2020-2022年儿童下呼吸道细菌感染病原体变迁及血清WBC、PCT、CRP水平分析

Analysis of changes in bacterial pathogens and serum WBC,PCT,and CRP levels in children with lower respiratory tract infections from 2020 to 2022

目的分析本地区儿童下呼吸道细菌感染患儿的病原体分布情况及血清白细胞计数、降钙素原、C-反应蛋白水平。方法选取2020-2022年,于本院儿科接诊的1853例下呼吸道感染患儿,其中下呼吸道分泌物细菌病原学阳性患儿278例。收集痰标本分别接种于不同培养基中。培养后经分离纯化后,采用VITEK 2 Compact全自动分析系统进行鉴定。对主要病原菌经培养后,采用纸片扩散法进行药敏试验。抽患儿静脉血并测定血清降钙素原(PCT)水平和C反应蛋白(CRP)水平,并利用细胞自动计数仪检测患儿血清白细胞(WBC)水平。结果2020-2022年下呼吸道感染患儿分别为628、549和676例。其中细菌感染例数分别为94、72和112例,阳性率分别为14.97%、13.11%和16.57%。下呼吸道细菌感染患儿共检出病原菌278株,其中革兰阴性菌167株,革兰阳性菌111株。革兰阴性菌以流感嗜血杆菌、肺炎克雷伯菌为主,革兰阳性菌以肺炎链球菌、金黄色葡萄球菌为主。2020-2022年,流感嗜血杆菌、产气肠杆菌的占比逐年升高,卡他莫拉菌、大肠埃希菌、阴沟肠杆菌、鲍曼不动杆菌、肺炎链球菌的占比逐年降低。45株流感嗜血杆菌对氨苄西林、头孢呋辛、复方新诺明的耐药率高于40%,39株肺炎克雷伯菌对氨苄西林、四环素、复方新诺明的耐药率高于40%,均未产生对亚胺培南、美罗培南、阿米卡星的耐药株。65株肺炎链球菌对青霉素、苯唑西林、红霉素、四环素、复方新诺明的耐药率高于40%,36株金黄色葡萄球菌对青霉素、苯唑西林、红霉素的耐药率高于40%,均未产生对万古霉素、替考拉宁的耐药株。278例下呼吸道细菌感染患儿为细菌组,选择同期100例下呼吸道非细菌感染患儿为非细菌组。细菌组患儿血清WBC、PCT、CRP阳性率高于非细菌组患儿,差异有统计学意义(P<0.05)。结论下呼吸道细菌感染主要以流感嗜血杆菌、肺炎克雷伯菌、肺炎链球菌、金黄色葡萄球菌为主;细菌组患儿血清WBC、PCT、CRP阳性率高于非细菌组患儿。

Objective To analyze the pathogen distribution,serum WBC count,Procalcitonin and C-reactive protein levels of children with lower respiratory tract bacterial infection in this area.Methods A total of 1853 children with lower respiratory tract infections admitted to our pediatric department from 2020 to 2022 were selected,including 278 children with positive bacterial pathogens in lower respiratory tract secretions.The sputum samples were collected and inoculated into different culture media.After cultivation,isolation and purification,identification was carried out by the VITEK 2 Compact fully automated analysis system.After culturing the main pathogenic bacteria,the drug sensitivity testing were carried out by paper diffusion method.The venous blood of the children was drawn and the serum levels of procalcitonin(PCT)and C-reactive protein(CRP)were measured,and the serum white blood cell(WBC)level of the child were detected by an automatic cell counter.Results From 2020 to 2022,there were 628,549,and 676 children with lower respiratory tract infections.The number of bacterial infections was 94,72,and 112,with positive rates of 14.97%,13.11%,and 16.57%,respectively.A total of 278 strains of pathogenic bacteria were detected in children with lower respiratory tract bacterial infections,including 167 strains of Gram negative bacteria and 111 strains of Gram positive bacteria.Gram negative bacteria were mainly Haemophilus influenzae and Klebsiella pneumoniae,while Gram positive bacteria were mainly Streptococcus pneumoniae and Staphylococcus aureus.From 2020 to 2022,the proportion of H.influenzae and Enterobacteriaceae aerogenes had increased year by year,while the proportion of Moraxella catarrhalis,Escherichia coli,E.cloacae,Acinetobacter baumannii and S.pneumoniae had decreased year by year.45 strains of H.influenzae were more than 40%resistant to ampicillin,cefuroxime and compound sulfamethoxazole,39 strains of K.pneumoniae were more than 40%resistant to ampicillin,tetracycline and compound sulfamethoxazole,and none of them was resistant to imipenem,meropenem and amikacin.65 strains of S.pneumoniae were more than 40%resistant to penicillin,oxacillin,erythromycin,tetracycline and compound sulfamethoxazole,and 36 strains of S.aureus were more than 40%resistant to penicillin,oxacillin and erythromycin.None of them was resistant to vancomycin and teicoplanin.278 children with lower respiratory tract bacterial infections were selected as the bacterial group,while 100 children with lower respiratory tract non bacterial infections during the same period were selected as the non bacterial group.The positive rates of serum WBC,PCT,and CRP in the bacterial group were higher than those in the non bacterial group,and the difference was statistically significant(P>0.05).Conclusion The main bacterial infections in the lower respiratory tract were H.influenzae,K.pneumoniae,Streptococcus pneumoniae,and S.aureus.The positive rates of WBC,PCT,and CRP in the serum of children in the bacterial group were higher than those in the non bacterial group.