J Lab Med Qual Assur.  2013 Dec;35(2):81-86.

Performance Evaluation of Gentian Cystatin C on the Hitachi 7600 Automatic Analyzer

• Jo YA
• Shin MK
• Song W
• Kim HS
• Park MJ

Abstract

BACKGROUND
Cystatin C, a 13-kDa protein synthesized in all nucleated cells, has been proposed as a replacement for serum creatinine in assessments of renal function. The Gentian Cystatin C immunoassay (Gentian, Norway) was recently developed using particle enhanced turbidimetric immunoassay. In this study, we evaluated the analytical performance of the Gentian Cystatin C immunoassay on the Hitachi 7600 Automatic Analyzer (Hitachi Ltd., Japan).
METHODS
We performed precision and linearity studies using Hitachi Clinical Analyzer 7600 with Gentian reagent and compared the results to those obtained with the N Latex Cystatin C (Siemens, Germany) using a particle enhanced nephelometric immunoassay method performed on the Behring Nephelometer II (Siemens, Germany). We also analyzed the traceability of Gentian reagent and Siemens reagent to Cystatin C standard reference material, ERM-DA471/IFCC.
RESULTS
The coefficient of variations (CVs) for within-run imprecision at low and high levels were 1.58% and 1.06% and the CVs for total imprecision at low and high levels were 2.53% and 2.09%, respectively. In the linearity test, the coefficient of determination (R2) was 0.9997 (range, 0.23 to 7.50 mg/L), and comparison with the results obtained by Siemens reagent showed an excellent correlation coefficient of 0.9982. In the traceability test, Gentian reagent is more accurate than Siemens reagent and the total accuracy was 96.0%.
CONCLUSIONS
Gentian reagent provides good analytic performance on the Hitachi 7600 Automatic Analyzer and can be used for the diagnosis, treatment, monitoring, and risk assessment of renal function.

Keyword

Cystatin C; Creatinine; Traceability

MeSH Terms

Creatinine
Cystatin C*
Diagnosis
Gentiana*
Immunoassay
Latex
Methods
Risk Assessment
Creatinine
Cystatin C
Latex