Fecal immunochemical test predicts mucosal healing in ulcerative colitis

Last Updated: 2015-04-10

By Will Boggs MD

NEW YORK (Reuters Health) - A quantitative fecal immunochemical test (FIT) predicts mucosal healing in ulcerative colitis at least as well as the more expensive fecal calprotectin (Fcal), researchers from Japan report.

"Although Western physicians stick to Fcal, FIT, whose availability is largely growing due to prevalence of colorectal cancer screening in their countries, is recommended as a low-cost substitute of Fcal," Dr. Sakiko Hiraoka from Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences told Reuters Health by email.

Beyond clinical remission, mucosal healing is another treatment goal in ulcerative colitis, but its definitive evaluation requires colonoscopic examination. FIT and Fcal are promising surrogate markers that have been shown to predict the presence of active inflammation in these patients.

Dr. Hiraoka and colleagues prospectively examined simultaneous Fcal and FIT using stool samples from 92 ulcerative colitis patients who underwent colonoscopy and compared their ability to predict mucosal healing.

They defined clinical remission as a Mayo stool frequency subscore of 0 or 1 and a Mayo rectal bleeding subscore of 0; mucosal healing was defined as a Mayo endoscopic subscore (MES) of 0, or 0 or 1 throughout the colorectum.

The FIT and Fcal results correlated significantly with the maximum MES, the total inflammation score, the Geboes histological score, and with each other, the researchers report in The American Journal of Gastroenterology, online March 31.

FIT and Fcal performed similarly when mucosal healing was defined as an MES of 0 or 1. For complete mucosal healing (an MES of 0), however, the sensitivity and specificity of an FIT value below 100 ng/ml were 0.95 and 0.62, respectively, whereas those of an Fcal value below 250 mcg/g were 0.82 and 0.62.

The cost of one-time FIT is around $22, the researchers note, compared with around $180 for one Fcal measurement.

"FIT can be measured approximately 10 times at the cost of one-time Fcal," Dr. Hiraoka said. "Closely measurable FIT enables inflammatory bowel disease physicians to survey the clinical status of ulcerative colitis more meticulously."

"Fcal may be superior in cases with proximal colon-dominant inflammation, because the sensitivity of FIT for proximal neoplasia has been shown (to be) lower," Dr. Hiraoka said. "However, such cases are relatively rare in ulcerative colitis."

Whether FIT accurately predicts clinical relapse is under investigation, Dr. Hiraoka added.

SOURCE: http://bit.ly/1FtWhMF

Am J Gastroenterol 2015.