Role of Fecal Calprotectin in Patients Presenting to the Emergency Department with Abdominal Pain with or without Diarrhea or Rectal Bleeding

Background and Objective: Abdominal pain is a frequent reason for admission to the Emergency Department. It may be a symptom of an underlying "organic" disease or a "functional" manifestation without an underlying anatomic or physiologic alteration. The evaluation of patients with abdominal pain is a challenge for the emergency physician and the selection of patients for second-level radiological examinations or endoscopic procedures is not always easy to perform. Faecal calprotectin could be a useful diagnostic marker to distinguish between "organic" or "functional" form and its determination could be helpful to select patients for further examinations in the context of an emergency setting. Materials and Methods: This is an observational and retrospective study on 146 patients with abdominal pain and/or diarrhea (with or without rectal bleeding) admitted to the Emergency Department of Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, who collected a fecal sample to evaluate fecal calprotectin. We evaluated and correlated the level of fecal calprotectin with the final diagnosis they received. Results: 50/146 patients (34,24%) received a diagnosis of acute diverticulitis, in particular, 14/50 (28%) were complicated and 36/50 (72%) were uncomplicated; 4/146 (2,7%) were cholangitis, 32/146 (21,9%) were colitis, 6/146 (4,1%) gastritis, 42/146 (28,7%), Irritable bowel syndrome and 12/146 (8,2%) Inflammatory bowel disease. For the differential diagnosis between Irriable or inflammatory bowel diseses, our study showed a VPP and a VPN of 100% meanwhile for the differential diagnosis between Acute complicated and uncomplicated diverticulitis, our study showed a VPP of 40% and a VPN of 84%. Conclusion: In the emergency setting, faecal calprotectin could be a helpful marker to select patients with abdominal pain who need second-level radiological examinations or endoscopic procedures, guiding the emergency physician in the evaluation of such a complex and wideranging symptom.