Most common forms of systemic amyloidosis
| Amyloid type . | Precursor protein . | Major organ involvement . | |||||
|---|---|---|---|---|---|---|---|
| Heart (bone tracer uptake)* . | Kidney . | Liver . | PNS . | ANS . | ST . | ||
| AL amyloidosis (acquired) | Immunoglobulin light chain | +++ (usually absent, can be intense) | +++ | ++ | + | + | ++ |
| ATTRv amyloidosis (hereditary) | Mutated transthyretin | +++ (usually intense, can be absent in some variants) | — | — | +++ | +++ | — |
| ATTRwt amyloidosis (acquired) | Wild-type transthyretin | +++ (usually intense) | — | — | — | — | + |
| ApoAI amyloidosis (hereditary) | Mutated apolipoprotein AI | + (present) | + | +++ | — | — | — |
| AA amyloidosis (acquired) | Serum amyloid A protein | + | +++ | + | — | + | — |
| ALECT2 (acquired) | Leukocyte chemotactic factor 2 | — | +++ | + | — | — | — |
| Amyloid type . | Precursor protein . | Major organ involvement . | |||||
|---|---|---|---|---|---|---|---|
| Heart (bone tracer uptake)* . | Kidney . | Liver . | PNS . | ANS . | ST . | ||
| AL amyloidosis (acquired) | Immunoglobulin light chain | +++ (usually absent, can be intense) | +++ | ++ | + | + | ++ |
| ATTRv amyloidosis (hereditary) | Mutated transthyretin | +++ (usually intense, can be absent in some variants) | — | — | +++ | +++ | — |
| ATTRwt amyloidosis (acquired) | Wild-type transthyretin | +++ (usually intense) | — | — | — | — | + |
| ApoAI amyloidosis (hereditary) | Mutated apolipoprotein AI | + (present) | + | +++ | — | — | — |
| AA amyloidosis (acquired) | Serum amyloid A protein | + | +++ | + | — | + | — |
| ALECT2 (acquired) | Leukocyte chemotactic factor 2 | — | +++ | + | — | — | — |
In AL amyloidosis, soft tissue involvement can manifest as macroglossia, shoulder pad sign, raccoon eyes, carpal tunnel syndrome, synovial enlargement, and firm, enlarged lymph nodes. In ATTRwt, carpal tunnel and lumbar stenosis are frequently reported.
ANS, autonomic nervous system; PNS, peripheral neuropathic involvement; ST, soft tissue; ATTRv, transthyretin amyloidosis variants; AA, serum amyloid A; ApoAI, apolipoprotein AI; ALECT2, leukocyte chemotactic factor 2 amyloidosis.
Bone tracers validated for the detection of cardiac amyloidosis are 99mTc-diphosphono-propanodicarboxylic acid, 99mTc-pyrophosphate, and 99mTc-hydroxymethylene diphosphonate; +++, ≥50%; ++, 10%-30%; +, ≤10%; −, rare or not involved.