Phase angle (PhA) is a biometric parameter measured by bioimpedance analysis (BIA), which reflects organism cellularity and tissues hydration. In addition, since it correlates with the presence of inflammation and the nutritional status, it could be useful to monitor inflammatory bowel disease (IBD) activity. The aim of this study was to establish the potential use of PhA as a new non-invasive and sensitive marker correlated with mucosal healing and/or IBD activity.

Currently, fecal calprotectin is considered the best indirect marker inversely correlated with the mucosal healing in patients with inflammatory bowel disease (IBD). C reactive protein (CRP), is less reliable than fecal calprotectin in the evaluation of IBD activity. In order to establish the potential use of phase angle (PhA) as a new non-invasive and sensitive marker of mucosal healing and/or disease activity in patients with IBD, patients with diagnosis of chronic inflammatory bowel diseases (IBD) according to the European Crohn's and Colitis Organization (ECCO) guidelines will be enrolled. In these patients, the following parameters will be evaluated: age, sex, body mass index (BMI), percentage of weight loss in the last 6 months, duration of illness, location of disease, any previous intestinal surgery, ongoing therapy for IBD, activity disease by clinical scores, CRP, fecal calprotectin, disease activity by endoscopic scores, PhA and fat free mass (FFM).

Inclusion Criteria:

• histological report confirming the diagnosis of IBD,
• value of C-reactive protein (CRP)
• fecal calprotectin,
• colonoscopy within 3 months from the enrollment.

Exclusion Criteria:

• presence of ascites or edema,
• chronic or autoimmune inflammatory diseases,
• ongoing infections,
• recent surgery (in the last 6 months),
• neoplastic diseases,
• ongoing enteral or parenteral nutrition,
• presence of fistulae,
• ileostomy or colostomy,
• short bowel syndrome,
• pregnancy or lactation.

Patients with Crohn's disease and patients with Ulcerative Colitis