Renal amyloidosis (RA) is generally idiopathic but can be associated with chronic inflammation, infection, or neoplasia. Familial amyloidosis has been described in the Chinese shar-pei (CSP) dog. Reactive amyloidosis in the dog is often associated with progressive chronic kidney disease (CKD) with primary glomerular involvement; however, in CSPs renal medullary lesions predominate. Extrarenal amyloid deposition has also been reported. Up to 23% of CSPs are affected by Familial Shar-Pei Fever (FSF), which may predispose CSPs to systemic reactive amyloidosis.

Records of 18 CSPs and 73 non-shar-pei (NSP) dogs with RA were evaluated. The study found that RA presents most commonly with clinical features of CKD in all dogs. A history of neoplastic, inflammatory, infectious or noninfectious disease was present in 64% of all dogs. FSF was described in 44% of the CSPs. Clinical signs of nephrotic syndrome were found to be uncommon and recorded in only 10% of all dogs, all of which were NSPs. There was a high proportion of leukocytosis in the study (61%), likely associated with predisposing inflammatory and neoplastic disease and with the presence of FSF. CSPs developed RA at a relatively younger age when compared with NSPs and presented with more severe azotemia and milder proteinuria. Disseminated amyloidosis with glomerular involvement was more common in CSPs. Creatinine concentration was a prognostic indicator associated with death or euthanasia in both groups.

Commentary
RA can be suspected based upon the presenting clinical features, but renal biopsies are rarely performed. This study helps characterize differences between shar-pei and non-shar-pei dogs, which may help the practitioner when attempting to treat this potentially life-limiting disease. A specific interest in this study was the correlation between inflammation and the presence of disease, illustrating the need for more studies investigating the pathophysiology of RA and the role of inflammation in modulating the disease.—Heather Troyer, DVM, DABVP, CVA

Source
Renal amyloidosis in dogs: A retrospective study of 91 cases with comparison of the disease between shar-pei and non-shar-pei dogs. Segev G, Cowgill LD, Jessen S, et al. J Vet Intern Med 26:259-268, 2012.