Abstract:

Objective To investigate and analyze the distribution of pathogenic bacteria, drug resistance and change trend of patients infected in the Intensive Care Unit (ICU) of our Hospital, to compare to the China Antimicrobial Surveillance Network for a clinical guidance of the rational use of antibiotics. Methods A retrospective study was performed to statistically analyze on the drug susceptibility results of pathogenic bacteria isolated from specimens of ICU patients from 2019 to 2021. Results A total of 2 088 strains of bacteria including 1 463 strains of bacteria for lower respiratory tract (70.1%), 211 strains of bacteria for blood (10.1%) and 115 strains of bacteria for midstream urine (5.5%) were collected and isolated. In the 2 088 strains of bacteria, there were 1 483 gram-negative bacilli (accounting for 70.1%), 527 gram-positive bacilli (accounting for 25.2%) and 78 fungi (accounting for 3.7%). The top four gram-negative bacilli were Klebsiella pneumoniae, Acinetobacter baumannii, Escherichia coli and Pseudomonas aeruginosa. The top three gram-positive bacteria were Staphylococcus aureus, Enterococcus faecium and faecal enterospherus. The fungi were mainly Candida albicans. The maximum drug resistance to carbapenems were Acinetobacter baumannii, followed by Pseudomonas aeruginosa, Klebsiella pneumoniae and Escherichia coli. The resistance rate of Acinetobacter baumannii to carbapenem increased significantly, exceeding 80%. The resistance rate of pseudomonas aeruginosa to carbapenem was close to or more than 20%.The isolation rate of Klebsiella pneumoniae had been on the rise since 2020, accounting for the first place, its drug resistance rate against carbapenem was less than 20%, and Escherichia coli was sensitive to carbapenem. Staphylococcus aureus resistant to oxacillin was 27.3%-34.5%, and no linezolid, vancomycin or tigecycline resistance was found to be drug resistant. Conclusion The main pathogenic bacteria sources of patients from ICU of the Hospital are the bacteria for lower respiratory tract infection, followed by the bacteria for bloodstream infection and urinary tract infection. Pathogenic bacteria are mainly composed of Gram-negative bacilli, followed by Gram-positive bacteria and fungi. The growth trend of drug resistance shows increment growth, and the separation rate and drug resistance rate of extended-spectrum β-lactamase and carbapenem-resistant Klebsiella pneumonia are lower than the data of China Antimicrobial Surveillance Network, the drug resistance rate of Acinetobacter baumannii to carbapenem is higher than the data of China Antimicrobial Surveillance Network, and the drug resistance of other bacteria is basically equivalent to national level. The drugs selected for clinical practices shall follow nosocomial drug sensitivity results.

Key words: intensive care unit, drug resistance, bacteria, antibiotics