title: Dendritiform Keratopathy Associated with Exposure to Polyquarternium-1, a Common Ophthalmic Preservative.
abstract: OBJECTIVE
  To describe dendritiform keratopathy associated with exposure to polyquaternium-1, a common preservative found in contact lens solutions and tear replacement products.
  
  
  METHODS
  Case series.
  
  
  METHODS
  Sixteen patients who demonstrated dendritiform keratopathy during topical ophthalmic exposure to polyquaternium-1.
  
  
  METHODS
  Records were reviewed of all patients diagnosed with dendritiform keratopathy between 1999 and 2014 who had documented exposure to contact lens care disinfecting solutions or artificial tear solutions containing polyquaternium-1. Patients were excluded who had coexisting potential causes for dendritiform keratopathy, such as prior herpes simplex keratitis, varicella-zoster viral keratitis, the linear form of Thygeson's superficial keratitis, epithelial regeneration line, Acanthamoeba keratitis, mucus plaque keratopathy, medication-related keratopathy, or limbal stem cell deficiency characterized by conjunctivalization of the corneal epithelium.
  
  
  METHODS
  Effect of discontinuation of exposure to polyquaternium-1 on the dendritiform keratopathy.
  
  
  RESULTS
  Sixteen patients demonstrated dendritiform keratopathy after exposure to the preservative polyquaternium-1. Thirteen patients had a history of recent exposure to contact lens disinfecting solutions (Opti-Free, Equate) containing polyquaternium-1. Three patients used a tear replacement product (Systane) containing a polyquaternium-1 preservative. Four patients were treated with antiviral medications for presumed herpes simplex keratitis; 4 patients underwent diagnostic testing for Acanthamoeba keratitis. Two additional patients were diagnosed sequentially with herpes simplex keratitis, then Acanthamoeba keratitis before referral. All dendritiform lesions resolved within 2 to 6 weeks after elimination of exposure to polyquaternium-1.
  
  
  CONCLUSIONS
  Ophthalmic products containing polyquaternium-1 may cause dendritiform keratopathy that may be confused with infections of the superficial cornea, such as herpes simplex virus keratitis or Acanthamoeba keratitis.
authors.affiliation: Department of Ophthalmology, Baylor College of Medicine, Houston, Texas. Electronic address: amatoba@bcm.edu.
authors.forename: Alice Y
authors.initials: AY
authors.lastname: Matoba
authors.affiliation: Department of Ophthalmology and Visual Science, University of Texas Health Science Center, Houston, Texas.
authors.forename: Jeff R
authors.initials: JR
authors.lastname: Peterson
authors.affiliation: Department of Ophthalmology, Baylor College of Medicine, Houston, Texas.
authors.forename: Kirk R
authors.initials: KR
authors.lastname: Wilhelmus
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003231:Conjunctivitis / Q000139:chemically induced / Q000175:diagnosis; D018639:Contact Lens Solutions / Q000009:adverse effects*; D003263:Contact Lenses, Hydrophilic; D003315:Cornea / Q000187:drug effects* / Q000473:pathology; D003316:Corneal Diseases / Q000139:chemically induced* / Q000175:diagnosis; D004202:Disinfectants / Q000009:adverse effects*; D005260:Female; D006801:Humans; D065346:Lubricant Eye Drops / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D009883:Ophthalmic Solutions; D011108:Polymers / Q000009:adverse effects*; D011310:Preservatives, Pharmaceutical / Q000009:adverse effects*; D055815:Young Adult
chemical_list: D018639:Contact Lens Solutions; D004202:Disinfectants; D065346:Lubricant Eye Drops; D009883:Ophthalmic Solutions; D011108:Polymers; D011310:Preservatives, Pharmaceutical; C058655:polyquaternium 1