The Role of Combining Biochemical Markers in Assessing the Endoscopic Activity in Ulcerative Colitis

Abstract

Ulcerative colitis (UC) isa chronic, idiopathic and recurrent inflammatory bowel disease (IBD), characterized by periods of activity and remissionwhose monitoring requires invasive explorations associated with discomfort for the patient and important costs. Mucosal healing became one of the most important therapeutic targets in UC. The aim of our study was to identify a score, made up of noninvasive, available, used in current clinical practice biochemical markers, which should correlate with endoscopic activity in UC. We conducted a prospective study on 114 patients with UC. All patients were assessed both for biological inflammatory markers: erythrocyte sedimentation rate (ESR),C- reactive protein (CRP), fibrinogen, platelets, albumin, fecal calprotectin (FC) and by colonoscopy to estimate the endoscopic activity using Mayo score. By linear regression, we tried to identify a biochemical score correlated with endoscopic activity. Out of the serological markers,ESR (p=0.014), CRP(p= 0.021) and fibrinogen (p=0.035) correlated with the endoscopic activity of the disease. The best sensitivity to determine the endoscopic activity was given by FC (96.05%) with a predictable negative value of 91.1% (p=0.001). The score determined by linear regression: 1 (ESR]15mm/1h) x 0.305 + 1(fibrinogen]340.5mg/dL) x 0.309+1 (CRP] 5 mg/L) + 1 (calprotectin]200 μg/g) had an increased positive predictive value compared to each and one biomarker, nevertheless, with a sensitivity and specificity inferior to that of FC. Up to now, it is the first attempt to achieve a score made up exclusively of biological markers. The obtained score, although with an increased accuracy, has proven to have a lower predictability in comparison with FC used individually and cannot entirely replace colonoscopy.