Vendel Kristensen1,2, Gunn Helen Malmstrøm1, Viggo Skar1, Arne Røseth3, Bjørn Moum2,4. 1. a Department of Medicine , Unger-Vetlesen's Institute, Lovisenberg Diaconal Hospital , Oslo , Norway ; 2. b Institute of Clinical Medicine , University of Oslo , Oslo , Norway ; 3. c Department of Medicine, Section of Gastroenterology , Lovisenberg Diaconal Hospital , Oslo , Norway ; 4. d Department of Gastroenterology , Oslo University Hospital , Oslo , Norway.
Abstract
OBJECTIVE: Faecal (f-) calprotectin is a biomarker of intestinal inflammation. Previous studies have described intra-individual day-to-day variability of this biomarker in patients with inflammatory bowel disease (IBD) and morning samples have been suggested for standardisation purposes. With this project, we investigated if day-to-day variability differed from diurnal variability. Additionally, we evaluated a new extraction method for f-calprotectin analysis. METHODS: Fifty patients provided three faeces samples from morning - evening - morning on two consecutive days. Nineteen patients provided two faeces samples from the same bowel movement, one conventional spot sample, and one sample with a device for patient-administered sampling and extraction. RESULTS: The two morning samples differentiated between mucosal inflammation and mucosal healing with same level of agreement as the two samples from the same day (kappa 0.76), using an f-calprotectin cut-off level of 259 μg/g. Although large intra-individual variation in f-calprotectin values, there were no significant day-to-day (p = 0.096) or diurnal variation (p = 0.78). Used by laboratory technicians, the new extraction device correlated significantly with the conventional extraction method (p < 0.001), Spearman's rank correlation coefficient 0.95. Of the 19 patients testing patient administered extraction, two patients provided samples leading to considerably higher f-calprotectin levels than conventional sampling procedure. CONCLUSIONS: The reliability of f-calprotectin morning samples is equal to the reliability of samples from different bowel movements on the same day. The new extraction method is reliable when used by laboratory technicians, but larger studies are recommended to evaluate patient administered extraction.
OBJECTIVE: Faecal (f-) calprotectin is a biomarker of intestinal inflammation. Previous studies have described intra-individual day-to-day variability of this biomarker in patients with inflammatory bowel disease (IBD) and morning samples have been suggested for standardisation purposes. With this project, we investigated if day-to-day variability differed from diurnal variability. Additionally, we evaluated a new extraction method for f-calprotectin analysis. METHODS: Fifty patients provided three faeces samples from morning - evening - morning on two consecutive days. Nineteen patients provided two faeces samples from the same bowel movement, one conventional spot sample, and one sample with a device for patient-administered sampling and extraction. RESULTS: The two morning samples differentiated between mucosal inflammation and mucosal healing with same level of agreement as the two samples from the same day (kappa 0.76), using an f-calprotectin cut-off level of 259 μg/g. Although large intra-individual variation in f-calprotectin values, there were no significant day-to-day (p = 0.096) or diurnal variation (p = 0.78). Used by laboratory technicians, the new extraction device correlated significantly with the conventional extraction method (p < 0.001), Spearman's rank correlation coefficient 0.95. Of the 19 patients testing patient administered extraction, two patients provided samples leading to considerably higher f-calprotectin levels than conventional sampling procedure. CONCLUSIONS: The reliability of f-calprotectin morning samples is equal to the reliability of samples from different bowel movements on the same day. The new extraction method is reliable when used by laboratory technicians, but larger studies are recommended to evaluate patient administered extraction.
Authors: Ferdinando D'Amico; David T Rubin; Paulo Gustavo Kotze; Fernando Magro; Britta Siegmund; Taku Kobayashi; Pablo A Olivera; Peter Bossuyt; Lieven Pouillon; Edouard Louis; Eugeni Domènech; Subrata Ghosh; Silvio Danese; Laurent Peyrin-Biroulet Journal: United European Gastroenterol J Date: 2021-05-07 Impact factor: 4.623
Authors: R Gacesa; A Vich Vila; V Collij; Z Mujagic; A Kurilshikov; M D Voskuil; E A M Festen; C Wijmenga; D M A E Jonkers; G Dijkstra; J Fu; A Zhernakova; F Imhann; R K Weersma Journal: Gut Microbes Date: 2021 Jan-Dec