Systemic kappa AL amyloidosis associated with bovine leukocyte adhesion deficiency

Histopathologic and immunohistochemical examinations were conducted on a 5- year-old Holstein-Friesian cow with systemic kappa AL amyloidosis associate d with bovine leukocyte adhesion deficiency. Amyloid deposits were present in the perivascular and intercellular spaces of the visceral organs, such a s the liver, kidneys, pancreas, adrenal glands, and upper alimentary tract. Amyloid was stained positively with Congo red with or without 5% potassium permanganate pretreatment and had green birefringence observed under polar ized light. Immunohistochemically, amyloid reacted strongly against anti-bo vine IgG (H+L) and anti-bovine kappa-light chain and reacted weakly against bovine kappa-light chain antibodies but was negative for anti-human amyloi d AA antibody. This is the first description of AL amyloidosis immunohistoc hemically related to immunoglobulin kappa-light chains of precursor protein in cattle.