Slideshows Images Quizzes
font size

Medical Definition of Amyloid

Amyloid: Any of a number of complex proteins that are deposited in tissues and that share selected laboratory features such as a change in the fluorescence intensity of certain aromatic dyes like Congo Red.

The deposition of amyloid occurs in a number of diseases. In many of these, there is disagreement as to whether amyloid causes the disease or is simply a sign of the disease downstream from the cause. (In Alzheimer's disease, those who believe that the deposition of beta-amyloid protein kills neurons are called baptists.)

Amyloid may be deposited widely in the body, as in systemic amyloidosis. Or the deposition of amyloid may be organ-specific and limited, for instance, to the pancreas, as in type 2 diabetes, or the central nervous system, as in Alzheimer's disease, Parkinson's disease, Huntington disease, Creutzfeldt-Jakob disease and bovine spongiform encephalopathy (mad cow disease).

The term amyloid comes from amylo- (starch) + -oid (like) = like starch. This reflects the mistaken identification of the substance as starch based on crude staining techniques.

Source: MedTerms™ Medical Dictionary
Last Editorial Review: 5/13/2016

Drug Medical Dictionary of Terms by Letter

Top RxList Drug News

GI Disorders

Get the latest treatment options.

Use Pill Finder Find it Now See Interactions

Pill Identifier on RxList

  • quick, easy,
    pill identification

Find a Local Pharmacy

  • including 24 hour, pharmacies

Interaction Checker

  • Check potential drug interactions
Search the Medical Dictionary for Health Definitions & Medical Abbreviations

Health Solutions From Our Sponsors