OBJECTIVE To study the carbapenemase genotypes among Acinetobacter calcoaceticus isolates infected after liver transplantation. METHODS The 5.4 software was used to analyze the resistance of Acinetobacter species. Eight strains of imipenem-resistant A. calcoaceticus which were resistant to multiple drugs were collected. Analytical isoelectric focusing electrophoresis was used to measure the pI of the ?-lactamase. The homology of the isolates was determined by pulsed field gel electrophoresis(PFGE). blaTEM, blaSHV, blaIMP, blaVIM, blaOXA Genes for resistant isolates were amplified and sequenced. RESULTS Imipenem-resistant A. calcoaceticus infected after liver transplantation was resistant to multiple drugs. All of 8 strains were produced OXA-23 carbapenemases (pI of 6.7). The results of PFGE indicated there was a trend of resistant clone transmisstion in the transplantation ward. CONCLUSIONS There is a transmisstion of A. calcoaceticus producing OXA-23 carbapenemase in the transplantation ward of our hospital. It is important to monitor powerfully the bacterial resistance to control infection more effectively.

Objective To evaluate analytical performance of homocysteine (Hcy) by circulating enzymatic method .Methods Re‐ferring to CLSI evaluation project and pertinent literature ,and by combining our actual works .we designed a verification procedure and experimental method .By using these above ,the precision ,accuracy ,analytical measurement range ,clinical reportable range of Hcy by circulating enzymatic method were evaluated .Results would be compared with the declaration of the manufacturer (NingBo Medical System Biotechnology Co .,Ltd) or desirable specifications derived from biologic variation .Results The results showed that the within‐run CV were 1 .26% and 0 .84% ,and the total CV were 1 .36% and 1 .32% ,less than 10% of the manufacturer′s statement .The relative bias between the results measured for calibrator at tow levels and target value was 3 .69% and 0 .69% ,less 10% .AMR was 3 .38-51 .81 μmol/L ,and the most suitable dilution rate was 1∶3 ,so the CRR was 3 .38-155 .43 μmol/L .Con‐clusion The analytical performance of Hcy analyzed by circulating enzymatic method is consistent with the standards which manu‐facturers has proclaimed ,so it is conform to the requirements of clinical .