance in the proportion of age<6 months(95.1%VS58.3%),fever(0%VS 14.6%),three depressions sign(31.7%VS 4.2%)and severe disease(24.4%VS 6.3%)between the RSV infected group and non-RSV infected group(χ2=16.082,6.490,11.969,5.834;P=0.000,0.011,0.001,0.016);but there was no significant difference in birth history,eczema,specific IgE and serum inflammatory cytokines(IL-2,TNF-α,IL-4,IL-5,IL-13,TSLP,IL-33,IL-25,TIMP-1,MMP-9,MIP-1α)between the two groups(P>0.05).4.In this study,13(14.6%)children had severe bronchiolitis with an average age of 2.15±1.07 months and their ratio of male to female was 2.25:1;76(85.4%)children had non-severe bronchiolitis with an average age of 5.11±4.58 months,and their ratio of male to female was 1.62:1.The proportion of age<6 months(100%VS71.7%),breastfeeding(30.8%VS60.5%),RSV infection(76.9%VS40.8%)of the two groups were significantly different(χ2=4.999,3.993,5.834;P=0.025,0.046,0.016).5.83 patients were successfully followed up among the 89 patients.The rest 6 patients were lost because the telephone numbers were out of service or registered with wrong numbers.At 18 months after initial bronchiolitis,41 patients developed wheezing.The occurrence of one episode of wheezing was 23(27.7%),two episodes of wheezing were 5(6.0%),and 13 cases(8.4%)had more than three episodes of wheezing.6.The proportion of eczema in post-bronchiolitis recurrent wheezing group was higher than that in other groups(83.3%VS47.6%VS60.9%),which was statistically significant(χ2=6.690,P=0.035).There were no significant difference in sex,age,premature birth,birth weight,feeding patterns,family history of asthma,pet contact history,severity of disease,course of disease,sIgE,imaging manifestations and pathogenic species of infection between the two groups(P>0.05).Serum IL-2,TNF-α,IL-4,IL-5,IL-13,TSLP,IL-33,IL-25,TIMP-1,MMP-9 and MIP-1α levels were compared between the two groups,but no statistical difference was found.Logistic regression analysis showed eczema was the independent risk factor of post bronchiolitis recurrent wheezing(OR=0.222 95%CI-2.624,-0.381).Conclusions:1.Bronchiolitis caused by RSV are associated with worse disease and younger age.2.Children with severe bronchiolitis are mostly below 6-months-old,positively correlated with RSV infection and negatively correlated with breastfeeding.3.There was a certain proportion of post-bronchiolitis recurrent wheezing in children after 18 months of follow-up.4.Eczema is the independent risk factor for post-bronchiolitis wheezing in infants.5.The specific pathogens and severity of disease have no correlation with post-bronchiolitis recurrent wheezing.