Exploratory study on reference intervals of calprotectin and pentraxin 3

Area of Science:

• Clinical Chemistry
• Biomarker Discovery
• Laboratory Medicine

Background:

• Accurate reference intervals are crucial for interpreting biomarker levels in clinical diagnostics.
• Pentraxin 3 and calprotectin are emerging biomarkers for inflammatory conditions.
• Standardized methods are needed for reliable biomarker quantification.

Purpose of the Study:

• To establish reference intervals for serum pentraxin 3 and serum/urine calprotectin.
• To adhere to CLSI EP28-A3C guidelines for reference interval determination.
• To provide method-specific reference values for clinical laboratory use.

Main Methods:

• Utilized 120 serum and urine samples from healthy volunteers/outpatients.
• Employed a turbidimetric method for calprotectin and ELISA for pentraxin 3.
• Ensured participants had normal CRP, leukocyte counts, renal function, and no history of inflammatory diseases or cancer.

Main Results:

• Established serum calprotectin reference range: ≤3.6 mg/L (90% CI: 3.1-4.1 mg/L).
• Established serum pentraxin 3 reference range: ≤3.0 µg/L (90% CI: 2.7-3.2 µg/L).
• Established urine calprotectin reference range: ≤1.4 mg/L (90% CI: 1.0-1.7 mg/L).

Conclusions:

• Reported sample and method-specific reference intervals for serum pentraxin 3 and calprotectin.
• These intervals support the detection and monitoring of inflammatory conditions.
• The findings contribute to standardized biomarker interpretation in clinical practice.