title: Crescentic glomerulonephritis in a polar bear (Ursus maritimus).
abstract: Spontaneous crescentic glomerulonephritis (CrGN) in animals has only been reported in dog and sheep. We report the pathological features of CrGN in a 17-year-old male polar bear that died due to renal failure. Histologically, the lesions were characterized by fibrocellular crescents, adhesion between Bowman's capsule and the glomerular capillary tuft and an increase in the mesangial matrix in glomeruli. The proliferating cells in the crescent were partly immunopositive for cytokeratin and intensely positive for vimentin, WT-1 and α-smooth muscle actin, suggesting they originated from parietal epithelial cells. Ultrastructually, thickening of the glomerular basement membrane and loss of epithelial cell foot processes were observed with electron-dense deposits.
authors.affiliation: Laboratory of Veterinary Pathology, School of Veterinary Medicine, Azabu University, Sagamihara, Kanagawa 252-5201, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Baba
authors.forename: Tomoo
authors.initials: T
authors.lastname: Kudo
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Makino
authors.forename: Yasumasa
authors.initials: Y
authors.lastname: Mochizuki
authors.forename: Takayo
authors.initials: T
authors.lastname: Takagi
authors.forename: Yumi
authors.initials: Y
authors.lastname: Une
mesh_terms: D000818:Animals; D017809:Fatal Outcome; D005921:Glomerulonephritis / Q000473:pathology / Q000662:veterinary*; D007150:Immunohistochemistry / Q000662:veterinary; D008297:Male; D008854:Microscopy, Electron / Q000662:veterinary; D001503:Ursidae