Lab Med Online.  2019 Jan;9(1):1-5. 10.3343/lmo.2019.9.1.1.

Analytical Performance of INNOVANCE Free Protein S Antigen on Sysmex CS-5100

• Park S
• Park S
• Lee J
• Huh J

• KMID: 2430202
• DOI: http://doi.org/10.3343/lmo.2019.9.1.1

Abstract

BACKGROUND
Protein S deficiency is a common cause of thrombophilia. Free protein S has been suggested as one of the best screening tests for this deficiency. We evaluated an immunoturbidimetric free protein S reagent, INNOVANCE Free Protein S Antigen (Free PS Ag; Siemens Healthcare Diagnostics, Germany), using a CS-5100 coagulation analyzer (Sysmex, Japan).
METHODS
The performance of INNOVANCE Free PS Ag was evaluated according to the CLSI guidelines. Precision, linearity, and verification of reference intervals were examined. The INNOVANCE Free PS Ag was also compared by the STA-Liatest Free Protein S immunoturbidimetric assay (Diagnostica Stago, France).
RESULTS
The repeatability and within-laboratory imprecision of INNOVANCE Free PS Ag were 0.8% CV and 2.0% CV at the normal level, and 1.3% CV and 2.3% CV at the abnormally low level, respectively. This assay showed linearity from 4.0% to 151.9% (correlation coefficient r=1, P < 0.0001). Reference intervals for males and females were verified as acceptable. INNOVANCE Free PS Ag was comparable with STA-Liatest Free Protein S with a very high correlation (r=0.935, P < 0.0001). The results for the INNOVANCE antigen were higher.
CONCLUSIONS
The INNOVANCE Free PS Ag on a Sysmex CS-5100 coagulation analyzer has excellent analytical performance and is comparable with the STA-Liatest Free Protein S assay.

Keyword

Protein S; Immunoturbidimetry; Performance

MeSH Terms

Delivery of Health Care
Female
Humans
Male
Mass Screening
Protein S Deficiency
Protein S*
Thrombophilia
Protein S

Figure

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  Fig. 1 Linearity of INNOVANCE Free Protein S Antigen on Sysmex CS-5100.

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  Fig. 2 Comparison of free protein S between INNOVANCE Free Protein S Antigen on Sysmex CS-5100 and STA-Liatest Free Protein S on STA-R Max. (A) Comparison with Deming regression. (B) Difference plot.

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