Familial renal amyloidosis 

Amyloidosis is a disease characterized by the extracellular deposition of protein fibrils which have a specific configuration called the beta-pleated sheet. This configuration leads to the staining properties and insolubility of amyloid. The animal does not mount an inflammatory response to amyloid. Amyloid can be deposited in any organ. Organ malfunction develops as normal tissue is encroached upon by amyloid deposition.

 The location of amyloid deposition in the kidneys differs between dogs and cats and results in different clinical signs in the two species. In the dog kidney, amyloid is deposited adjacent to the glomerular basement membrane resulting in a disruption of the filtration barrier and development of proteinuria. The degree of proteinuria is usually great. Rapid deposition of amyloid may increase the size of the kidneys. As amyloid encroaches on capillary lumen, RBF is decreased, leading to a decrease in GFR and signs of renal failure.

Signelment:   Amyloidosis can occur in any breed of dog or cat. Abyssinian cats and Sharpei dogs develop a familial form of amyloidosis. There is no sex predisposition for the development of amyloid.  Most animals that develop amyloidosis are middle aged to geriatric. Abyssinian cats and Sharpei dogs that develop amyloid can be young.

Diagnosis: The laboratory findings and the clinical picture of amyloidosis in the dog are very similar to glomerulopathy. The clinical picture will also reflect the underlying disease that precipitated amyloid deposition.

Familial renal amyloidosis  occurs in the Abyssinian cat and the Sharpei dog. Amyloidosis has also been reported in young Siamese and Oriental Shorthaired cats. Familial renal amyloidosis in the Sharpei dog is also called Sharpei fever or Sharpei hock syndrome as it begins with episodes of fever and swollen hocks. The fever and joint swelling are self limiting but often reoccur. Signs may develop in pups or adults. Renal and hepatic amyloid deposition leads to renal or hepatic failure. Renal amyloid deposition may be medullary or glomerular.

The prognosis is usually poor. Some dogs can be managed up to 1-5 year. Some Abyssinian cats may be asymptomatic.
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College of Veterinary Medicine,  Washington State University,
Pullman, WA, 99164-7010 USA 
Revised July 27, 2006