Abstract
In September, 1965, formalin-fixed specimens collected from six dead minks (pearl, sapphire, and violet) in Miyagi Prefecture were examined histopathologically and a diagnosis of Aleutian disease was made. Later on, additional specimens came from ten minks of the same farm which had given positiv iodine agglutination tests and, were subjected to autopsy and histopathological examination.
The principal lesions consisted of plasma-cell infiltration in the liver, spleen, kidney, and other organs, changes in blood vessels, including small arteries, in the liver, kidney, lung, and brain, and glomerular changes.
Histochemically, there were abnormal plasma cells containing Russell bodies in the cytoplasm (grape cells). Vascular changes were segmental in distribution. There were also intimal proliferation, accumulation of mononuclear cells, and deposition of fibrinoid in the arteriolar media. Acid mucopolysaccharides (AMP) were detected from the vascular fibrinoid together with PAS-positive materials.
In most of the cases, the glomerular lesions consisted of thickening of the mesangium resulting in an increased lobulation and narrow capillary lumina. Some of them, however, had wire-loop lesions characterized by thickening of the basement menbrane, and nodular lesions with deposition of homogeneous PAS-positive materials. No AMP were detected from the altered glomeruli, except the essentially normal basement membrane.
