The Clinical Value Of Pentraxin3 In Community-Acquired Pneumonia Of Children

Background:Community-acquired pneumonia is a child without obvious immunosuppression contracts pneumonia before the hospital stay or within 48 h,which used to appear in children,especially in infants.Community-acquired pneumonia is the most common cause of hospitalization in children and the leading cause of death in children under the age of 5.It mainly shows fever,cough,wheezing,breathing difficulty and severe extra-pulmonary complications of other systems(such as heart failure,toxic encephalopathy,sepsis and so on).Although much new powerful antibiotics continuing to be yielded,it's morbidity and mortality are not reduced significantly.The early diagnosis and identification of the severity to the disease is of paramount importance.So far,there is no objective index to assess the sensitivity and specificity of the severity of pneumonia in children.PTX3 is an inflammatory factor that can be produced by leukocytes and pulmonary epithelial cells.In recent years,many national and international studies in pneumonia suggest that PTX3 is related to the early identification and severity of pneumonia.Objective:To investigate the clinical value of pentraxins 3(PTX3)in children's community-acquired pneumonia.Methods:We collected 122 inpatients diagnosed with community-acquired pneumonia in Department of Respiratory Medicine and Intensive Care Unit(ICU)of Hunan Children's Hospital from 2016.03 to 2017.01,whose age>28 days,<18 years,including 82 males and 40 females.We collected 20 healthy subjects as control group,including 12 males and 8 females.According to the severty of illness,all children were divided into mild group,severe group and control group.According to respiratory failure or not,all children were divided into the respiratory failure group and the non-respiratory failure group.According to the optimal thresholds of PTX3 in the study on respiratory failure,all children were divided into two groups: group A(?165.30ng/ml)and group B(>165.30ng/ml).According to the pathogens,all children were divided into four groups: bacterial group,virus group,hybrid group and other group.To analyze the variation of serum PTX3 expression in children with community-acquired pneumonia,affected by different pathogens and different severity.Results:1.The PTX3 level within 24 h after admission of patients in severe group was significantly higher than that of patients in mild group(P<0.05).The PTX3 level of patients in mild group and severe group was higher than control group and the difference was statistically significant(P<0.05);PTX3 level of patients with respiratory failure was higher than non-respiratory failure group and the difference was statistically significant(P<0.05).2.Receiver Operating Characteristic analysis with TNF-?,CRP,PCT and PTX3 showed that the area under the curve of PTX3 was largest(0.783,P < 0.001)in diagnosis of respiratory failure.The sensitivity and specificity were 0.826 and 0.657 respectively,when PTX3 equaled to 165.30ng/ml.The sensitivity and specificity were 0.783 and 0.566,respectively when PCT equaled to 0.25ng/ml.The sensitivity and specificity were 0.783 and 0.586,respectively when TNF-? equaled to 14.59ng/ml.The sensitivity and specificity were 0.783 and 0.515,respectively when CRP equaled to 9.06mg/L.3.The correlation analysis between PTX3 and other inflammatory biomarkers and clinicopathological features of patients with community-acquired pneumonia showed that TNF-?,PCT was positively correlated with PTX3 level,the correlation coefficients were 0.59,0.18 respectively,PTX3 level was positively correlated with respiratory frequency(r = 0.388),and negatively correlated with pulse oximetry(r =-0.251)and Pa O2(r =-0.316).The DD level of PTX3 severe group(group B)was higher than that of the mild group(P = 0.022).There was a positive correlation between the PTX3 level and the DD line(r = 0.228,P = 0.012).4.Dynamic observation of PTX3 level in children with CAP: PTX3 level[M(IQR)](ng/ml)was highest at 24 h after hospital admission,equaling to 152.55(152.22);PTX3 equaled to 89.12(111.44)after 3 days' treatment;and decreased to 47.26(68.51)after 7 days' treatment,and the difference among these time points were statistically significant(H=74.33,P<0.01).The difference of PTX3 level between mild group and severe group in distinct time points was also statistically significant.In mild group,PTX3 level was decreased to low level in 7 days,while PTX3 level in severe group remained relatively high.5.According to etiology in patients,the PTX3 levels were 162.80(166.72),117.65(126.55),164.99(168.40)and 131.66(162.12),respectively represented by the groups of bacterial,virus,mixed,and others,and all the inter-group differences were statistically significant(P=0.044).Multiple comparisons showed that the inter-group differences between mixed group and virus,mixed group and other group were statistically significant(P<0.05),while differences between virus group and bacterial group,bacterial group and mixed group,virus group and other,bacterial group and other group exhibited none statistically significant(P<0.05).However,there was no significant difference in CRP,PCT and TNF-? between the four groups.Conclusion:1.The level of serum PTX3 in children with community-acquired pneumonia was positively correlated with TNF-?,PCT and D-dimer.2.Serum PTX3 can be used as a new biomarker to reflect the severity of community-acquired pneumonia of children.