Fecal calprotectin as an index of intestinal inflammation

The assessment of inflammatory activity in intestinal disease in man can be done using a variety of different techniques, from measurement of conventional noninvasive acute-phase inflammatory markers in plasma (C-reactive protein and the erythrocyte sedimentation rate) to the direct assessment of disease activity by intestinal biopsy. However, most of these techniques have significant limitations when it comes to assessing functional components of the disease that relate to activity and prognosis. Here we briefly review the value of a novel emerging intestinal function test, fecal calprotectin. Single stool assay of neutrophil-specific proteins (calprotectin, lactoferrin) give the same quantitative data on intestinal inflammation as the 4-day fecal excretion of indium-111-labeled white cells. Elevated levels of fecal calprotectin have been demonstrated in patients with NSAID-induced enteropathy and have been used in the diagnosis of colorectal cancer. Fecal calprotectin is increased in over 95% of patients with inflammatory bowel disease (IBD) and correlates with clinical disease activity. It reliably differentiates between patients with IBD and irritable bowel syndrome (IBS). More importantly, at a given fecal calprotectin concentration in patients with quiescent IBD, the test has a specificity and sensitivity in excess of 85% in predicting clinical relapse of disease. This suggests that relapse of IBD is closely related to the degree of intestinal inflammation and suggests that targeted treatment at an asymptomatic stage of the disease may be indicated. (c) 2001 Prous Science. All rights reserved.