Amyloidosis and Neuropathy

  • Probably 1st described in early 18th century-Wainewright described amyloid involving the liver.
  • When stained with Congo red, it produces an apple-green birefringence when viewed under polarized light.
  • Several types of Amyloidosis
    • Primary-no evidence of preceding or coexisting disease except multiple myeloma.
      • Divided into two groups-with/without multiple myeloma.
    • Secondary-coexistence with other conditions such as RA or chronic infection.
    • Localized-involvement of a single organ without evidence of generalized involvement.
    • Familial
    • Senile
    • Endocrine
    • Dialysis arthropathy
  • Cutaneous nerve biopsy is the only certain method to recognize Amyloidosis in a peripheral nerve.
  • Systemic symptoms-weakness, fatigue most frequent occurs 50% of pts. Also ankle edema, hepatomegaly, macroglossia (large tongue), purpura (neck and face, upper eyelids)
  • Carpal tunnel syndrome or peripheral neuropathy found in 1/6 of with primary Amyloidosis, usually present at least one year prior to dx. Peripheral neuropathy involves sensory more than motor, lower extremity more than upper extremity, distal more than proximal. Dysautonomia often severe due to small non-myelinated pathology.
  • Prognosis:  mean duration of pts with primary type within one month of dx at Mayo-13 months. Only 7% survived more than 5 yrs.