Amyloid deposits in primary systemic amyloidosis are composed of immunoglobulin light chains. Monoclonal proteins or Bence Jones proteins are usually detected. Neurologic symptoms include a sensory peripheral neuropathy, presenting in a stocking and glove distribution. An "idiopathic" carpal tunnel syndrome can also occur.
Systemic findings can be related to the involvement of the heart, muscles, gastrointestinal tract, kidneys, and nerves. Cardiac symptoms and low ECG voltages may develop as a consequence of restrictive cardiomyopathy. Renal involvement with nephrotic syndrome is the most common presentation of immunoglobulin amyloidosis.
Primary systemic amyloidosis may present with skin and/or mucosal lesions before systemic involvement is apparent, providing an early clue to diagnosis.
The incidence of this disease increases with advancing age.
Related topic: AA amyloidosis
E85.9 – Amyloidosis, unspecified
89449005 – Systemic amyloidosis
- Infiltrative disorders and various other causes of purpura. The histology may be subtle, and the dermatopathologist should be alerted so special stains for amyloid in blood vessels can be performed.
- Nodular or localized cutaneous amyloidosis
- Lichen amyloidosis
- Lipoid proteinosis
- Colloid milium
- Solar purpura
- Sebaceous hyperplasia
- Purpura secondary to ASA or over-anticoagulation