Normal fecal calprotectin level rules out likelihood of IBD

Investigators determined that the fecal calprotectin level of a child with suspected inflammatory bowel disease (IBD) could serve as a screening test to identify those with a high likelihood for IBD, reducing the number of children and teenagers who undergo endoscopy.

The study was performed in the pediatric outpatient clinics of 7 hospitals in the Netherlands in 117 youngsters aged between 6 and 18 years (mean age, 14 years) with abdominal complaints. All patients underwent measurement of fecal calprotectin.

Pediatricians, who were blinded to the results of these tests, referred for endoscopy 68 patients they highly suspected had IBD, based on global assessment, physical examination, and blood results. Forty-two patients (36% of all study participants) had confirmed IBD.

Most of the patients without IBD who had endoscopy did not need this test to exclude IBD and had other tests that led to their diagnoses, which included miscellaneous and nonorganic gastrointestinal diseases and infectious disease. If the pediatricians had referred only those patients with a positive fecal calprotectin result (>50 µg/g), 54 patients would have undergone endoscopy. Further, basing referral for endoscopy on a positive fecal calprotectin result in the absence of gastrointestinal infection would have resulted in no missed IBD cases (Van de Vijver E, et al. Arch Dis Child. 2012;97[12]:1014-1018).

Commentary

Wait for more information before requesting this calprotectin test: It was studied here in a highly selected referral population with a higher likelihood of IBD than most groups. That high prevalence of disease generated a higher positive predictive value for the test than would be seen in a lower-risk population. Nonetheless, further testing may show that this assay is a helpful screen when you are considering referral to GI for possible IBD. -Michael Burke, MD