Comparison Between Axial- and Lateral-viewing Capsule Endoscopy in Celiac Disease

The study will involve 25 patients with suspected complicated celiac disease , which for clinical reasons are referred for an evaluation of the small intestine by means of capsule endoscopic in order to screen/identify complications. Furthermore, patients under regular follow-up for a known complication of celiac disease (i.e. refractory celiac disease, ulcerative jejunoileitis) will also be enrolled. Patients reffered to the Center for Prevention and Diagnosis of celiac disease at the research Hospital "Fondazione Cà Granda Ospedale Maggiore Policlinico" in Milan will be prospectively evaluated and consecutively enrolled in the study. In agreement with international Guidelines, the diagnosis of celiac disease will be based on Presence of atrophy in the duodenal biopsy sampling (Marsh-Oberhuber type 3) and positive serology or genetic compatibility (in case of seronegative patients at diagnosis). Patients at high risk of celiac disease complications are defined as * subjects older than 50 years at the time of celiac disease diagnosis * subjects with persistence / recurrence of gastrointestinal symptoms after at least 6 months of gluten-free diet * subjects reporting poor compliance to the gluten-free diet * subjects with alarm signs at diagnosis or during follow-up. All enrolled patients will undergo examination of the small bowel by means of both endoscopic capsule devices (the axial-view PillCam SB3 and the lateral-view CapsoCam) on the same day at approximately 3 hours interval from one another, according to a protocol already validated in terms of security in other studies. The order of administration of the two different capsules, will be determined by a specific randomization sequence. At the end of the examination, recorded data from the capsules will be acquired according to the following steps: * For the axial-view capsule: removal of the recorder after 10 hours recording and/or after checking that the capsule has reached the cecum. The patient will also be instructed to retrieve the capsule from the stools in the hours / days following the examination as per standard protocol. * For the lateral-view capsule, the patient will be given a specific kit for its retrieval and conservation. The recorded data will be downloaded after retrieval of the capsule. The 50 videos will be reviewed by three experts operators (L.E., F.B. G.E.T.), blinded and in randomized order. The operators will evaluate the number of lesions detected by the two different types of capsule system (Primary endpoint) and the mean extension of the lesions detected, expressed as percentage of the total transit time of the capsule in the small intestine (Secondary endpoint)