title: Evaluation of papillomaviruses associated with cyclosporine-induced hyperplastic verrucous lesions in dogs.
abstract: OBJECTIVE
  To determine whether cyclosporine A-induced hyperplastic skin lesions of dogs were associated with papillomavirus infections.
  
  
  METHODS
  9 dogs that were treated with cyclosporine A and developed hyperplastic skin lesions.
  
  
  METHODS
  History and clinical and histopathologic data were collected. Paraffin-embedded skin biopsy specimens from hyperplastic skin lesions were immunostained for common papillomavirus genus-specific structural antigens by use of a polyclonal rabbit anti-bovine papillomavirus type 1 antiserum. Sections from each tissue block underwent DNA extraction, and polymerase chain reaction (PCR) assays were performed with several sets of primers to amplify a wide range of papillomavirus DNA from humans and other animals.
  
  
  RESULTS
  In 7 of 9 dogs, there were more than 10 hyperplastic skin lesions that microscopically resembled those of psoriasiform lichenoid dermatosis. In those dogs, results of testing for papillomavirus via immunohistochemical analyses and PCR assays were negative. In the other 2 dogs, there were only 1 and 3 verrucous lesions, and in those dogs, histologic evaluation revealed koilocytes and nuclear viral inclusions that were immunoreactive for papillomavirus antigens. Papillomavirus DNA was amplified from both dogs. One of the sequences was characteristic for the canine oral papillomavirus, whereas the other had similarities with the recently described canine papillomavirus 2.
  
  
  CONCLUSIONS
  In dogs, hyperplastic skin lesions occasionally develop during treatment with cyclosporine A. Most of the lesions resemble those of psoriasiform lichenoid dermatosis, although papillomavirus can be detected in some instances.
authors.affiliation: Clinic for Small Animal Internal Medicine, Dermatology Unit, Vetsuisse Faculty, University of Zürich, Switzerland.
authors.forename: Claude
authors.initials: C
authors.lastname: Favrot
authors.forename: Thierry
authors.initials: T
authors.lastname: Olivry
authors.forename: Alexander H
authors.initials: AH
authors.lastname: Werner
authors.forename: Gilles
authors.initials: G
authors.lastname: Nespecca
authors.forename: Anna
authors.initials: A
authors.lastname: Utiger
authors.forename: Paula
authors.initials: P
authors.lastname: Grest
authors.forename: Mathias
authors.initials: M
authors.lastname: Ackermann
mesh_terms: D000818:Animals; D016572:Cyclosporine / Q000633:toxicity*; D017931:DNA Primers; D004283:Dog Diseases / Q000139:chemically induced* / Q000473:pathology / Q000821:virology*; D004285:Dogs; D007150:Immunohistochemistry; D027383:Papillomaviridae / Q000235:genetics*; D017422:Sequence Analysis, DNA; D014860:Warts / Q000139:chemically induced / Q000473:pathology / Q000662:veterinary* / Q000821:virology
chemical_list: D017931:DNA Primers; D016572:Cyclosporine