A new cutoff value for fecal calprotectin level in differentiating functional from organic causes of chronic diarrhea

Abstract

Background The gold standard to establish inflammatory bowel disease diagnosis remains in the hands of endoscopists and pathologists. A challenge is thus to distinguish symptoms of inflammatory bowel disease from that of irritable bowel syndrome. Aim of this work The aim of this study was to evaluate the clinical usefulness of fecal calprotectin level as a noninvasive marker in order to distinguish patients with diarrhea in need of intensified follow-up from those who do not need further workup. Patients and methods From a total of 150 patients presented with chronic diarrhea with or without bleeding per-rectum in the outpatient clinic of Specialized Medical Hospital, only 60 were involved in this study. Stool analysis and culture were carried out. Measurement of fecal calprotectin was done using the ELISA kit. Inflammatory biomarkers, such as erythrocyte sedimentation rate and C-reactive protein and perinuclear anti-neutrophil cytoplasmic autoantibodies (P-ANCA) and cytoplasmic antineutrophil cytoplasmic antibodies (C-ANCA), were tested. Full colonoscopy with histopathological examination was performed. Results The frequencies of diseases on the basis of diagnostic colonoscopy and pathological examination were as follows: 19 patients with irritable bowel syndrome (31.67%), 41 patients with nonorganic gastrointestinal (GIT) disease versus organic GIT diseases (68.33%), 32 patients with ulcerative colitis (53.33%), two patients with Crohn's disease (3.33%), two patients with diverticulitis (3.33%), two patients with eosinophilic gastroenteritis (3.33%), and two patients with cancer colon (3.33%). There was a remarkable difference between organic GIT diseases versus nonorganic groups as regard fecal level of calprotectin (P Conclusion Calprotectin, a fecal marker, is helpful as an adjunctive tool in overall evaluation of patients with nonspecific symptoms and as a diagnostic tool in those with inflammatory disease. It is less invasive than colonoscopy and can help to guide management in a more cost-effective manner.