New Screening Test for IBD

July 16, 2010

Screening for fecal calprotectin may reduce the number of endoscopic procedures performed while evaluating patients for IBD.

Researchers from the University Medical Center Groningen in the Netherlands recently published a study in the British Medical Journal that reviews whether or not fecal calprotectin is an effective test for reducing the number of endoscopic procedures performed during the investigation of suspected inflammatory bowel disease (IBD).

The researchers used data from studies found in Medline and Embase up until October 2009, evaluating the measurement of fecal calprotectin level (index test) compared with endoscopy and histopathology of segmental biopsy samples (reference standard). Among the 13 studies the researchers evaluated — six of which were in adults, seven in children — "the pooled sensitivity and pooled specificity of calprotectin was 0.93 (95% confidence interval 0.85 to 0.97) and 0.96 (0.79 to 0.99)" in the studies of adults, and "0.92 (0.84 to 0.96) and 0.76 (0.62 to 0.86)" in children and teenagers. According to the researchers, measuring fecal calprotectin levels would reduce the number of adults requiring endoscopy by 67%.

The researchers did note several factors to consider when reviewing the study results. Three of the 33 adults who participated in the study “will not have inflammatory bowel disease, but may have a different condition for which endoscopy is inevitable,” according to the team. Additionally, “in the population of children and teenagers, 65 instead of 100 would undergo endoscopy. Nine of them will not have inflammatory bowel disease, and diagnosis will be delayed in 8% of the affected children.” The team also notes that the downside of this screening strategy “is delayed diagnosis in 6% of adults because of a false negative test result.”

Overall, however, the researchers believe that testing for fecal calprotectin could one day have positive implications when screening patients for IBD.

"If studies conducted in primary care find a high diagnostic accuracy of the fecal calprotectin test it will be an important step forward in how inflammatory bowel disease is diagnosed," wrote Robert Logan, consultant gastroenterologist at Kings College Hospital in London, in an accompanying editorial.