Bacteria Isolated From Sputum Samples Of MICU Elderly Patients With Lower Respiratory Tract Infection And Changes In Drug Resistance Rates

Objective:The main pathogenic bacteria isolated from the sputum samples of elderly inpatients in the MICU in our hospital and the changes of drug resistance rate were analyzed,so as to provide reference for future clinical medication.Methods: The eligible sputum samples were collected from elderly patients with lower respiratory tract infection aged over 60 years in the MICU in our hospital from January2017 to December 2019.Repeated pathogenic bacteria from the same patients were excluded.The bacterial strain isolation,culture identification and drug sensitivity test were carried out to observe and analyze the distribution of pathogenic bacteria and drug resistance results.Results:535 strains of pathogenic bacteria were isolated.Among them,there were 502 strains of Gram-negative bacilli,accounting for 93.8%,33 strains of Gram-positive cocci,accounting for6.2%,The first five common pathogenic bacteria were 161 strains of Acinetobacter baumannii(30.1%),135 strains of Pseudomonas aeruginosa(25.2%),86 strains of Klebsiella pneumoniae16.1%),35 strains of Stenotrophomonas maltophilia(6.5%)and 21 srrains of Staphylococcus aureus(3.9%).The drug resistance rate of Acinetobacter baumannii to a variety of antibiotics is high,and the drug resistance rate to carbapenems is more than 90%.During 2018-2019,the rate of doxycycline resistance decreased from 92.9% to 70.6%,with statistically significant differences(P<0.05),The drug resistance rate of minocycline decreased from 78.8% to 55.1% within 3 years;The drug resistance rate of Pseudomonas aeruginosa to piperacillin/tazobactam decreased from 40.5% to 17.9% year by year.The drug resistance rate of Klebsiella pneumoniae to amikacin,imipenem and meropenem decreased.The drug resistance rates of Stenotrophomonas maltophilia to cotrimoxazole,levofloxacin and minocycline were low,and no Staphylococcus aureus resistant to dactomycin,vancomycin,rifampicin and linezolid were found.Conclusion:Gram-negative bacilli were the main pathogens isolated from sputum samples of MICU elderly patients with lower respiratory tract infection in our hospital.The drug resistance of Acinetobacter baumannii was serious,and the decrease of the drug resistance rate to doxycycline was statistically significant.Other common pathogenic bacteria showed different degree of drug resistance to different common antibiotics.To analyze the distribution and drug resistance of sputum specimens,strengthen the continuous monitoring of drug resistance rate and reduce the iatrogenic infection,is of certain significance for guiding clinical rational drug use and reducing the infection rate of drug-resistant bacteria.