Endoscopic Features of Gastrointestinal Amyloidosis: A Proposed Endoscopic Classification.

Background/Aims: Gastrointestinal amyloidosis (GIA) is a common condition that presents with a variety of endoscopic features. However, the classification of these endoscopic features of GIA and its clinical implications have not been investigated. Methods: The endoscopic findings of 127 patients with GIA were reviewed and classified by three experienced endoscopists. The relationships of the endoscopic classification of GIA with clinical amyloidosis entities, symptoms, and patient outcomes were evaluated. Results: Five distinct types of endoscopic lesion features were identified in GIA patients: protruding, granular, hemorrhagic, ulcerative, and nonspecific. The hemorrhagic type was most common (n=32, 25.2%), followed the by protruding (n=30, 23.6%), ulcerative (n=28, 22.0%), granular (n=20, 15.7%), and nonspecific types (n=17, 13.4%). The protruding type was significantly prevalent in patients with localized amyloidosis (23/49, 71.4%), whereas the hemorrhagic type was the most common in patients with immunoglobulin light chain amyloidosis (20/47, 42.6%), and the ulcerative type was the most common in patients with amyloid A amyloidosis (8/17, 47.1%) (p<0.001). The granular type was related to dysmotility symptoms (p=0.018). Among 30 GIA patients with the protruding type, two died, whereas 36.1% of patients with the other endoscopic types (35/97) died during a median follow-up of 95.5 months (interquartile range, 65.8 to 132.0 months) (p=0.007). Conclusions: Five types of GIA lesions were identified, and on this basis, an endoscopic classification system was proposed. This system may be of diagnostic and prognostic value.