Fecal calprotectin predicts bowel inflammation in patients with rheumatological disorders

Last Updated: 2020-01-02

By Reuters Staff

NEW YORK (Reuters Health) - Elevated fecal calprotectin levels predict bowel inflammation in patients with ankylosing spondylitis (AS) or spondyloarthritis (SpA), according to a systematic review.

Gut inflammation is common in patients with AS and SpA, and as many as 14% of patients with these diseases develop inflammatory bowel disease (IBD) during their lifetime.

Fecal calprotectin levels are correlated with clinical, endoscopic, and histological measures of disease activity in patients with IBD, and some studies have suggested that they might also predict the onset of IBD in patients with AS and SpA.

Dr. Marine Fauny of the University Hospital of Nancy, in France, and colleagues evaluated the association between fecal calprotectin levels and bowel inflammation, including IBD, in patients with AS or SpA in their review of seven studies that included 238 patients with spondyloarthritis, 453 with ankylosing spondylitis, and 184 controls.

Overall, 21.2% to 70.7% of patients with SpA or AS had elevated fecal calprotectin levels, 11% to 80% had high fecal calprotectin levels and evidence of macroscopic mucosal changes; 41.7% to 100% of the patients with high fecal calprotectin levels had microscopic mucosal alterations.

In five studies, however, there was no correlation between fecal calprotectin values and gastrointestinal symptoms, the researchers report in the Journal of Crohn's and Colitis.

In one study, a fecal calprotectin level of 266 mg/kg at baseline predicted the development of Crohn's disease with 91.3% accuracy. In another, a fecal calprotectin level of 132 ug/g predicted small-bowel Crohn's disease with 75% accuracy.

Two other studies concluded that fecal calprotectin values could also detect the presence of intestinal inflammation.

Several studies found significant positive correlations between fecal calprotectin and C-reactive protein (CRP) levels. But otherwise correlations between fecal calprotectin levels and markers of disease activity were inconsistent.

Similarly, some studies found increases in fecal calprotectin levels among patients treated with NSAIDs and decreases in fecal calprotectin levels among patients treated with TNF-alpha inhibitors, whereas others found no such correlations.

"Fecal calprotectin measurement may allow the screening of high-risk patients in which endoscopic examination is needed for IBD diagnosis," the authors conclude. "This strategy could reduce the number of colonoscopies and positively impact on patient's burden."

"Further larger studies are necessary to define a globally accepted fecal calprotectin cut-off value in order to predict the onset of IBD in patients with spondylarthritis or ankylosing spondylitis," they add.

Dr. Fauny did not respond to a request for comments.

SOURCE: https://bit.ly/2SKYh4L Journal of Crohn's and Colitis, online December 20, 2019.