Abstract:

Objective To analyze the distribution and drug resistance of isolates from blood culturing in Shandong,and to provide a reference for the treatment of bloodstream infection. Methods The isolates from blood culturing were collected and analyzed retrospectively from January 2015 to December 2015 in Shandong. The results were assessed according to the Clinical and Laboratory Standards Institute （CLSI）2014 standard,and WHONET 5.6 software was used for drug resistance analysis. Results In the 17 361 isolates,Gram-negative bacilli accounted for 54.9% （9 524 isolates）,and its isolation rate was higher than that of Gram-positive cocci（accounting for 45.1%,7 837 isolates）. The top 5 isolates were Escherichia coli,coagulase-negative Staphylococcus,Klebsiella pneumoniae,Staphylococcus aureus and Pseudomonas aeruginosa. The isolation rates of extended-spectrum beta-lactamases （ESBLs）-producing Escherichia coli and Klebsiella pneumoniae were 53.5% and 25.8%,respectively. The drug resistance rates of ESBLs-producing isolates to carbapenems,oxygenase inhibitors and cephalosporin were lower. The drug resistance rates to carbapenems in Pseudomonas aeruginosa and Acinetobacter baumannii were high,and carbapenems should be chosen to use carefully. The determination rate of methicillin-resistant Staphylococcus aureus （MRSA） was 27.1%,which was less than that of methicillin-resistant coagulase-negative Staphylococcus （MRSCNS,80.2%）. No Staphylococcus resistant to vancomycin and linezolid was found. The drug resistance rates of Enterococcus faecium and Enterococcus faecalis to vancomycin were 1.7% and 1.2%,and those to linezolid were 0.7% and 4.7%. Vancomycin can be still as the first choice for Gram-positive cocci in bloodstream infection. Conclusions The analysis on the distribution and drug resistance of isolates from blood culturing could guide the rational use of medicines in clinic and reduce the mortality in severe infection.

Key words: Pathogenic bacteria, Drug resistance rate, Blood culturing, Bloodstream infection