Severe secondary amyloidosis in a dog with dermatomyositis.

A male collie aged 5 years 10 months, which developed dermatomyositis at 2 months of age, died from severe secondary amyloidosis. Amyloid deposition was most severe in renal glomeruli and produced renal failure. Amyloidosis has been reported in man with immune-mediated disorders including rheumatoid arthritis, systemic lupus erythematosus and dermatomyositis. It is possible that the inflammation in this case of familial canine dermatomyositis may have predisposed to the development of amyloidosis.