Bilateral perirenal fat necrosis in a sambar deer (Rusa unicolor)

• Published in: Pesquisa Veterinária Brasileira
• Main Authors: Ana C.M.R. Bernardo, Telma S. Lima, Silvio M.C. Fonseca, Givaldo B. Silva-Filho, Hisadora A.S.C. Bom, Elizandra T. Melo, João P.G. Silva, Fábio S. Mendonça
• Format: Article in Journal/Newspaper
• Language: English; Portuguese
• Published: Colégio Brasileiro de Patologia Animal (CBPA) 2023
• Subjects: Fat necrosis; adipocytes; mineralization; deer; Rusa unicolor; Veterinary medicine; SF600-1100; Balaena mysticetus
• Online Access: https://doi.org/10.1590/1678-5150-pvb-7254; https://doaj.org/article/bf7780f74cc54bf7b7b9af26ea6f9fad

ABSTRACT: The gross and histopathological findings of perirenal fat necrosis in a sambar deer (Rusa unicolor) are described in a 6-year-old female deer that was necropsied after showing severe apathy, weight loss, recumbency, and death. At post-mortem examination, two large white to yellow, irregular, and encapsulated masses involving both kidneys were observed. Microscopically, these masses consisted of fat tissue presenting multifocal to coalescing areas of necrosis, diffuse infiltration of lymphocytes, macrophages, occasional plasma cells, and multinucleated giant cells. Multifocally, the necrotic sites were replaced by mineralization and fibrosis. The described condition has not been reported in deer and the exact mechanisms of development of perirenal fat necrosis remain to be determined. Massive fat necrosis has been reported in other animal species such as dogs, cats, pigs, goats, cattle, and whales (Balaena mysticetus). It is usually an incidental finding during post-mortem examination that needs to be differentiated from neoplasms originating from the adipose tissue, kidneys and adrenals, and disorders resulting from pancreatitis and obesity.