Massive intestinal hemorrhage associated with intestinal amyloidosis. An investigation of underlying pathologic processes.

Abstract

Various factors could be involved in causing massive intestinal hemorrhage in systemic amyloidosis. Functional disturbances may be involved due to amyloid deposition in relation to blood vessels, lymphatics, nerves, and nerve plexuses, and, as it appeared to be the case in the two surgical specimens investigated, massive deposition in the muscularis mucosae. The reduced motility and increased rigidity of the musculature probably result in shearing forces being set up in the presence of mechanical strain (eg in coprostasis or colonoscopy) that lead to tears in the region of the muscularis mucosae and to massive hemorrhage. Intestinal hemorrhage in amyloidosis may also be related to disturbances of coagulation, which have been reported in occasional cases, and ulceration, probably resulting in some cases of ischemic colitis.