Etiology and Resistance in Bloodstream Infections in Hangzhou Area

OBJECTIVE To determine the bacterial distribution and resistance of bloodstream infections in Hangzhou area.METHODS Records of positive blood culture from 2004 to 2008 in Hangzhou area were examined.According to the CDC definition of bloodstream infection,the bloodstream infections were diagnosed.The bacterial isolates were tested by K-B susceptibility,the outcome of distribution features and antibiotic sensitivity of isolates were analyzed.RESULTS A total of 397 episodes were diagnosed and 405 pathogenic isolates were collected.Gram-positive strains,Gram-negative strains and fungi accounted for 38.5%,55.8% and 5.7%,respectively.The commonest pathogens causing bloodstream infections were coagulase-negative staphylococcus(CNS)(22.7%),followed by Escherichia coli(13.8%).The susceptibility tests in vitro showed that 70.7% and 29.4% of S.aureus and CNS were meticillin-resistant.No Staphylococcus strain was resistant to vancomycin.The ESBLs positive rate of E.coli was 48.2%.The resistant rate of Pseudomonas aeruginosa to imipenem was 33.3%,while none of E.coli and Klebsiella were resistant to imipenem.All of the three were high susceptible to piperacillin/tazobactam and cefoperazone/sulbactam,but their resistant rates to SXT,cefotaxime and ampicillin/sulbactam were also high.CONCLUSION Gram-negative bacteria are the predominant pathogens and CNS are the most common pathogens to cause bloodstream infection in Hangzhou area.Drug resistance of Gram-negative bacteria is serious.Monitoring the change of pathogen and the trends of antimicrobial resistance is important in guiding clinical drug application.