Amyloidosis is a generic term for a heterogeneous group of disorders associated with deposition of protein in an abnormal fibrillar form.1 The diverse spectrum of amyloid related diseases is now recognised to include Alzheimer’s disease, type II diabetes, and the transmissible spongiform encephalopathies. Amyloidosis can be hereditary or acquired, localised or systemic, and potentially lethal or merely an incidental finding.

Amyloid deposits consist mainly of protein fibrils, the varying peptide subunits of which constitute the basis for its classification (table1).2 Despite much heterogeneity among their respective precursor proteins, all amyloid fibrils have a remarkably similar adopted ultrastructure and share many physicochemical properties attributable to their acquired rich β-sheet content.3Certain glycosaminoglycans (GAGs) are invariably associated with the fibrils and, in addition, all amyloid deposits contain the normal plasma protein serum amyloid P component (SAP). The specific binding interaction between SAP and all amyloid fibrils is the basis for our development of radiolabelled SAP as a diagnostic nuclear medicine tracer.4 ,5

There have been many recent advances in amyloidosis including elucidation of the structure and properties of amyloid fibrils, the role of GAGs and SAP, and substantial improvements in clinical diagnosis and management. Although a specific generic treatment for the disease is not yet available, compelling evidence that amyloid deposits frequently regress when the supply of the respective fibril precursor protein is reduced has encouraged a much more positive approach to patient care.5