title: Thrombo-ischaemic pinnal necrosis associated with fenbendazole treatment in a dog.
abstract: An 11-week-old, female West Highland white terrier was presented with necrosis of the distal third of both pinnae. Haematology, biochemistry and urinalysis, Coombs test, antinuclear antibody and cold autoagglutinin antibody tests were normal. A drug reaction to fenbendazole was diagnosed. The necrotic ear tips were surgically removed. Histopathology revealed extensive coagulative necrosis of the epidermis and superficial to mid-dermis, a moderate interstitial neutrophilic infiltrate and complete thrombotic occlusion and necrosis of blood vessels. There was also endothelial cell activation and proliferation with endothelial cell cushions protruding into the vascular lumen. Immunohistochemistry for factor VIII-related antigen confirmed endothelial cell involvement. This case represents an unusual, drug-induced, thrombo-ischaemic necrosis of the pinnae. It is also, to the authors' knowledge, the first report of fenbendazole sensitivity in a dog. The histopathology is similar to previous cases of proliferative thrombovascular pinnal necrosis, suggesting that drug reactions should be considered in this condition.
authors.affiliation: Department of Veterinary Clinical Science, The University of Liverpool, Crown Street, Liverpool L7 7EX.
authors.forename: T J
authors.initials: TJ
authors.lastname: Nuttall
authors.forename: R
authors.initials: R
authors.lastname: Burrow
authors.forename: I
authors.initials: I
authors.lastname: Fraser
authors.forename: A
authors.initials: A
authors.lastname: Kipar
mesh_terms: D000818:Animals; D000969:Antinematodal Agents / Q000009:adverse effects* / Q000627:therapeutic use; D004283:Dog Diseases / Q000139:chemically induced* / Q000473:pathology / Q000601:surgery; D004285:Dogs; D004431:Ear, External / Q000473:pathology* / Q000601:surgery; D005260:Female; D005273:Fenbendazole / Q000009:adverse effects* / Q000627:therapeutic use; D007150:Immunohistochemistry / Q000662:veterinary; D009336:Necrosis / Q000139:chemically induced / Q000601:surgery / Q000662:veterinary
chemical_list: D000969:Antinematodal Agents; D005273:Fenbendazole