Among children with ulcerative colitis (UC), longitudinal fecal calprotectin (FC) changes may be more effective at predicting 1-year outcomes than FC levels at diagnosis. These findings were published in the Journal of Pediatric Gastroenterology and Nutrition.
The predicting response to standardized pediatric colitis therapy (PROTECT) study was conducted at 29 sites between 2012 and 2015. Children (N=352) aged 4 to 17 years with a new diagnosis of UC were assessed by colonoscopy and for FC levels. The primary outcome was ³4-week corticosteroid (CS)-free remission, defined as a Pediatric Ulcerative Colitis Activity Index (PUCAI) score <10, with no medications used other than mesalamine.
The study participants were aged mean 12.6 (SD, 3.3) years, 49.4% were girls, 14.2% were non-White, 16.7% had a family history of inflammatory bowel disease, PUCAI total score was 49.7 (SD, 19.8) points, and FC was 2910.625 (SD, 2491.5) mcg/g.
At week 52, 38.3% of patients achieved CS-free remission and among the 105 patients who had repeat endoscopy, 46.7% achieved endoscopic remission.
Children who achieved CS-free remission at week 52 did not differ at baseline for FC (mean, 2914 mcg/g) compared with those who did not achieve remission (mean, 2908 mcg/g; P =.98). A similar trend was observed for any remission compared with no remission (mean, 2912 vs 2910 mcg/g; P =.99), among those who required escalation to anti-tumor necrosis factor (TNF) therapy compared with those who did not (mean, 3153 vs 2794 mcg/g; P =.31), and those who underwent colectomy or not (mean, 2763 vs 2920 mcg/g; P =.83).
At week 4, FC was significantly lower among patients who achieved remission at week 52 (mean, 1079 vs 1554 mcg/g; P =.006). The difference in FC remained significant at week 12 (mean, 884 vs 1752 mcg/g; P <.0001).
Every 250 mcg/g increase in FC at week 12 corresponded with decreased odds of obtaining CS-free remission (odds ratio [OR], 0.91; 95% CI, 0.87-0.96) or any remission (OR, 0.91; 95% CI, 0.87-0.96) and increased risk for needing anti-TNF treatment (OR, 1.10; 95% CI, 1.05-1.15) or colectomy (OR, 1.05; 95% CI, 1.00-1.09).
Similarly, children who had a >75% decrease in FC at week 12 were associated with a 3-fold increased likelihood of achieving CS-remission compared against those with a <25% decrease (OR, 3.48; 95% CI, 1.39-8.69). A similar trend was observed among the subset of children who received corticosteroids.
This study was limited by the large amount of missing data, in which only 65% of patients provided serial FC samples at baseline and weeks 4 and 12.
This study found that changes in FC over time or at weeks 4 and 12 were better predictors of outcomes than baseline FC. Additional studies with FC samples collected at more frequent intervals are needed to determine optimal sampling strategies for predicting UC outcomes.
Krishnakumar C, Ananthakrishnan AN, Boyle BM, et al. Early change in fecal calprotectin predicts one-year outcome in children newly diagnosed with ulcerative colitis. J Pediatr Gastroenterol Nutr. 2022;74(1):72-78. doi:10.1097/MPG.0000000000003291