A Study On Pathogenic Distribution And Drug Resistance Of Patients With Low Respiratory Infection

Objective: Studies on pathogens of lower respiratory infection would be different as regions and scopes change.By taking the sputum specimens of patients in my hospital with lower respiratory tract infection as study objective,this paper conducted the bacterial culture and drug sensitive test.By analyzing lots of experiment results,the latest data on pathogenic microorganism distribution and drug-resistant characteristics was acquired.By comparing the latest distribution data and drug-resistance characteristics with the infection investigation report released by our hospital one year ago,changes of pathogenic bacterium distribution and drug-resistant characteristics were concluded,which were expected to provide some clinical reference and facilitate the proper use of antibiotics.Method and methodology: Sputum specimens of patients with lower respiratory tract infection from January 1st to December 31 st 2016 were collected and cultured.If three or more kinds of germs grew in one specimen,it was considered as sputum pollution.If there were two kinds of germs,the dominant bacteria was selected to conduct drug sensitivity test.French VITEK2-compact and DADE BEHRING automatic microorganism identification instrument were employed to conduct bacteria identification and antimicrobial susceptibility test.When necessarily,conventional biochemical method and K—B method were used for additional identification of all bacterial strains.Determination of results of antimicrobial susceptibility test were conducted according to Performance Standards for Antimicrobioal Susceptibility Testing in 2012.Results: 5743 sputum specimens were collected from January 1st,2016 to December31 st,2016.1379 were positive samples and the positive rates were 24%.The positive rates of bacterium: Pseudomonas aeruginosa(22%),Acinetobacter baumannii(17%),Klebsiella pneumoniae ss.Pne(14%),Escherichia coli(10%),Streptococcus pneumoniae(9%),Staphylococcus aureus ss.A(8%),Moraxella(Branh.)catarrhalis(4%),Candida albicans(2%),Enterobacter cloacae(2%),Enterobacter aerogenes(2%)and others(10%).Conclusions: The first five pathogenic bacterium of lower respiratory infection in 2016 were Pseudomonas aeruginosa,Acinetobacter baumannii,Klebsiella pneumoniae ss.Pne,Escherichia coli and Streptococcus pneumoniae.Compared with those in 2015,rates ofAcinetobacter baumannii increased greatly while Streptococcus pneumoniae reached the first five pathogenic bacterium.The drug resistance rates of pathogenic bacterium to ampicillin reached more than 80%.Thus,this antibiotic was not suitable for clinical application.Drug resistance effects of cefepime,tobramycin,levofloxacin,piperacillin/tazobactam,aztreonam,piperacillin,gentamicin,ticarcillin/clavulanate potassium and ciprofloxacin on pseudomonas aeruginosa infection.The most efficient drugs were ceftazidime,imipenem,meropenem and amikacin.Drug resistance test showed that acinetobacter baumannii was resistant to nearly all the antibiotics and isolation samples were almost from ICU.Thus,it was suggested that detection on ICU should be strengthened.Drug resistance of klebsiella pneumoniae was weak but its drug resistance to ampicillin was more than 80%.The most effective drugs for escherichia coli infection were ertapenem,imipenem,meropenem and amikacin.Ticarcillin/clavulanate potassium,piperacillin/tazobactam and cefoxitin were effective.As far as lower respiratory infection is concerned,rates and drug resistance of pathogenic bacterium would change as time goes by,which have correlation with principles and frequencies of antibiotics.Therefore,drug sensitivity test and analysis should be reinforced to provide scientific reference for proper clinic use of antibiotics.