title: Calcinosis cutis in dogs: histopathological and clinical analysis of 46 cases.
abstract: BACKGROUND
  Calcinosis cutis is well recognized in dogs with endogenous hyperglucocorticism and iatrogenic hyperglucocorticism, but the pathogenesis is still unclear.
  
  
  OBJECTIVE
  The objectives of the study were to identify possible correlations between histopathological patterns of dermal mineralization in skin biopsies and underlying causes for calcinosis cutis in dogs, as well as to determine breed predilection and age of onset for dogs within a hospital population. In addition, mineral analysis was performed on four biopsy samples.
  
  
  METHODS
  Forty-six dogs with histopathologically confirmed calcinosis cutis were evaluated.
  
  
  METHODS
  Medical records and histological sections of dogs with calcinosis cutis diagnosed by histopathology over a 21 year period were reviewed. Infrared spectrometry was used to identify the mineral in the paraffin blocks. Exact chi-squared test was used to identify breed predispositions, while a Mann-Whitney U-test was used to identify age correlations.
  
  
  RESULTS
  Labrador retrievers, Rottweilers, boxers and Staffordshire terriers were the breeds most commonly affected in this study. Most dogs had either an exogenous or an endogenous source of corticosteroids, with the exception of five dogs with renal insufficiency. In the majority of cases, mineralization was found throughout the entire dermis. The average age of onset of calcinosis cutis for dogs with endogenous hyperglucocorticism was older than that of dogs with iatrogenic hyperglucocorticism. Using infrared spectrometry, apatite crystals were found to be the source of mineral.
  
  
  CONCLUSIONS
  There was no observable difference in the histopathological pattern of calcinosis cutis from dogs with endogenous hyperglucocorticism versus iatrogenic hyperglucocorticism. While glucocorticoid therapy appears to predispose dogs to developing calcinosis cutis, it remains unclear whether there is a specific dose or combination of factors that initiates the mineral deposition. Furthermore, the mineral deposition in dogs with calcinosis cutis was found to be apatite.
authors.affiliation: William R. Pritchard Veterinary Medical Teaching Hospital, School of Veterinary Medicine, University of California, Davis, CA 95616, USA. kadoerr@ucdavis.edu
authors.forename: Katherine A
authors.initials: KA
authors.lastname: Doerr
authors.forename: Catherine A
authors.initials: CA
authors.lastname: Outerbridge
authors.forename: Stephen D
authors.initials: SD
authors.lastname: White
authors.forename: Philip H
authors.initials: PH
authors.lastname: Kass
authors.forename: Ryoji
authors.initials: R
authors.lastname: Shiraki
authors.forename: Andrea T
authors.initials: AT
authors.lastname: Lam
authors.forename: Verena K
authors.initials: VK
authors.lastname: Affolter
mesh_terms: D000818:Animals; D002114:Calcinosis / Q000473:pathology / Q000662:veterinary*; D004283:Dog Diseases / Q000473:pathology*; D004285:Dogs; D005938:Glucocorticoids / Q000378:metabolism; D012189:Retrospective Studies; D012871:Skin Diseases / Q000473:pathology / Q000662:veterinary*
chemical_list: D005938:Glucocorticoids