P297 Fecal calprotectin accurately predicts symptomatic relapse in children and adolescents with inflammatory bowel disease in clinical remission
Diederen K.*1, Hoekman D.1, Leek A.2, Wolters V.2, Benninga M.1, Hummel T.3, de Meij T.4, Koot B.1, Tabbers M.1, Benninga M.1, Kindermann A.1
1Department of Pediatric Gastroenterology and Nutrition, Academic Medical Center, Amsterdam, Netherlands 2Department of Pediatric Gastroenterology, University Medical Center Utrecht, Utrecht, Netherlands 3Department of Pediatrics, Medisch Spectrum Twente, Enschede, Netherlands 4Department of Pediatric Gastroenterology, VU University Medical Center, Amsterdam, Netherlands
In children and adolescents with inflammatory bowel disease (IBD) in clinical remission, it is difficult to predict when a relapse will occur. Reliable data on the value of biomarkers of inflammation for predicting relapse in these young patients are lacking. Therefore, we aimed to investigate the predictive value of fecal calprotectin (FC) and CRP for symptomatic relapse in pediatric IBD in clinical remission.
In this cross-sectional cohort study, patients aged <18 years with Crohn's disease or ulcerative colitis in clinical remission ≥3 months were included. At baseline, clinical and biochemical disease activity were assessed using the abbreviated-Pediatric Crohn's Disease Activity Index (aPCDAI) or Pediatric Ulcerative Colitis Activity Index (PUCAI), and FC and CRP, respectively. Clinical remission was defined as an aPCDAI or PUCAI <10. Disease course over the subsequent 12 months was retrospectively assessed. Symptomatic relapse was defined as an aPCDAI or PUCAI score ≥10, with the need for treatment intensification. Multivariate Cox regression analysis was performed to evaluate whether FC and CRP were independent predictors for symptomatic relapse.
In total, 114 patients in clinical remission were included (56% males; median age 14.9 years). Baseline FC level was higher in patients that developed a relapse compared to patients without symptomatic relapse (median 367 μg/g vs. 117μg/g, p=0.014). FC level was an independent predictor for symptomatic relapse within 6 months from baseline (HR per 100μg/g: 1.15 [95% CI: 1.06–1.24], p<0.001), corresponding to a 15% increase in the probability of relapse per 100 μg/g increment, with fair predictive accuracy (AUC: 0.77, p<0.001). The optimal FC cut-off was 350 μg/g, with a sensitivity and specificity of 76% and 78%, respectively.
Baseline CRP level did not differ between patients with or without symptomatic relapse. CRP level was an independent predictor for symptomatic relapse within 6 months from baseline (HR per 1mg/L: 1.10 [95% CI: 1.01–1.19], p=0.025), corresponding to a 10% increase in the probability of relapse per 1 1mg/L increment, with poor predictive accuracy (AUC: 0.67, p=0.036). The optimal CRP cut-off was 0.6 mg/L, with a sensitivity and specificity of 88% and 38%, respectively.
Levels of FC and CRP were both independent predictors of symptomatic relapse in pediatric IBD in clinical remission, with superior predictive test characteristics of FC. High FC levels at routine measurement justify careful disease monitoring and evaluation of current treatment.