Amyloidosis

Background

  • Accumulation of proteins (amyloid fibrils) in tissues
  • Heart and kidneys most commonly affected organs
  • Causes:
    • Primary amyloidosis, hereditary amyloidosis
    • Secondary (due to systemic inflammatory condition)
    • ESRD-associated (caused by β2-microglobulin amyloids, not filtered out by dialysis membranes))
    • Senile amyloidosis (causes cardiac amyloid)

Clinical Features

  • Nephrotic syndrome with kidney involvement
  • Restrictive cardiomyopathy
  • Sensory and autonomic neuropathies (no CNS involvement)
    • Sensory neuropathy: symmetrical pattern, progresses distal to proximal
    • Autonomic neuropathy: orthostatic hypotension or nonspecific GI symptoms
  • Hepatomegaly, elevated serum AST and AlkPhos
  • Diabetes secondary to pancreatic infiltration
  • Macroglossia

Differential Diagnosis

Evaluation

  • Evaluate for other causes of symptoms
  • Diagnosis via fat pad biopsy: apple-green birefringence with Congo red stain

Management

Disposition

See Also

External Links

References