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A study was conducted to evaluate the new VITEK 2 system (bioMérieux) for identification and antibiotic susceptibility testing of gram-positive cocci. Clinical isolates of Staphylococcus aureus (n ‫؍‬ 100), coagulasenegative staphylococci (CNS) (n ‫؍‬ 100), Enterococcus spp. (n ‫؍‬ 89), Streptococcus agalactiae (n ‫؍‬ 29), and Streptococcus pneumoniae (n ‫؍‬ 66) were examined with the ID-GPC identification card and with the AST-P515 (for staphylococci), AST-P516 (for enterococci and S. agalactiae) and AST-P506 (for pneumococci) susceptibility cards. The identification comparison methods were the API Staph for staphylococci and the API 20 Strep for streptococci and enterococci; for antimicrobial susceptibility testing, the agar dilution method according to the procedure of the National Committee for Clinical Laboratory Standards (NCCLS) was used. The VITEK 2 system correctly identified to the species level (only one choice or after simple supplementary tests) 99% of S. aureus, 96.5% of S. agalactiae, 96.9% of S. pneumoniae, 92.7% of Enterococcus faecalis, 91.3% of Staphylococcus haemolyticus, and 88% of Staphylococcus epidermidis but was least able to identify Enterococcus faecium (71.4% correct). More than 90% of gram-positive cocci were identified within 3 h. According to the NCCLS breakpoints, antimicrobial susceptibility testing with the VITEK 2 system gave 96% correct category agreement, 0.82% very major errors, 0.17% major errors, and 2.7% minor errors. Antimicrobial susceptibility testing showed category agreement from 94 to 100% for S. aureus, from 90 to 100% for CNS, from 91 to 100% for enterococci, from 96 to 100% for S. agalactiae, and from 91 to 100% for S. pneumoniae. Microorganism-antibiotic combinations that gave very major errors were CNS-erythromycin, CNS-oxacillin, enterococci-teicoplanin, and enterococci-high-concentration gentamicin. Major errors were observed for CNS-oxacillin and S. agalactiaetetracycline combinations. In conclusion the results of this study indicate that the VITEK 2 system represents an accurate and acceptable means for performing identification and antibiotic susceptibility tests with medically relevant gram-positive cocci.Automation in clinical microbiology is still in a very early stage of development compared with the level of automation that has been achieved in clinical chemistry, hematology, and immunology laboratories.In the last 20 years, a variety of automated systems for the identification and antimicrobial susceptibility testing (AST) of microorganisms has been developed based on automated interpretation of the results of biochemical tests or using microdilution trays following overnight incubation and photometric determination of growth (6,18,20,21). Advances in technology that may provide rapid bacterial identification and AST are now recognized as having both clinical and financial benefits (2).The VITEK system originated in the 1970s as an automated system for identification and AST and has evolved today into the VITEK 2 system, which automatically performs ...

Purpose-To compare organ specific cancer incidence risks for standard and complex external beam radiotherapy including cone beam CT verification following breast conservation surgery for early breast cancer.Method-Doses from breast radiotherapy and kilovoltage cone beam CT (CBCT) exposures were obtained from thermoluminescent dosimeter (TLD) measurements in an anthropomorphic phantom in which the positions of radiosensitive organs were delineated. Five treatment deliveries were investigated : (i) conventional tangential field whole breast radiotherapy (WBRT), (ii) noncoplanar conformal delivery applicable to accelerated partial beast irradiation (APBI), (iii) twovolume simultaneous integrated boost (SIB) treatment, (iv) forward planned three-volume SIB, (v) inverse-planned three volume SIB. Conformal and intensity modulated radiotherapy (IMRT) methods were used to plan the complex treatments. Techniques spanned the range from simple methods appropriate for patient cohorts with a low local cancer recurrence risk to complex plans relevant to cohorts with high recurrence risk. Delineated organs at risk included brain, salivary glands, thyroid, contra-lateral breast, left and right lung, oesophagus, stomach, liver, colon and bladder. Biological Effects of Ionising Radiation (BEIR) VII cancer incidence models were applied to the measured mean organ doses to determine Lifetime Attributable Risk (LAR) for ages at exposure from 35 to 80 years according to radiotherapy techniques, and included dose from the CBCT imaging.Results-All LAR decreased with age at exposure and were lowest for brain, thyroid, liver and bladder (< 0.1%). There was little dependence of LAR on radiotherapy technique for these organs and for colon and stomach. LAR values for the lungs for the three SIB techniques were two to three times those from WBRT and APBI. Uncertainties in the LAR models outweigh any differences in lung LAR between the SIB methods. Constraints in the planning of the SIB methods ensured that contra-lateral breast doses and LAR were comparable to WBRT, despite their added complexity. The smaller irradiated volume of the ABPI plan contributed to a halving of LAR for contralateral breast compared with the other plan types. Daily image guided radiotherapy (IGRT) Europe PMC Funders Author ManuscriptsEurope PMC Funders Author Manuscripts for a left breast protocol using kilovoltage CBCT contributed <10% to LAR for the majority of organs, and did not exceed 22% of total organ dose.Conclusion-Phantom measurements and calculations of LAR from the BEIR VII models predict that complex breast radiotherapy techniques do not increase the theoretical risk of second cancer incidence for organs distant from the treated breast, or the contralateral breast where appropriate plan constraints are applied. Complex SIB treatments are predicted to increase the risk of second cancer incidence in the lungs compared to standard whole breast radiotherapy ; this is outweighed by the threefold reduction in 5 year local recurrence risk for patie...