ABSTRACT
BACKGROUND: Introduction of automation instruments for the blood bank is essential in order to reduce inspection error and minimize workload. We compared the results of ABO-RhD blood type and antibody screening tests using the manual method and those using the automation instruments AutoVue Innova (Ortho-Clinical Diagnostics, Raritan, NJ, USA) and QWALYS-3 (DIAGAST, Loos Cedex, France). METHODS: ABO-RhD blood type tests using the slide method, the tube method, and the instruments were performed with 200 selected samples. Antibody screening tests using the Ortho BioVue system (Ortho-Clinical Diagnostics, Raritan, NJ, USA), which is used in our laboratory, and the two instruments were performed with 188 specimens and 12 antibody positive samples that were kept in the laboratory. We evaluated the concordance rate of the results, applying CLSI guideline EP12-A2. RESULTS: The concordance rate of ABO-RhD blood type results between the manual methods and the two instruments was 100%. On antibody screening tests, a concordance rate of 100% was observed between the manual method and AutoVue Innova, which uses the gel card manufactured by the company making the gel card used for the manual method. However, using QWALYS-3 in performance of antibody screening tests, the concordance rate was 97.5%, because of discordance in five specimens. CONCLUSION: The concordance rate of ABO-RhD blood type by use of two automation instruments was 100%, however, that of the antibody screening test was 97.5%. Thus, there was a difference in positive rate on the antibody screening test, depending on the instrument. Therefore, introduction of an instrument, considering the pros and cons for each instrument, is necessary. In addition, further discussion of standardized guidelines for quality control is needed.
Subject(s)
Automation , Blood Banks , Cephalosporins , Mass Screening , Quality ControlABSTRACT
We have isolated 6 vancomycin resistant (VR) Enterococcus faecium and 5 VR-E. gallinarum. Vancomycin resistant enterococcus (VRE) isolates were resistant to multi-drugs, but susceptible to linezolid and quinupristin/dalfopristin. VRE isolates showed 10 VanA phenotypes and 1 VanB phenotype (E. gallinarum). However, all of them showed vanA genotype. vanA gene was detected on both genomic and plasmid DNA from all VRE isolates. Almost of VR-E. faecium had IS1216V which is worldwide type and almost of VR-E. gallinarum had IS1542 which is European type. IS1216V and IS1542 genes were not related with antibiotic types of VRE. Copy numbers of vanA were decreased in VRE with IS1216V or IS1542 but not in VRE with both ISs in broth without vancomycin. The copy numbers of vanA were significantly decreased in VanB phenotype of VRE with IS1542 in broth without vancomycin. Copy numbers of vanA were recovered in the presence of vancomycin. Growth time of reference E. faecium is faster than that of reference E. faecalis when cultured in the broth containing vancomycin. Reference strains cultured in the broth containing vancomycin showed intermediate resistance or resistance to antibiotics without acquisition of van genes. Naturally, multidrug-resistant E. faecium might be fast adapted in the presence of vancomycin compared to E. faecalis. Taken together, VanA phenotype E. gallinarum as well as E. feacium have been increasing in nosocomial infection and showed acquired inducible resistance. E. faecium and E. faecalis showed intermediate resistance in long exposure of vancomycin without acquisition of vanA.