Calprotectin is an abundant neutrophil protein found in both plasma and stool that is markedly elevated in infectious and inflammatory conditions, including inflammatory bowel disease (IBD). We conducted a systematic review of the published literature regarding fecal calprotectin to evaluate its potential as a noninvasive marker of neutrophilic intestinal inflammation. Reference ranges for fecal calprotectin have been established in healthy adults and children, and elevated concentrations of fecal calprotectin have been demonstrated in numerous studies of patients with IBD. Fecal calprotectin correlates well with histological inflammation as detected by colonoscopy with biopsies and has been shown successfully to predict relapses and detect pouchitis in patients with IBD. Fecal calprotectin has been shown to consistently differentiate IBD from irritable bowel syndrome because it has excellent negative predictive value in ruling out IBD in undiagnosed, symptomatic patients. Fecal calprotectin also may be useful in determining whether clinical symptoms in patients with known IBD are caused by disease flares or noninflammatory complications/underlying irritable bowel syndrome and in providing objective evidence of response to treatment. Although more studies are needed to define fully the role of fecal calprotectin, convincing studies and growing clinical experience point to an expanded role in the diagnosis and management of IBD.
1 From the Division of Gastroenterology, Hepatology, and Nutrition, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
*Reprints: Division of Gastroenterology, Hepatology, and Nutrition, Cincinnati Children's Hospital Medical Center, 3333 Burnet Ave, MLC 2010, Cincinnati, OH 45229
Received 31 October 2005; Accepted 13 March 2006