Preliminary Investigation Of Pathogenic Bacteria And Drug Resistance Of Severe Community-acquired Pneumonia

ObjectiveTo investigate the distribution and drug resistance of pathogenic bacteria in sputum of patients with severe community-acquired pneumonia,and to provide reference for rational use of clinical antibacterial drugs.Methods623 patients with severe community-acquired pneumonia from January 1,2015 to December 31,2018 who were admitted to The 97 th hospital of the joint logistic support force of the Chinese people's liberation army,were selected to collect sputum culture and drug sensitivity data for retrospective analysis.At the same time,relevant factors(such as age,season,department,etc.)that may affect the distribution of pathogenic bacteria and drug resistance of patients were also summarized and analyzed.Result1.Among the 623 patients with severe community-acquired pneumonia in our hospital,168(27.0%)were sputum culture positive and 455(73.0%)were sputum culture negative.A total of 192 strains were cultured,including 176 gram-negative strains,mainly klebsiella pneumoniae,pseudomonas aeruginosa and acinetobacter baumannii.There were 16 gram-positive strains,including staphylococcus aureus,staphylococcus haemolyticus and enterococcus faecalis.2.Acinetobacter baumannii was generally resistant to pi-lactam/pi-lactamase inhibitors,third-generation and fourth-generation cephalosporins,quinolones and carbapenem antibiotics,and the drug resistance rate was more than 60%;It is relatively sensitive to cotrimoxazole,but the drug resistance rate is more than 40%.No strain resistant to minocycline and polymyxin B was found.The detection rate of carbapenems resistant klebsiella pneumoniae(CRKP)in klebsiella pneumoniae was16.1%;The drug resistance rate of first-generation and second-generation cephalosporins was more than 40%.The drug resistance rate to the third and fourth generation cephalosporins was more than 30%;The drug resistance rates of minocycline and amikacin were 12.5% and 17.9%,respectively.The resistance rate of pseudomonas aeruginosa to third and fourth generation cephalosporin antibiotics was more than 20%.The drug resistance rate to beta-lactam/beta-lactamase inhibitors was more than 30%.Resistance to carbapenem antibiotics was high,with the drug resistance rates of imipenem and meropenem being 52.2% and 39.1%,respectively.The most sensitive to polymyxin,the drug resistance rate was only14.5%.The drug resistance rate of staphylococcus aureus to clindamycin,erythromycin and penicillin was more than 80%.The resistance rate to levofloxacin was more than 50%,and the resistance rate to chloramphenicol was 8.3%.No staphylococcus aureus resistant to tetracycline,tigacycline,linezolid,amikacin and vancomycin were found.The drug resistance rate of staphylococcus haemolyticus to penicillin and levofloxacin was 100%.Tetracycline,clindamycin is relatively sensitive,drug resistance rate is less than 40%.No hemolytic staphylococci resistant to tigacycline,linezolid,vancomycin,amikacin and chloramphenicol were found.3.The detection rates of major pathogens did not change significantly in the last4 years.There was no significant difference in the detection rates of major gram-negative bacteria and major gram-positive bacteria in the same year and season.The detection rates of pseudomonas aeruginosa were significantly different in different seasons,and were higher in autumn.4.The positive rates of sputum bacteria culture in the wards of the old cadres,ICU and general wards were 27.8%,49.4% and 21.4% respectively.The detection rate of gram-negative bacteria(acinetobacter baumannii,klebsiella pneumoniae and pseudomonas aeruginosa)in ICU ward was significantly higher than that in the ward of veteran cadres and the general ward,and the general ward was the lowest;The detection rate of pseudomonas aeruginosa was higher than that of klebsiella pneumoniae;The detection rate of klebsiella pneumoniae in general wards was significantly higher than that of acinetobacter baumannii and pseudomonas aeruginosa.The detection rates of major gram-positive bacteria(staphylococcus aureus and staphylococcus haemolyticus)were not significantly different in different departments.5.The positive rate of sputum culture increased with age,and the detection rate of pseudomonas aeruginosa was highest in patients aged ? 90 years..There was no significant difference in the detection rates of acinetobacter baumannii,klebsiella pneumoniae,staphylococcus aureus and staphylococcus haemolyticus in different age groups.ConclusionThe pathogenic bacteria of severe community-acquired pneumonia patients were mainly gram-negative bacteria,mainly klebsiella pneumoniae,pseudomonas aeruginosa and acinetobacter baumannii.Gram-positive bacteria also accounted for a certain proportion,mainly staphylococcus aureus.The detection rate of pseudomonas aeruginosa in autumn was significantly higher than that in other seasons.There was no significant difference in the detection rate of major pathogens in different years.The positive rate of sputum bacteria culture and the detection rate of main gram-negative bacteria(acinetobacter baumannii,klebsiella pneumoniae and pseudomonas aeruginosa)in ICU ward were higher than that in general ward and old cadre ward,and the general ward was the lowest;The detection rate of pseudomonas aeruginosa was higher than that of klebsiella pneumoniae;The detection rate of klebsiella pneumoniae in general wards was significantly higher than that of acinetobacter baumannii and pseudomonas aeruginosa.The positive rate of sputum culture increased with age,and the detection rate of pseudomonas aeruginosa was highest in patients aged ? 90 years.