Pathological proteinaceous substance
deposited extracellularly. May encroach on cells
and produce pressure atrophy.
- amorphous, hyaline
- pink-red, eosinophilic
Congo Red stain: Apple-green, birefringent.
Composed of stacked beta-sheets. Derived from many
different proteins, but all have this common structure.
Type of amyloid in brackets ().
- Myeloma (AL κ or λ)
- Reactive (AA)
- ankylosing spondylitis
- familial Mediterranean Fever
- Chronic infection
- chronic osteomyelitis
- Familial amyloidotic neuropathy (ATTR)
- Haemodialysis-associated amyloidosis (β2-microglobulin)
- medullary thyroid Ca (ACal)
- Endocrine disorders
- Diabetes Mellitus Type 2 (AIAPP)
- isolated atrial amyloidosis (AANF)
- senile cerebral: Alzheimer's disease (βA4)
- senile cardiac (ATTR)
AL = amyloid light chain
AA = amyloid assiciated [protein]
ATTR = amyloid transthyretin
ACal = amyloid procalcitonin
AIAPP = amyloid islet associated polypeptide
May be clinically silent.