[Amyloidosis. Etiology and clinical manifestations]

Amyloidosis is a disorder of protein metabolism in which autologous proteins are deposited intercellularly as fibrils with characteristic staining properties and ultrastructural features. Amyloid deposits may be focal, localized to a particular tissue or organ, or distributed systemically. Many different chemical forms of amyloid have been identified and amyloid may accumulate as a result of a variety of different pathogenetic mechanisms. Amyloid deposits rarely regress, but rather tend to increase inexorably in size. Since there is no effective therapy for systemic forms of amyloidosis, they carry a poor prognosis in most cases.