Analysis of distribution and drug resistance of common pathogenic bacteria in blood culture

Objective To investigate the distribution of pathogenic bacteria in blood culture and to observe the drug resistance of common pathogens in our hospital to provide the basis for clinical antimicrobial therapy.Methods BACTEC9120 system made by BD company was applied for the blood culture.The microorganism identification and antimicrobial resistance tests were performed with the BD phoenix100 system.Results Among 2978 blood culture samples,317 cases were alarm positive with the positive rate of 10.6%.Among 170 strains first isolated from the patient,Gram-negative bacteria were dominated,total 111 strains accounted for 65.3%,46 strains were Gram-positive(27.1%) and 13 strains were fungi(7.6%).Among Gram-negative bacteria,Escherichia coli was dominated,accounting for 28.8% of the total isolates and 44.1% of Gram-negative bacteria.Among Gram-positive bacteria,coagulase-negative staphylococcus was dominated.The detection rates of extended spectrum β lactamase(ESBLs) producing in Gram-negative bacteria Escherichia coli and Klebsiella pneumonia were 44.9% and 23.1% respectively,showing high antibacterial activity to meropenem and imipenem with the sensitive rate of 100%.Pseudomonas aeruginosa revealed the high resistance to ampicillin,ampicillin/sulbactam,cefazolin,cephalosporins,chloromycetin,tetracycline and compound sulfa drugs and high sensitivity to other drugs.The methicillin-resistant rates of Staphylococcus aureus and coagulase-negative staphylococcus were 30.0% and 95.4% respectively,strains resistant to vancomycin and linezolid were not found.Conclusion Hospital should strengthen the monitoring of blood culture,find pathogens as early as possible,monitor the distribution change and drug resistance change trend of pathogenic bacteria in time to provide the basis for clinical diagnosis and treatment.