Performance Evaluation of HbA1c Test on the Toshiba 200FR NEO Using AutoLab HbA1c Reagent / 임상검사와정도관리

BACKGROUND: Hemoglobin A1c (HbA1c) is widely used for the monitoring of glycemic control in diabetes mellitus patients. Various methods are applied for the determination of HbA1c levels. Recently, a novel National Glycohemoglobin Standardization Program (NGSP)-certificated reagent (AutoLab HbA1c, IVD-LAB, Korea) was introduced for use in an automated chemistry analyzer. We evaluated the analytical performance of this immunoturbidimetry reagent and compared it with the ion-exchange high performance liquid chromatography (Variant II Turbo, Bio-Rad Laboratories, Inc., USA) and immunoassay (Cobas Integra 800, Roche Diagnostics, Germany) methods. METHODS: Toshiba 200FR NEO (Toshiba Medical Systems Co., Japan) with the AutoLab reagent was evaluated for precision, linearity, carryover and compared with Cobas Integra and Variant II Turbo. RESULTS: Coefficients of variation (CVs) of within-run imprecision for low and high level were 1.8% and 0.7%, respectively. CVs of within-laboratory imprecision for low and high level were 2.4% and 1.0%, respectively. The linearity was excellent with R2 = 0.99 in the range of 3.05-15.50%. It was well correlated with Variant II Turbo (R=0.9904) and Cobas Integra 800 (R=0.9992). The carryover rate was 0.4%. CONCLUSIONS: The Toshiba 200FR NEO with the AutoLab reagent showed excellent precision and linearity and minimal carryover rate. It was well correlated with the other widely used methodological instruments. It may be used for the diagnosis and the treatment monitoring of diabetes.

Laboratory Evaluation of Bone Metabolism Index Using Elecsys 2010 / 대한진단검사의학회지

BACKGROUND: Bone markers can provide a prognostic information about the risk of osteoporotic fracture and are useful tools for monitoring the efficacy of antiresorptive therapy. We evaluated the analytical performance of the bone markers of Elecsys 2010 (Roche Diagnostics Corp., Indianapolis, USA). METHODS: We evaluated the analytical performance of the Elecsys 2010 for serum parathyroid hormone (PTH), osteocalcin, and serum bone-derived degradation products of type I collagen C-telopeptide (S-CTX) using control material and patients' specimens. For the comparison studies, an immunoradiometric assay was used for PTH and an ELISA for serum osteocalcin and serum bone-derived degradation products of type I collagen N-telopeptide (S-NTX). We established the reference intervals of S-CTX and serum osteocalcin by analyzing 4569 Korean healthy subjects according to sex and age. RESULTS: Within-run and total CV of most items were below 5% except S-CTX low level (5.42%). Elecsys 2010 showed a good linearity (r> or =0.99, P<0.01). Good correlations with other methods were found in osteolcalcin (r=0.95, P<0.01) and PTH (r=0.96, P<0.01). S-CTX showed a good correlation with S-NTX (r=0.76, P<0.01). Reference intervals of serum osteocalcin (ng/mL) and S-CTX (ng/mL) were 9.58-33.62 and 0.18-0.89, respectively, in adult male, 8.00-31.46 and 0.11-0.81 in 31-50 years old female, and 8.30-43.50 and 0.11-1.00 in 51-80 years old female. CONCLUSIONS: Elecsys 2010 bone markers showed a satisfactory precision, linearity, and a good correlation with other methods. With its 'one system-many capabilities' features, Elecsys 2010 would be a useful tool for measuring bone metabolism indices.

Evaluation of Dimension(R) RxL Automated Chemistry Analyzer / 임상검사와정도관리

BACKGROUND: The Dimension(R) RxL (Dade Behring Inc., Illinois) is a newly developed, high-throughput and versatile automated chemistry analyzer with continuous and random-access features for routine chemistry tests, enzymes, electrolytes, therapeutic drug monitoring, cardiac markers, and hormones. We evaluated the usefulness of Dimension(R) RxL in the aspect of precision, linearity, and comparison. METHODS: We evaluated the analytical performance of the Dimension(R) RxL for aspartate aminotransferase, alanine aminotransferase, high density lipoprotein cholesterol, blood urea nitrogen, creatinine, glucose, total bilirubin, total iron binding capacity, sodium, potassium, chloride, total CO2, digoxin, phenytoin, valporic acid, CK-MB, myoglobin and cardiac troponin-I. We used control materials for linearity and precision evaluation and random patients sera for comparison study with Hitachi 747 (Hitachi LTD., Tokyo, Japan), TDxFLx(TM) (Abbott Diagnotistics, Chicago) and ACS: Centaur(TM) (Bayer Diagnotistics, New York) according to NCCLS guidelines. RESULTS: In the precision study, within-run and total CVs of most items were below 5% except CK-MB and cardiac troponin-I. The linearities were maintained well in the range of medically significant levels and were statistically acceptable (P<0.001). The comparison study indicated good correlation with the central laboratory analyzer and correlation coefficients were above 0.975 (P<0.01). CONCLUSIONS: Dimension(R) RxL showed satisfactory precision, linearity, and good correlation compared with other analyzers. Because it has features of one system with many capabilities, we recommend that Dimension(R) RxL would be used for the routine chemistry setting or stat test settings at medium- to large-sized hospitals.