Validation of a new extraction device for measuring faecal calprotectin in inflammatory bowel disease, and comparison to established extraction methods

Abstract

Objective: Faecal (f-) calprotectin is a widely used surrogate marker of intestinal inflammation. F-calprotectin analysis is labour demanding partly due to a time consuming extraction step. The aim of this project was to validate a new extraction method for f-calprotectin. Material and methods: A prospective multicentre study included 135 patients with an established diagnosis of inflammatory bowel disease. The patients submitted a faeces sample, which was extracted with both the conventional method at the participating laboratory and the new extraction device. The extracts were analyzed by an automated ELISA instrument. Results: Method comparison of the traditional method and the new device showed a slope of 1.01 (0.93–1.07) with intercept of − 2.2 (− 4.9–0.6). The Spearman rank correlation coefficient was 0.96. Conclusions: The new extraction device is a reliable and time saving alternative to the conventional extraction method.

Keywords::

• Biological markers
• colitis
• ulcerative
• Crohn disease
• enzyme-linked immunosorbent assay
• faeces
• inflammatory bowel disease
• leukocyte L1 antigen complex

Acknowledgements

The authors would like to thank the following persons for the collection of data: Tore Bjørn Grimstad, Stavanger University Hospital; Randi Opheim, Oslo University Hospital; Magne Henriksen, Østfold Hospital Trust; Roald Torp, Innlandet Hospital Hamar; Øistein Hovde, Innlandet Hospital Gjøvik; Tomm Bernklev, Telemark Hospital Trust; Jørgen Jahnsen, Akershus University Hospital; Ingrid Prytz Berset, Ålesund Hospital; and Svein Oskar Frigstad, Vestre Viken Hospital Bærum.

We would also like to thank Calpro AS for providing the ELISA kits and extraction devices used in this study.

VK participated in the design of the study, carried out the studies and data analyses and drafted the manuscript. TL carried out the samples analyses, performed the statistical analyses and participated in drafting the manuscript. LPJJ participated in the design of the study, and supervised inclusion of study participants and data collection. BM designed the study, participated in coordination and participated in drafting the manuscript. All authors revised the manuscript for intellectual content, and read and approved the final manuscript.

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.