A novel turbidimetric immunoassay for fecal calprotectin optimized for routine chemistry analyzers

J Clin Lab Anal. 2017 Jul;31(4):e22061. doi: 10.1002/jcla.22061. Epub 2016 Sep 15.

Abstract

Background: Fecal calprotectin assays are widely used to exclude inflammatory bowel disease (IBD) in patients with suspected IBD. A problem with the fecal calprotectin assays is the rather long test-turnaround times. A particle enhanced turbidimetric immunoassays (PETIA) for fecal calprotectin would reduce test-turnaround times and would permit more laboratories to perform the measurements. The aim of this study was to evaluate a new feces calprotectin PETIA.

Method: Using routine fecal samples the feces calprotectin PETIA was validated on two chemistry analyzers, Mindray BS-380 and Cobas 501.

Results: The assay is linear in the range 11-2000 μg/g, with a limit of quantitation of approximately 10 μg/g. No antigen excess hook effect was observed up to 10 000-15 000 μg/g depending on the instrument used. The turbidimetric method showed a good agreement with the Bühlmann ELISA. The total coefficient of variation was 3%-8% in the 50-100 μg/g range.

Conclusion: The fecal calprotectin PETIA, fCal Turbo, is well suited for rapid analysis of fecal calprotectin on Mindray BS-380 or Cobas 501 clinical chemistry analyzers. The test results are commutable with Bühlmann fecal MRP8/14 ELISA.

Keywords: biological markers; calprotectin; feces; humans; inflammatory bowel diseases; method validation.

MeSH terms

  • Biomarkers / analysis*
  • Feces / chemistry*
  • Humans
  • Immunoturbidimetry / methods*
  • Inflammatory Bowel Diseases / diagnosis
  • Leukocyte L1 Antigen Complex / chemistry*
  • Limit of Detection
  • Linear Models
  • Reproducibility of Results

Substances

  • Biomarkers
  • Leukocyte L1 Antigen Complex