Guideline newly recommends biomarkers to monitor Crohn's disease

A new guideline from the American Gastroenterological Association (AGA) recommends using blood- and stool-based biomarkers to help manage Crohn's disease.

To develop the guideline, the first of its kind, a multidisciplinary panel reviewed evidence on the use of biomarkers in patients with established Crohn's disease who were asymptomatic, had symptoms of varying severity, or were in surgically induced remission. Biomarker performance was assessed against the gold standard of endoscopic activity, which was defined as a Simple Endoscopic Score for Crohn's Disease of three or greater.

For patients with Crohn's disease who are in symptomatic remission, the guideline suggests using both biomarkers and symptoms to monitor disease activity, with C-reactive protein (CRP) and fecal calprotectin (FCP) checked every six to 12 months, noting that the tests will work best if levels have previously matched disease activity seen on endoscopy. Endoscopic evaluation can be avoided in those with an FCP level less than 150 μg/g and/or a CRP level below 5 mg/L, the guideline said, but added that “elevated biomarkers in this setting merit confirmation with endoscopy before treatment adjustment.”

In patients with Crohn's disease who are being treated for mild symptoms, CRP and FCP levels can be checked and treatment adjusted every two to four months, the guideline said. After symptoms resolve and biomarkers normalize, endoscopic and/or radiologic evaluation should be done, typically six to 12 months after treatment initiation or adjustment, to rule out active inflammation, according to the guideline. In patients whose symptoms are moderate to severe, the AGA suggests using FCP to rule in active inflammation and inform treatment adjustment and avoid routine endoscopy. In those with moderate to severe symptoms and normal FCP and CRP levels, the AGA suggests endoscopic assessment of disease activity rather than empiric treatment adjustment.

In asymptomatic patients with Crohn's disease who are in surgically induced remission within the past 12 months, are at low risk for postoperative recurrence, or have at least one risk factor for recurrence but are taking postoperative pharmacologic prophylaxis, the guideline suggests using an FCP level of 50 μg/g or lower to avoid routine endoscopy. Endoscopy is suggested in asymptomatic patients with surgically induced remission within the past 12 months who are at high baseline risk for recurrence and are not receiving postoperative pharmacologic prophylaxis.

The guideline was published Nov. 17 by Gastroenterology, along with a clinical decision support tool and an infographic.