Major types of systemic amyloidosis
| Type | Disease association | Precursor protein → Misfolding mechanism → Amyloid fibril type | Clinical manifestations |
|---|
| Primary | Plasma cell dyscrasia | Immunoglobulin light chains → Increased production → AL | Nephropathy, hepatosplenomegaly, cardiomyopathy (AL > AA), peripheral neuropathy, macroglossia, skin bruising |
| Secondary | Chronic infection/ inflammation | Serum amyloid A → Increased production → AA | Nephropathy, hepatosplenomegaly, cardiomyopathy (AL > AA), peripheral neuropathy, macroglossia, skin bruising |
| Age related | Elderly men | Transthyretin (prealbumin) → Accumulation over time → ATTR* | Cardiomyopathy, carpal tunnel syndrome, other peripheral neuropathy |
| Dialysis related | End-stage renal disease on dialysis | β2-Microglobulin → Decreased clearance → Aβ2M | Scapulohumeral arthritis, carpal tunnel syndrome |
*ATTR also occurs in a hereditary form that affects younger patients.
Note: carpal tunnel syndrome = CTS; end-stage renal disease = ESRD.