Amyloid and the gut.

The systemic amyloidoses are serious and potentially fatal disorders caused by deposition of autologous proteins in an abnormal fibrillar from. The clinical features are highly variable but gut involvement is common and random gastrointestinal biopsies are diagnostic in 80% of patients. Presentations include macroglossia, motility disorders, hemorrhage and pseudo-tumors, although amyloid can mimic almost any other gut pathology. Nonspecific mucosal abnormalities are common both radiologically and at endoscopy. Scintigraphy with serum amyloid P component demonstrates and quantifies the systemic amyloid deposits. Therapy that reduces the supply of the amyloid fibril precursor protein can markedly improve prognosis. Intensive nutritional support for malnourished patients, motility-enhancing drugs and octretide for motility disorders, and correction of clotting disorders in bleeding patients are important adjunctive treatments.