Evaluation of ACCU-CHEK(R) Inform II Blood Glucose Meter and ACCU-CHEK(R) Performa Strip / 임상검사와정도관리

BACKGROUND: Self-monitoring of blood glucose levels is recommended for all diabetic patients who receive insulin treatment, because such monitoring of glucose levels may aid in achieving better control in type II diabetes. Further, the use of point-of-care (POC) blood glucose testing in hospitals has increased substantially. In the present study, we validated the performance of ACCU-CHEK(R) Inform II Blood Glucose Meter and ACCU-CHEK(R) Performa Strip (Roche Diagnostics, Germany). METHODS: We evaluated the precision, accuracy, and maltose interference of the ACCU-CHEK(R) Inform II Blood Glucose Meter and ACCU-CHEK(R) Performa Strip. Further, precision was evaluated using dedicated quality control (QC) and Bio-Rad Whole Blood (WB) QC materials (Meter Trax(TM) Control; Bio-Rad, USA). Forty samples were used to compare the results obtained using the ACCU-CHEK(R) Inform II Blood Glucose Meter and ACCU-CHEK(R) Performa Strip with those obtained using the clinical chemistry analyzer Hitachi 7600 (Hitachi, Japan). Maltose interference was assessed at 2 glucose concentration levels at 3 maltose concentration levels. RESULTS: For each concentration level of control materials, within-run coefficient of variation (CV) and total CV obtained were less than 5%. Good correlation was obtained using the Hitachi 7600 (y = 1.02x - 0.18; r 2 = 0.996; N = 40). Effects of maltose interference were less than 10%. CONCLUSIONS: Thus, the ACCU-CHEK(R) systems show good precision and correlation with the routine clinical chemistry analyzer and allow only minimal effects of maltose interference.

Creatinine Determination by Nova CCX Analyzer Harmonized with the Roche Enzymatic Method for Early and Accurate Detection of Renal Dysfunction

BACKGROUND: Early detection of underlying renal dysfunction among emergency patients is important, particularly before imaging studies using contrast media. The estimated glomerular filtration rate (eGFR) calculated from creatinine values is useful in situations requiring rapid evaluation and detection of renal impairment. METHODS: We evaluated the concordance of eGFR determined using the whole blood creatinine test by Nova CCX (Cr-CCX WB; Nova Biomedical, USA) method and the serum creatinine test by Roche Integra 800 (Cr-RE Serum; Roche Diagnostics, Switzerland) enzymatic method, which is known to be traceable to the isotope dilution mass spectrometric (ID-MS) reference method. RESULTS: Compared to Cr-RE Serum (x), Cr-CCX WB (y) showed good correlation but unacceptable total error and negative proportional bias (Deming regression, y=0.92x+0.02; r=0.98; n=61). However, when we adjusted the Cr-CCX WB values with a new slope and offset derived from the Deming regression analysis with Cr-RE Serum, the concordance rate improved from 0.77 to 0.93 (as measured by kappa statistics), and total errors became acceptable except at 1 level. When we used the ID-MS traceable eGFR formula, the Nova CCX demonstrated sufficient sensitivity (93.5%) and specificity (100%) for the detection of renal dysfunction (eGFR less than 60 mL/min/1.73 m2) in patients. CONCLUSIONS: We concluded that if we adjusted the harmonizing factors of Nova CCX according to the ID-MS traceable method, then the Nova CCX might be a relatively accurate point-of-care creatinine analyzer for detecting renal dysfunction among patients undergoing urgent imaging studies with radiological contrast media.

Sporicidal Activity of Selected Disinfectants against Clostridium difficile / 병원감염관리

BACKGROUND: Clostridium difficile infection (CDI) is the predominant cause of hospital-acquired diarrhea. This study evaluated the sporicidal activities of several disinfectants against C. difficile spores. METHODS: We used toxigenic C. difficile strains with different ribotypes for our study. We compared the sporicidal activities of Cavicide (Metrex Research Corporation, USA), Cidex OPA (Advanced Sterilization Products, USA), 1% Rely+On Virkon (Dupont, UK), 0.25% Surfanios (Laboratoires Anios, France), sodium hypochlorite (Yuhan Clorox, Korea), and 70% ethyl alcohol (Duksan, Korea) by using dilution-neutralization method. The sporicidal activity of the disinfecting agents was considered to be the inactivation factor (IF). The IF was calculated as the log10 colony forming unit (CFU) reduction of the viable count from the initial inoculums. Disinfectants were considered to be sporicidal if they showed an IF> or =4. RESULTS: Cavicide, 70% ethyl alcohol, Rely+On Virkon, and Surfanios showed no reduction in spore counts at all exposure time. Solutions of sodium hypochlorite diluted 1:100 (> or =400 ppm available chlorine), 1:50, and 1:20 were sporicidal after 5 min, 2 min, and 30 s, respectively. Cidex OPA showed sporicidal activity after 30 min. CONCLUSION: To prevent the transmission of CDI, at least 1,000 ppm sodium hypochlorite solution should be used to disinfect the hospital environment. Contaminated endoscopes should be disinfected with Cidex OPA for more than 30 min.

Reduction of the Platelet Transfusion Dose and Its Effects / 대한진단검사의학회지

BACKGROUND: In Korea, a platelet transfusion dose (TD) of 8 units of platelet concentrates (PC) is usually used. To minimize the shortage of blood products and transfusion-related adverse reactions, the TD has been changed from 8 to 6 units in 2006 in our hospital. Here, we analyzed the dose reduction effect on patients' platelet counts and transfusion frequency. METHODS: We compared the amount of issued PC, platelet counts before and after transfusion, post-transfusion platelet increments, and transfusion frequencies in patients who were transfused with 8 PC in 2006 and 6 PC in 2008. RESULTS: Despite an increase in the number of admitted patients by 20% in 2008 with a disease distribution similar to that in 2006, the number of issued PC in 2008 was decreased by 26.6% compared to that in 2006. In 2008, post-transfusion platelet counts, pre-transfusion platelet counts in patients transfused with 320 mL whole blood-derived PC, and platelet increments in patients transfused with 400 mL whole blood-derived PC were significantly decreased. However, the mean transfusion frequency per one month was not significantly different, 4.3 times in 2006 and 4.7 in 2008. CONCLUSIONS: By implementing a policy of platelet TD restriction, the amount of total issued PC was markedly decreased. Although post-transfusion platelet counts were decreased, the transfusion frequency in a month was not significantly increased. The restriction of platelet TD was helpful for increasing physicians' recognition of blood shortage while achieving similar transfusion effects. We conclude that 6 units of PC would be a better guideline for the platelet TD.