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This information is provided by Provet for educational purposes only.

You should seek the advice of your veterinarian if your pet is ill as only he or she can correctly advise on the diagnosis and recommend the treatment that is most appropriate for your pet.

Amyloidosis is a poorly understood systemic disease that can mimic other diseases when it affects specific major organ systems.

Amyloid is a dense, white, opaque, fibrillar glycoprotein that is formed from precursor proteins in a variety of tissues. It is recognised on histological examination as a homogeneous staining material. Amyloid itself is inert and it does not stimulate a local inflammatory reaction however it does damage tissue structure resulting in loss of normal function.

Amyloid is most frequently deposited in the following organs :

  • Adrenal glands
  • Kidneys
  • Liver
  • Lymph nodes
  • Spleen

In the most common form of amyloidosis (called reactive-systemic amyloidosis) the amyloid precursor protein is formed by the liver in response to infection, inflammation or neoplasia. Amyloid is also formed following excess immunoglobulin synthesis, such as occurs in multiple myeloma (rare). Hyperglobulinemia is often present. 

Some authors have suggested an association between the administration of corticosteroids or ascorbic acid and the disease. Experimentally the disease has been induced by feeding cheese, by injecting sodium caseinate , and by repeated antigen challenges such as the repeated injection of dead or living bacteria. The disease also occurs in horses used to produce antitoxins.

Amyloidosis is a progressive disease which is seen most often in dogs and horses and the clinical signs reflect the local tissue injury and loss of organ function, so :

  • Organs increase in size due to amyloid deposition...hepatomegaly, splenomegaly
  • Renal proteinuria (nephrotic syndrome) and/or chronic renal failure occurs - seen in older dogs
  • Thromboembolism is reported to occur (especially in pulmonary arteries) in up to 40% of cases and can result in sudden death

Diagnosis is confirmed by histological examination of biopsies . 

There is no satisfactory treatment for amyloidosis and most patients die within a few months of the diagnosis being confirmed. Any underlying cause (such as the present of sepsis) should be treated, and otherwise symptomatic treatment can be given (eg dietary management for renal and hepatic diseases).

Corticosteroids are contraindicated because they increase the rate of amyloid deposition. 

Two potential forms of treatment have not been fully evaluated yet :

  • Dimethyl sulphoxide has been reported to dissolve amyloid, and 
  • Colchicine has been reported to prevent amyloid deposition


Updated January 2016