Endoscopic Factors Influencing Fecal Calprotectin Value in Crohn's Disease.
OBJECTIVE
Fecal calprotectin [fcal] is a biomarker of Crohn's disease [CD] endoscopic activity. Identifying the endoscopic situations in which fcal is less reliable remains unexplored. We aimed to determine the endoscopic factors influencing fcal level in CD.


METHODS
Overall, 53 CD patients consecutively and prospectively underwent colonoscopy, with CD Endoscopic Index of Severity [CDEIS] calculation and stool collection. Fcal was measured using a quantitative immunochromatographic test. Correlation analysis was done with Pearson statistics.


RESULTS
Fcal was correlated with CDEIS [0.66, p < 0.001]. In univariate analysis, fcal was correlated with the affected surface [0.65, p < 0.001] and the ulcerated surface [0.47, p < 0.001]. Fcal was significantly associated with ulceration depth, with median fcal of 867.5 µg/g, 1251.0 µg/g, and 1800.0 µg/g, in patients presenting with non-ulcerated lesions, superficial ulcerations [SU], and deep ulcerations [DU], respectively. Lesion locations did not influence fcal. In multivariate analysis, fcal was associated with affected surface [p = 0.04] and the presence of CD lesions. Moreover, fcal increased with the ulceration depth [p = 0.03]. However, ulcerated surface and CD location did not affect fcal. Using a receiver operating characteristic [ROC] curve, we showed that fcal of 400 µg/g was the best compromise between sensitivity [0.76] and specificity [0.77], whereas fcal ≥ 200 µg/g was highly sensitive [0.86] to detect SU or DU.


CONCLUSIONS
Fcal is a very reliable biomarker to detect endoscopic ulcerations in CD. We suggest repeating measurement in case of intermediary results [200-400 µg/g] in daily practice. Fcal level is mostly influenced by the presence of CD lesions [even non-ulcerated], in a depth-related manner and by the affected surface.
University Hospital Estaing, Gastroenterology Department, Clermont-Ferrand, France.
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Goutorbe
University Hospital Estaing, Gastroenterology Department, Clermont-Ferrand, France UMR 1071 Inserm/Universite d'Auvergne; USC-INRA 2018, Clermont-Ferrand, France.
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Goutte
GM Clermont-Ferrand University and Medical Center, Biochemistry Unit, Clermont- Ferrand, France.
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Minet-Quinard
University Hospital Estaing, Gastroenterology Department, Clermont-Ferrand, France.
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Boucher
GM Clermont-Ferrand University and Medical Center, DRCI, Biostatistics Unit, Clermont-Ferrand, France.
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Pereira
University Hospital Estaing, Gastroenterology Department, Clermont-Ferrand, France UMR 1071 Inserm/Universite d'Auvergne; USC-INRA 2018, Clermont-Ferrand, France.
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Bommelaer
University Hospital Estaing, Gastroenterology Department, Clermont-Ferrand, France UMR 1071 Inserm/Universite d'Auvergne; USC-INRA 2018, Clermont-Ferrand, France a_buisson@chu-clermontferrand.fr.
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A
Buisson
D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000378:metabolism; D003113:Colonoscopy; D003424:Crohn Disease / Q000175:diagnosis* / Q000378:metabolism; D005243:Feces / Q000737:chemistry*; D005260:Female; D006801:Humans; D039841:Leukocyte L1 Antigen Complex / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011446:Prospective Studies; D012372:ROC Curve; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D016037:Single-Blind Method
D015415:Biomarkers; D039841:Leukocyte L1 Antigen Complex
Crohn’ s disease; Crohn’s Disease Endoscopic Index of Severity; biomarker; endoscopy; fecal calprotectin