Performance Evaluation of the Afinion AS100 Analyzer for Its Use in the Albumin Creatinine Ratio Test

BACKGROUND: Early detection of moderately increased albuminuria using the albumin-creatinine ratio (ACR) test is very important for preventing renal insufficiency and cardiovascular disease in patients with diabetes. The purpose of this study was to analyse the clinical usefulness of the Afinion AS100 Analyzer (Alere Technologies AS, Norway) for determining the ACR by evaluating its precision and linearity and comparing it with another conventional device. METHODS: Urine samples of patients and quality control materials were used for evaluation. The Afinion AS100 was used to measure albumin and creatinine, and the ACR was automatically calculated. The Cobas Integra 800 (Roche Diagnostics, Germany) was used as a reference instrument for correlation analysis. In accordance with the Clinical and Laboratory Standards Institute guidelines, precision, linearity, and turnaround time were evaluated, and the Afinion AS100 was compared with another device. RESULTS: The total coefficients of variation of albumin and creatinine were 2.8% and 2.9% for high concentration and 2.9% and 2.5% for low concentration, respectively. Both albumin and creatinine showed coefficients of determination of 0.999 or higher in linearity. Correlation coefficients of albumin, creatinine, and ACR were higher than the Clinical and Laboratory Standards Institute recommended value of 0.975, suggesting a high correlation as well as showing significant correlation with a 24-hour urinary albumin level obtained using the Cobas Integra 800. Mean turnaround time was 5 minute 35 seconds. CONCLUSIONS: The albumin, creatinine, and ACR tests performed with the Afinion AS100 showed satisfactory performance in terms of precision and linearity and showed good correlation with the central laboratory instrument and a 24-hour urine albumin quantitative test using a conventional instrument.

Comparison of HbA(1c) Analyzers: D-10, Variant II Turbo, Cobas Integra 800, and Afinion AS100 / 대한진단검사의학회지

BACKGROUND: The purpose of this study was to evaluate the performance and agreement among HbA(1c) values measured using selected analyzers certified by the National Glycohemoglobin Standardization Program (NGSP) and standardized by the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC). METHODS: HbA(1c) determined using D-10 (Bio-Rad, USA), Variant II Turbo (Turbo; Bio-Rad, USA), Cobas Integra 800 (Integra; Roche, Switzerland) and Afinion AS100 (Afinion; Axis-Shield, Norway) were compared with each other. Precision and method comparisons with Deming regression were evaluated according to CLSI recommendations. We also compared the HbA(1c) values obtained with each analyzer using either IFCC or NGSP methods by correlation analysis and kappa statistics. RESULTS: The repeatability and method/device precisions of D-10 and Afinion were acceptable. The correlation coefficients of HbA(1c) were 0.986 for D-10 vs. Afinion, 0.997 for D-10 vs. Turbo, 0.988 for D-10 vs. Integra, and 0.991 for Integra vs. Afinion. The average biases of HbA(1c) Afinion (IFCC) and HbA(1c) Integra (IFCC) against HbA(1c) D-10 (NGSP) were -1.90% and -1.79%, respectively. Kappa agreement statistics for the three diabetic control group HbA(1c) values of "less than 6.5%," "6.5%-7.5%," and "greater than 7.5%" for D-10 vs. Turbo, D-10 vs. Integra, and D-10 vs. Afinion were 0.872, 0.836, and 0.833, respectively. CONCLUSIONS: The strong correlations and good clinical agreements of HbA(1c) between each analyzer expressed in terms of either NGSP or IFCC-derived NGSP indicate that these analyzers can be used interchangeably.