Perfil dos marcadores de atividade inflamatória intestinal e correlação com os diferentes graus de atividade endoscópica, avaliados pelo escore endoscópico simplificado na doença de Crohn (SES-CD)

Abstract

Introduction: Effective control of the inflammatory process in Crohn’s disease (CD) is reflected on intestinal mucosal healing, current treatment goal, resulting in less complication rates. The evaluation of the performance of clinical, laboratory, and fecal calprotectin (fCal) in inflammatory activity evaluation, as well as their correlation to the simple endoscopic score (SES-CD) and joint evaluation of fCal and serum C-reactive protein (CRP) in the diagnosis of inflammation in patients with CD, are the goals of this study. Methods: Patients with CD referred for ileocolonoscopy were prospectively included and distributed according to the degree of endoscopic inflammatory activity into: group 1 – remission; group 2 – mild activity; and group 3 – moderate to severe activity. The different degrees of endoscopic activity were correlated to the following indexes: Crohn’s disease activity index (CDAI), fecal calprotectin (fCal), serum C-reactive protein (CRP), and hemogram. The control group was composed of individuals referred to colorectal cancer screening without known intestinal disease. Results: Eighty colonoscopies were performed in patients with CD and 21 in the control group. The control group had a lower median fCal (59.7mcg/g) than patients with CD (683mcg/g, p<0.001) and patients with CD who were in endoscopic remission (236.6mcg/g, p=0.019). Moderate Spearman correlation occurred between SES-CD and CRP (r=0.525), fCal (r=0.450), and CDAI (r=0.407), while weak correlation was found with platelet count (r=0.257). CRP, fCal, and platelet count were able to differentiate between patients in remission and those with mild activity; however, only fCal distinguished patients in remission from those with mild activity (236.6mcg/g x 654.9mcg/g, p=0.014) or moderate to severe (236.6mcg/g x 1128mcg/g, p<0.001). A fCal cut-off 155mcg/g is sensitive (96%) and accurate (78%) for diagnosis of endoscopic activity.The joint and serial evaluation of fCal and CRP has specificity of 82%. According to the probability of inflammatory activity, different scenarios were used to evaluate the performance of these markers and a follow-up algorithm of patients with CD was proposed. Conclusion: Fecal calprotectin presented greatest diagnostic accuracy for endoscopic activity of patients with CD, moderate correlation to SES-CD, and capacity to discriminate patients in remission from those with mild or moderate to severe activity.Serial use of fCal and PCR leads to greater specificity in the diagnosis of endoscopic activity.