Ma C^1,2, Battat R^2,3, Parker CE², Khanna R⁴, Jairath V^2,4,5, Feagan BG^2,4,5. Expert Rev Gastroenterol Hepatol. 2019 Apr;13(4):319-330. doi: 10.1080/17474124.2019.1563481. Epub 2019 Jan 3.

Author information

1 a Division of Gastroenterology and Hepatology , University of Calgary , Calgary , Alberta , Canada.

2 b Robarts Clinical Trials Inc ., London , Ontario , Canada.

3 c Division of Gastroenterology , University of California San Diego , La Jolla , CA , USA.

4 d Department of Medicine , Western University , London , Ontario , Canada.

5 e Department of Epidemiology and Biostatistics , Western University , London , Ontario , Canada.

Abstract

'Treat-to-target' paradigms in Crohn's disease (CD) directed at suppressing intestinal inflammation require accurate and reliable measures of disease activity. Although endoscopy has traditionally been considered a gold standard, cost, complexity, resource limitations, and invasiveness are important limitations. Hence, substantial interest exists for non-invasive serum and fecal biomarkers, namely C-reactive protein (CRP) and fecal calprotectin (FC), in the diagnosis, monitoring, and treatment of CD. Areas covered: We review the evidence for using serum CRP and FC in distinguishing patients with CD from those with irritable bowel syndrome, categorizing disease activity among patients with an established diagnosis of CD, predicting the likelihood of treatment response, identifying asymptomatic patients in medically or surgically induced remission who are at risk for disease relapse, and as treatment targets. Expert commentary: Accurate interpretation of CRP and FC is dependent on several factors including the clinical context, the performance characteristics of the assay, the specified test cut-offs, and the pre-test probability of disease. Emerging evidence indicates that CRP and FC are valuable adjuncts for the management of CD in specific circumstances described in this review.