Measurement of fecal calprotectin effectively monitored recurrence of Crohn’s disease after intestinal resection, according to recent study data.
To determine whether fecal calprotectin, C-reactive protein or the Crohn’s disease activity index (CDAI) can accurately reflect the presence and severity of recurrent CD and predict future recurrence after intestinal resection, researchers analyzed data prospectively collected from 135 patients (44% men; median age, 36 years) who participated in a randomized controlled trial (POCER study) performed at multiple centers in Australia and New Zealand. This trial aimed to evaluate postoperative endoscopic assessment and treatment step-up for early mucosal recurrence. The protocol involved measurements of fecal calprotectin, C-reactive protein and CDAI at several points throughout the study period, and ileocolonoscopies were performed 6 and 18 months after surgery.
Among 319 stool samples tested, the median fecal calprotectin level decreased from 1,402 µg/g before surgery to 166 µg/g at 6 months after surgery, but was higher in patients with endoscopically confirmed disease recurrence compared with those in remission (275 µg/g vs. 72 µg/g; P < .001). When 6- and 18-month fecal calprotectin levels were combined they correlated with presence (r = 0.42; P < .001) and severity (r = 0.44; P < .001) of recurrence, whereas C-reactive protein and CDAI score did not. Fecal calprotectin concentrations greater than 100 µg/g indicated recurrence with 89% sensitivity, 58% specificity, 53% positive predictive value, 91% negative predictive value and 0.763 area underneath the receiver operator characteristic curve. Fecal calprotectin levels less than 51 µg/g in patients in remission at 6 months after surgery predicted maintenance of remission with 79% negative predictive value. Patients with recurrence at 6 months who had treatment step-up had fecal calprotectin levels of 324 µg/g at 6 months, which fell to 180 µg/g at 12 months (P = .005) and 109 µg/g at 18 months (P = .004).
“In our cohort, if colonoscopy was performed at 6 months postoperatively only in patients with [fecal calprotectin] concentrations greater than 100 µg/g, then 47% of patients without endoscopic disease recurrence would have avoided a colonoscopy,” the researchers wrote.
“The role of [fecal calprotectin] in assessing postoperative recurrence has been debated owing to inconsistent results in mainly small studies. The strengths of the present study are its large size, prospective measurements, endoscopic validation, and longitudinal interindividual measurements of [fecal calprotectin],” according to an accompanying editorial co-written by Alain M. Schoepfer, MD, from Centre Hospitalier Universitaire Vaudois in Switzerland, and James D. Lewis, MD, from Perelman School of Medicine at University of Pennsylvania in Philadelphia.
“In summary, [fecal calprotectin] has a potential role in the noninvasive monitoring of CD patients after intestinal resection,” they wrote. “The test performance of [fecal calprotectin] in detecting postoperative recurrence is clearly superior to [C-reactive protein] and the CDAI.” – by Adam Leitenberger
Disclosure: Wright reports no relevant financial disclosures, but some of the other researchers report financial associations with Abbott, Janssen and Schering-Plough. Lewis reports he has served as a consultant for AbbVie, Amgen, AstraZeneca, Immune Pharmaceuticals, Janssen Pharmaceuticals, Medimmune, Merck, Nestle Health Sciences and Takeda; has served on a data and safety monitoring board for clinical trials sponsored by Pfizer; and has received research support from Bayer, Nestle Health Sciences, Shire and Takeda. Schoepfer reports he has served as a consultant for AbbVie, Merck, Takeda, Tillotts and UCB; and has received research support from AstraZeneca, Merck, Nestle Health Sciences and Tillots.