Bacterial Pathogens And Their Drug Resistance In Children With Lower Respiratory Tract Infection Between 2019 And 2020: A Single-center Report

Objective:To analyze the pathogenic spectrum,use of antibiotics,drug resistance,and the influence of COVID-19 prevention and control measures on the pathogenic bacteria spectrum in hospitalized children with lower respiratory tract infection in a tertiary hospital between 2019 and 2020,in order to provide reference for rational use of antibiotics.Methods:The bacterial culture results of sputum and alveolar lavage fluid of 14,533 patients hospitalized for lower respiratory tract infection in Pediatric Department of So-and-so hospital from January 2019 to December 2020 were collected.IBM SPSS Statistics 26 software was used to conduct Chi-square test for counting data.The pathogenic bacteria spectrum during the two years was analyzed.and the effects of gender,age,length of hospital stay.season,severity of illness,and current COVID-19 control measures on the pathogenic bacteria spectrum,drug resistance and use of antibiotics were also analyzed.Results:1.Detection of pathogenic bacteria: From January 2019 to December 2020,a total of 14,533 qualified lower respiratory tract specimens collected form pediatric department of So-and-so hospital were sent for culture and 2563 pathogenic strains were isolated,with a positive rate of 17.63%.Of the isolated strains,Gram-negative bacterium accounted for 54% and gram-positive bacterium accounted for 46%.The top five common pathogens were Streptococcus pneumoniae(SP)(33.1%or 33.15%),Haemophilus influenzae(HI)(31.8% or 23.29%),Staphylococcus aureus(SA)(11.36% or 15.42%),Moraxella catarract(9.5% or 12.8%)and Escherichia coli(4.09%/3.25%).The top five pathogens in general wards was the same as the overall situation,while in Pediatric Intensive Care Unit,the proportion of HI and SA was higher than that of SP.2.The influence of gender,age,season,severity of illness and length of hospital stay on the distribution of pathogenic bacteria:the positive rate of pathogenic bacteria in boys was higher than that in girls,and the top five pathogenic bacteria were SP,HI,SA,MC and E.Coli,and there was no statistical difference between the two groups.The younger the age,the higher the positive detection rate of pathogens.Except for the infant group in 2019 and the school age group in 2020,in which Hi was the most frequently detected pathogen,SP was the dominant pathogen in all other age groups.The positive rate of pathogens peaked in autumn and decreased to the lowest in winter.Moreover,there were differences in the distribution of pathogens in different seasons.The proportion of HI was higher than that of SP in spring and winter,while SP was dominant in other seasons.The positive rate of pathogens was the highest in patients who were hospitalized for more than 22 days.There was no statistical difference in positive rate between mild and severe cases,however,in severe cases,HI was more often detected than SP.3.Drug resistance of common pathogens:(1)Gram-positive bacteria:SP had low resistance rate to penicillin,the highest was 3.5% in two years,and high resistance rate to macrolides and clindamycin(> 90%).SA was generally resistant to penicillin(>90%)and MRSA accounted for 37.9%.(2)Gram-negative bacteria:The drug resistance rate of HI to β-lactam and sulfonamides was more than 70%,and it was generally sensitive to cephalosporins(except cefuroxime resistance 41.9%,no other cephalosporin-resistant strains were found).MC had high sensitivity to other antibacterial drugs except the drug resistance rate of β-lactam was 23.5%.E.coli,Klebsiella pneumoniae(KP)and Acinetobacter Baumannii(AB)were generally resistant to β-lactams,cephalosporins,sulfonamides,quinolones and macrolides.Among them,the detection rate of carbapenem-resistant Enterobacter(CRE)was 6.7% and the detection rate of carbapenem-resistant Klebsiella pneumoniae was 6.7%.CRKP was about 8.5% and carbapenem-resistant Acinetobacter Baumannii(CRAB)increased from 32% in 2019 to 50% in 2020.Pseudomonas aeruginosa(PA)was generally sensitive to common antibiotics,and the detection rate of drug resistant strains was low,the highest was 9.1%.4.Use of commonly used antibacterial drugs:The commonly used antibiotics for children’s lower respiratory tract infections in Guizhou People’s Hospital were cefotaxime,cefoperazone sulbactam,amoxicillin clavulanate,piperacillin tazobactam,azithromycin and ceftriaxone.In 2019,the proportion of non-restricted class antibiotics was 57.66%,the proportion of restricted class antibiotics was38.26%,and the proportion of special use class antibiotics was 4.08%.In 2020,the use of non-restricted-class antibiotics accounted for 63.49%,restricted-class antibiotics accounted for 28.89%,and special-use antibiotics accounted for 6.62%.Commonly used antibiotics for PICU were piperacillin/tazobactam,cefotaxime,azithromycin cefoperazone/sulbactam and meropenem.In 2019,the proportion of unrestricted use antibiotics was 33.28%,restricted use 47.77% and special use 16.96%.In2020,unrestricted use antibiotics accounted for 30.96%,restricted use drugs for56.64%,and special use drugs for 12.4%.The commonly used antibiotics in severe cases were cefotaxime,cefoperazone sulbactam,azithromycin,piperacillin tazobactam and amoxicillin clavulanate.In 2019,the use of antibiotics for unrestricted use accounted for 43.39%,restricted use accounted for 55.29%,and special use accounted for 1.32%.In 2020,the use of antibiotics for unrestricted use accounted for41.62%,restricted use accounted for 58.2% and special use accounted for 0.18%.5.Impact of COVID-19 prevention and control measures on the distribution of pathogenic bacteria.The total volume of outpatient and emergency services in The Pediatric Department of So-and-so hospital in 2020 decreased by 54% compared with 2019,and the number of inpatients in inpatient wards from January to March2020 also decreased by 28.7% compared with the same period in 2019.In 2019,7840 lower respiratory tract specimens were collected,and 1610 pathogenic strains were isolated,with a positive detection rate of 20.54%.In 2020,6693 samples were submitted for examination,and 953 strains of pathogens were isolated,with a positive detection rate of 14.24%.Statistical difference in positive detection rate was found between the two years,indicating that measures on COVID-19 prevention and control help to block the spread of pathogenic bacteria and reduce the incidence of lower respiratory tract infection of related pathogens.Conclusions:1.The common pathogens of lower respiratory tract infection in children in So-and-so hospital were SP,HI,SA,MC and E.Coli,and SP ranked first.It is fully consistent with the national bacterial resistance test data of children and the Code for the Diagnosis and Treatment of Community-acquired Pneumonia in Children(2019Edition).2.There were differences inpathogenic bacteria spectrum in children with different gender,age,season,disease status and length of hospitalization.The positive rate of pathogen strains in boys was higher than that in girls.Younger age and longer hospital stay were consistant with higher detection rate of pathogenic bacteria and higher proportion of HI in infants and school-age children.The detection rate of pathogenic bacteria was the highest in autumn and the lowest in winter,and HI was the dominant pathogenic bacteria in winter and spring,SP was the dominant pathogenic bacteria in summer and autumn.HI was the main pathogenic bacteria in severe cases,SP was the main pathogenic bacteria in mild cases.Medical institutions at all levels should strengthen monitoring of children’s respiratory diseases and improve access to medical treatment.3.The proportion of unrestricted-use,restricted-use and special-use antibiotics for children with lower respiratory tract infection in Guizhou People’s Hospital was 56.9%,39.08% and 4.02% respectively.4.Measures on COVID-19 prevention and control effectively blocked the spread of pathogenic bacteria and reduced the infection rate of related respiratory pathogens.