This report concerns a patient with systemic amyloidosis due to a plas
mocytoma, in whom massive amyloid depositions in the small bowel cause
d severe diarrhoea and malabsorption. The excessive amyloid deposition
s in the lamina muscularis propria of the bowel finally resulted in th
erapy-resistant motility disturbance and adynamic sibelius with fatal
outcome.