P302 Faecal calprotectin correlates with small bowel inflammatory activity detected by capsule endoscopy in patients with established Crohn’s disease
M. Barbosa*1, S. Monteiro1, T. Gonçalves1, M. J. Moreira1, B. Rosa1, J. Cotter1, 2, 3
1Hospital da Senhora da Oliveira, Gastroenterology, Guimaraes, Portugal, 2Instituto de Investigação em Ciências da Vida e da Saúde, Universidade do Minho, Braga, Portugal, 3Laboratório Associado ICVS/3B´s, Braga, Portugal
Small bowel capsule endoscopy (SBCE) is a very sensitive tool to detect inflammatory lesions in the small bowel. It has a high accuracy for diagnosing small bowel involvement in patients with established Crohn’s disease (CD). The Lewis Score (LS) quantifies and grades small bowel inflammatory activity. The levels of faecal calprotectin (FC) are proportional to neutrophil activity in the enteric lumen; therefore, it is a useful inflammatory biomarker in these patients. The purpose of the study was to investigate the correlation between FC and small bowel inflammatory activity and systemic inflammatory biomarkers, in patients who underwent SBCE for established CD.
We conducted a retrospective study including patients who underwent SBCE for established CD between March and November 2015. Faecal calprotectin, C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR) were measured within 1 week of the exam. The SBCE findings were reviewed by 2 experienced investigators in SBCE. Small bowel inflammatory activity was assessed by LS, classified as significant if LS was ≥ 135 and graded as mild if 135 ≤ LS < 790 or moderate-to-severe if LS ≥ 790. FC was correlated with LS and with CRP or ESR, using Pearson’s correlation. The diagnostic accuracy of FC for significant and moderate-to-severe activity was calculated by the area under the receiver operating characteristic (ROC) (AUROC).
Included were 19 patients: 12 (63%) females, mean age of 35 years. FC correlated positively and significantly to global LS (ρ = 0.705, p < 0.001), to LS sub-score of inflammatory stenosis (ρ = 0.684, p < 0.001), and to LS sub-score of the first tertile of small bowel (ρ = 0.497, p = 0.030). In 15 (79%) patients, SL was ≥ 135, and in 6 (32%), SL was ≥ 790. The AUROC of FC was 0.683 ± 0.141 (0.407–0.960) for significant activity and 0.795 ± 0.114 (0.547–1.000) for moderate-to-severe activity. FC correlated positively to CPR (ρ = 0.623, p = 0.004) and ESR (ρ = 0.598, p = 0.007).
In patients with established CD, faecal calprotectin correlates to small bowel inflammatory activity and to systemic inflammatory biomarkers. Consequently, it can be regarded as a biomarker of small bowel inflammatory lesions detected by SCBE. FC performed well at predicting moderate-to-severe inflammatory activity.