Distribution and drug resistance of pathogenic bacteria isolated from Intensive Care Units

Objective To investigate the distribution and the resistance rates of bacteria isolated from intensive care units(ICUs) in the First Affiliated Hospital of Zhejiang Chinese Medical University and compare with those isolated from non-ICUs,and provide valuable reference for clinical medication.Method The samples from January 2010 to June 2011 were collected.Strains were identified with VITEK-2 compact,and GPI,GNI,ANC,YST,AST-GN13,AST-GP67 were used to detect strains,respectively.The resistance to antimicrobial agents were tested according to the guidelines of CLSI(2010).Result A total of 2 341 strains were isolated,21.6% of which were from ICUs while 78.4% from non-ICUs.Of the strains from ICUs,23.2%(117/505) was Gram-positive bacteria,47.3%(239/505) was non fermenters bacteria.Of the strains from non-ICUs,34.4%(632/1836) was Gram-positive bacteria,20.2%(371/1836) was non fermenters bacteria.The most common pathogens from ICUs were Acinetobacter baumanni,Klebsiella pneumonia and Burkholderia cepacia,while those from non-ICUs were Escherichia coli,Staphylococcus aureus and Pseudomonas aeruginosa.The resistant rates of Acinetobacter baumanni and Pseudomonas aeruginosa to Piperacillin/Tazobactam,Ceftazidime,Cefepime,Imipenem and Meropenem were significantly different between ICUs and non-ICUs.The MIC50 values of the isolates from ICUs to Imipenem were 8 times higher than those from non-ICUs,but the MIC90 values were similar.The resistance rate of S.aureus from ICUs to Cefazolin,Ciprofloxacin and Levofloxacin were significantly higher than those from non-ICUs(P0.05).Staphylococcus were sensitive to Vancomycin,Teicoplanin and Linezolid in both ICUs and non-ICUs.Conclusion Most of the pathogenic bacteria isolated from ICUs are Gram-negative bacteria,with non-fermentation bacteria being dominant.The incidence rate of Gram-positive bacteria from non-ICUs are higher than that from ICUs.Among the major pathogenic bacteria,the resistant rates of bacteria isolated from ICUs are significantly higher than those from non-ICUs.