First certified reference material for cystatin C in human serum ERM-DA471/IFCC

Area of Science:

• Clinical Chemistry
• Biochemistry
• Reference Materials

Background:

• Accurate measurement of Cystatin C is crucial for assessing kidney function.
• Standardization of Cystatin C assays is needed to ensure reliable results across different laboratories.
• The International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) Working Group for the Standardisation of Cystatin C (WG-SCC) addresses this need.

Purpose of the Study:

• To announce the availability of a new certified reference material for Cystatin C (ERM-DA471/IFCC).
• To provide a standardized material for the accurate quantification of Cystatin C.
• To support the harmonization of Cystatin C measurements in clinical laboratories.

Main Methods:

• Development and characterization of a pure protein primary reference preparation (PRP) from recombinant Cystatin C.
• Determination of PRP concentration using dry mass measurement.
• Characterization of the certified reference material ERM-DA471/IFCC using particle enhanced immuno-nephelometry, particle enhanced immuno-turbidimetry, and enzyme amplified single radial immuno-diffusion.

Main Results:

• The certified Cystatin C mass concentration in ERM-DA471/IFCC is 5.48 mg/L.
• The expanded uncertainty (k=2) for the certified value is 0.15 mg/L.
• The material was characterized using a primary reference preparation calibrated by dry mass determination.

Conclusions:

• The new certified reference material ERM-DA471/IFCC provides a reliable standard for Cystatin C measurement.
• This material will aid in the standardization and harmonization of Cystatin C assays.
• Availability of ERM-DA471/IFCC supports improved clinical assessment of kidney function through accurate Cystatin C quantification.