Deposition of misfolded and insoluble fibrous proteins in normal organs and tissues
Classification of Amyloidosis
Type Precursor Causative diseases Main organs affected
AL (Primary) Most common ~2000 cases/y Monoclonal Ig light chain MM
Light chain disease (λ> κ)
Renal, cardiac, GI, neuro, cutaneous, hepatic, pulmonary
AA (Secondary) Serum amyloid A (SAA) Inflam: RA, IBD, FMF
Chronic infxns: osteo, TB
Renal, GI, hepatic, neuro, cutaneous
Hereditary ↑ incid Afr Am Mutant TTR, etc. Mutant proteins Neurologic, cardiac
Senile Normal TTR Normal