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Objective To evaluate the clinical performance of the BACTEC Plus aerobic,BACTEC Lytic anaerobic,BacT/Alert aerobic and anaerobic blood culture media in detection of bloodstream infections.Methods Retrospective study was conducted.A total of four blood culture bottles from each inpatient with suspected bloodstream infections were collected and analyzed from June 2013 to September 2015 in Peking University People's Hospital.The four bottles,including BACTEC Plus aerobic,BACTEC Lytic anaerobic,BacT/Alert FA aerobic and BacT/Alert FN anaerobic media,and was incubated for 5 days in the BacT/Alert 3D and BACTEC FX instruments,respectively.Time to detection (TTD) and positive rate in detecting bacteria of the two systems were evaluated by Wilcoxon test and Chi-square test.Results Among 2 189 total cultures collected,20 were excluded because of blood shortage and 201 (9.27％) were positive for pathogens.The positive rates of BACTEC Plus aerobic media and BacT/Alert FA aerobic media were 75.3％ (140/186) and 69.4％ (129/186) (x2 =1.625,P=0.202),respectively.While,the positive rates of BacT/Alert FN anaerobic media and BACTEC Lytic anaerobic media were 81.8％ (99/121) and 63.6％ (77/121) for total organisms,respectively (x2 =10.083,P =0.001).A significant difference in TTD was detected in BACTEC Plus aerobic media[11.0 (8.0-16.0) h] and BacT/Alert FA aerobic media[13.9 (10.4-18.7) h] (Z =-5.240,P ＜ 0.001).BACTEC Lyric anaerobic media[8.0(7.0-10.0) h] had a shorter TTD (Z =-4.299,P ＜ 0.001) than BacT/Alert FN anaerobic media[11.3(9.3-12.7) h].The positive rates of BACTEC and BacT/Alert system were 74.13％ (149/201) and 74.63％ (150/201),respectively,compared with taking one set from each system.Conclusions BACTEC media has a shorter TTD and almost the same bacterial recovery,and lower false positive rate than the BacT/ Alert media.
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Objective To investigate the factors affecting the susceptibility of tigecycline and assess the testing methods.Methods The 116 isolates of Acinetobacter baumanaii and Klebsiella pneumoniae were collected in 13 hospitals from January to December,2010,to evaluate the effects on the tigecycline susceptibility of the overnight medium,medium brand and lot number,respectively.The 56 isolates of Acinetobacter baumannii and the 47 isolates of Klebsiella pneumoniae were selected randomly according to the MIC distribution proportion in 2010 and 2012.The broth microdilution was taken as the reference method to evaluate the effects of the agar dilution,disk diffusion,MIC Test Strip (MTS) and Vitek2 (GN16) on the susceptibility of tigecycline.Results The essential agreement (EA) of Acinetobacter baumannii and Klebsiella pneumoniae is 89.7％ (52/58)and 87.9％ (51/58) using overnight medium and fresh medium respectively.Both EA and categorical agreement (CA) of the different brands (BBL and Oxoid) and lot numbers are 100％ using agar dilution.According to the FDA break point criteria,the CA/EA is 77.7％ (80/103)/99.0％ (102/103),87.4％ (90/103)/98.1％ (101/103),64.1％ (66/103)/76.7％ (79/103) using agar dilution,MTS,Vitek (GN16) with respect to broth microdilution.The CA is 79.6％ (82/ 103,S≥14 mm,R≤10 mm),69.9％ (72/103,S≥ 16 mm,R≤ 12 mm),34.0％ (35/103,S≥19 mm,R≤14 mm)using disk diffusion method compared with broth microdilution (FDA break point criteria).Conclusions The susceptibility of tigecycline must be tested using fresh medium.The medium brands and lot numbers used in this test have no effects on the tigecycline susceptibility to Acinetobacter baumannii and Klebsiella pneumoniae.There exist the better correlations on MIC using agar dilution and MTS than the disk diffusion and Vitek(GN16) compared with broth microdilution.It is expected that the consistency can be improved by adjusting the break point of disk diffusion.
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).The complication rate in RIVVH was lower than that in the control group (P<0.05).Conclusions Early RIVVH was effective in the treatment of SAP,and may be an option as adjuvant treatment measure.