title: Infectious crystalline keratopathy in dogs and cats: clinical, in vivo confocal microscopic, histopathologic, and microbiologic features of eight cases.
abstract: OBJECTIVE
  To describe clinical, in vivo confocal microscopic, histopathologic, and microbiologic features of canine and feline cases of infectious crystalline keratopathy (ICK).
  
  
  METHODS
  Six dogs and two cats with naturally acquired ICK.
  
  
  METHODS
  Medical records of dogs and cats with a clinical diagnosis of ICK were reviewed. Signalment, medical history, clinical findings, and diagnostic evaluations were retrieved, including corneal cytology, histopathology, in vivo confocal microscopy, and microbiology results.
  
  
  RESULTS
  All animals presented with fine, needle-like, and branching white crystalline anterior stromal opacities emanating from corneal facets or corneal epithelial defects. Mild conjunctival hyperemia and anterior uveitis were frequently present. Concurrent ocular and systemic diseases were common, including keratoconjunctivitis sicca, corneal sequestrum, diabetes mellitus, hyperadrenocorticism, and malignant neoplasia. Bacteria, with minimal or absent leukocytes, were identified by cytology and histopathology. Histopathologically, the crystalline corneal opacities corresponded with dense accumulations of bacteria present in the interlamellar stromal spaces and forming cord-like projections within the stroma. In vivo confocal microscopy demonstrated deposits of reflective crystalline or amorphous structures within the stroma with a paucity of associated inflammatory changes. The most frequently cultured bacteria were alpha-hemolytic Streptococcus and Staphylococcus species. Resolution of clinical lesions was achieved in most cases with long-term medical or surgical therapy; however, the initiation of medical treatment was associated with an acute, dramatic onset of severe keratitis and anterior uveitis in some animals.
  
  
  CONCLUSIONS
  Infectious crystalline keratopathy in dogs and cats shares many features with this condition in human patients. Prolonged medical therapy, or surgical intervention, is required for resolution.
authors.affiliation: Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA.
authors.forename: Eric C
authors.initials: EC
authors.lastname: Ledbetter
authors.affiliation: Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA.
authors.forename: Patrick L
authors.initials: PL
authors.lastname: McDonough
authors.affiliation: Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA.
authors.forename: Kay
authors.initials: K
authors.lastname: Kim
mesh_terms: D000818:Animals; D002371:Cat Diseases / Q000382:microbiology / Q000473:pathology / Q000628:therapy; D002415:Cats; D003318:Corneal Opacity / Q000382:microbiology / Q000473:pathology / Q000628:therapy / Q000662:veterinary*; D004283:Dog Diseases / Q000382:microbiology / Q000473:pathology / Q000628:therapy; D004285:Dogs; D005260:Female; D008297:Male; D018613:Microscopy, Confocal
keywords: bacterial keratitis; cat; cornea; dog; in vivo confocal microscopy; infectious crystalline keratopathy