Etiology Of 2335 Children With Community Acquired Pneumonia In Handan Area Were Reviewed Retrospectively

Objective:To understand the pathogen distribution of Community acquired pneumonia(CAP)in children in Handan area and the drug resistance of common pathogens,so as to provide reference data for the treatment of CAP in children and improve the ability of treatment of CAP in children in this area.Methods:In this study,2335 children who were hospitalized in the pediatric ward of Handan Central Hospital from January 2019 to December2020 and met the CAP diagnostic criteria in the"Norms for the Treatment of Children with Community-acquired Pneumonia(2019 Edition)"and received sputum culture examination were selected as the study objects.The cases of children were reviewed through the electronic medical record management system,and the clinical features(including sex,age,length of stay),physical examination of pathogens and drug sensitivity test results of common pathogens of all children were gathered.The children were divided into four groups according to age,namely the infant group(>28 days～≤1 years old),the infant group(>1 years～≤3 years old),the preschool group(>3 years～≤6 years old),and the school age group(>6～≤14 years old).The forms of pathogens and mixed infections in different age structures and seasons were counted,and the Chi-square test was used to compare the differences.Results:1.Epidemiological characteristics:There were 1399 males and 951females in hospitalized children with CAP,with a male-to-female ratio of1.47:1.There were 804 samples(34.43%)in the infant group,673 samples(28.82%)in the infant group,596 samples(25.52%)in the preschool group and 262 samples(11.23%)in the school-age group.There were 301 cases(12.89%)in spring,246 cases(10.54%)in summer,662 cases(28.35%)in autumn,and 1126 cases(48.22%)in winter.2.Among 2335 hospitalized children with CAP,at least one pathogen was detected in 1412 cases,with a detection rate of 60.47%.Among them,single pathogen infection was dominant,accounting for 49.03%(1145/2335),and mixed pathogen infection(≥two or more pathogens)accounted for 11.43%(267/2335).Mycoplasma pneumoniae(23.21%),virus(19.19%),bacteria(6.25%),and Chlamydia pneumoniae(0.39%)were the most common pathogens.Among the mixed pathogen infections,239 cases were co-infected with two pathogens,28 cases were co-infected with three pathogens,and 0cases were co-infected with four pathogens.3.Pure mycoplasma pneumoniae,a single virus,the single bacterial infection caused by CAP are statistically significant differences in different age groups(χ~2=94.055,χ~2=58.021,χ~2=12.834,P<0.05).Mycoplasma pneumoniae infection was the highest in the school-age group(40.80%),followed by the preschool group(33.85%).The virus was more prevalent in the infant group(25.12%),followed by the infant group(20.06%).Bacteria were more common in infants(17.14%).4.pure mycoplasma pneumoniae,a single virus infection caused by CAP in different seasons of the difference was statistically significant(χ~2=70.561,χ~2=57.888,P<0.05).Single bacterial infection caused by CAP there was no statistically significant difference in different seasons(χ~2=6.791,P>0.05).In this study,mycoplasma pneumoniae infection was the most common in winter(29.57%),followed by autumn(22.36%).Viral infections occur more frequently in winter(24.51%).5.Among mixed pathogen infections,CAP children were most commonly infected by two pathogens(89.51%,239/267),among which virus+bacteria(32.64%,78/239)was the highest,followed by virus+MP(30.13%,72/239)and bacteria+MP(27.20%,65/239).There were statistically significant differences in viral+bacterial infection in different age groups and seasons(χ~2=17.078,χ~2=11.941,P<0.05);There was no significant difference in virus+MP infection among different age groups(χ~2=2.076,P>0.05),the difference was statistically significant in different seasons(χ~2=57.888,P<0.05);The difference of bacterial+MP infection in different age groups was statistically significant(χ~2=25.624,P<0.05),there was no significant difference between different seasons(χ~2=6.791,P>0.05).6.In this study,the positive rate of virus detection was 26.93%(629/2335),among which influenza virus(including type A and B)was the most common 41.81%(263/629),followed by respiratory syncytial virus38.00%(239/629),parainfluenzae virus and adenovirus were not common.There was no statistically significant difference in different age groups(χ~2=5.474,P>0.05).Respiratory syncytial virus infection was statistically significant in all age groups(χ~2=65.515,P<0.05),more common in infants.7.A total of 344 strains of bacteria were detected in 325 bacteria-positive cases,mainly Gram-negative bacteria(52.04%).The top five were Streptococcus pneumoniae(23.25%),Staphylococcus aureus(18.90%),Haemophilus influenzae(15.70%),Klebsiella pneumoniae(12.80%)and Escherichia coli(12.21%).8.Drug resistance of common bacteria:Among gram-positive bacteria,Streptococcus pneumoniae had high resistance to penicillin,erythromycin and clindamycin,and the resistance rates were 88.75%,83.75%and 79.75%,respectively.The resistance rate to cefepime was very low,and the resistance rate was 2.50%.Staphylococcus aureus had high resistance to penicillin and azithromycin,and the resistance rates were 95.38%and 76.92%,respectively,and low resistance to cotrimoxazole and tetracycline(16.92%,12.30%),No resistant strains to vancomycin,linezolid,rifampicin and levofloxacin were detected in these two strains.Among gram-negative bacteria,Haemophilus influenzae showed high resistance to amoxicillin/clavulanate,ampicillin and cotrimoxazole,with resistance rates of 90.74%,87.04%and 79.63%,respectively.No drug-resistant strains were detected for ceftriaxone,cefotaxime,cefuroxime,levofloxacin and imipenem.Klebsiella pneumoniae and Escherichia coli had high resistance to ampicillin,with resistance rates of90.09%and 85.71%,respectively.No resistant strains to imipenem were detected.Conclusion:1.In hospitalized children with CAP,single pathogen infection is the main infection,among which the most common is mycoplasma pneumoniae infection,which mostly occurs in school-age children,usually in autumn and winter;The second is viral infection,more common in infancy children,tend to occur in winter.2.Mixed infection is more common with the two pathogens,among which the highest proportion was viral and bacterial infection,which was more common in the infant group and occurred in winter;Secondly,virus+MP infection was more likely to occur in winter,and there was no statistical significance in different age groups.Bacterial+MP infection was more common in pre-school age group,and there was no statistical significance in different seasons.3.Influenza virus is the most common viral infection,followed by respiratory syncytial virus.There is no significant difference between the former and the latter in infancy.4.The bacterial infections in this region were mainly gram-negative bacteria,among them,mainly Haemophilus influenzae,Klebsiella pneumoniae and Escherichia coli,which were highly resistant to ampicillin and highly sensitive to imipenem.Common gram-positive bacteria are Streptococcus pneumoniae and Staphylococcus aureus,which are highly resistant to penicillin and erythromycin,and highly sensitive to vancomycin,linezolid and rifampicin.