title: Acanthamoeba keratitis. Contact lens and noncontact lens characteristics.
abstract: OBJECTIVE
  To identify potential differences in time to diagnosis and final visual outcome between contact lens and noncontact lens users with Acanthamoeba keratitis.
  
  
  BACKGROUND
  Prior studies have shown early diagnosis and therapy to be related to outcome but have not analyzed differences among patients with and without contact lenses.
  
  
  METHODS
  A retrospective analysis of 11 consecutive cases (involving 13 eyes) of Acanthamoeba keratitis diagnosed at one institution over a 3-year period.
  
  
  RESULTS
  Mean time to diagnosis was significantly longer in noncontact lens users versus those who wore contact lenses (mean, 5.8 versus 3.3 weeks). Fifty percent of patients who did not wear contact lenses had a poor outcome (visual acuity worse than 20/40 or penetrating keratoplasty) versus 14% of patients who wore contact lenses.
  
  
  CONCLUSIONS
  Diagnoses were made later in patients without contact lenses, and these patients had a worse visual outcome than those with Acanthamoeba keratitis who wore contact lenses. All patients with unresponsive microbial keratitis, even those without contact lens use, should be evaluated for Acanthamoeba.
authors.affiliation: Department of Ophthalmology, Massachusetts Eye & Ear Infirmary, Harvard Medical School, Boston, USA.
authors.forename: E W
authors.initials: EW
authors.lastname: Chynn
authors.forename: M A
authors.initials: MA
authors.lastname: Lopez
authors.forename: D
authors.initials: D
authors.lastname: Pavan-Langston
authors.forename: J H
authors.initials: JH
authors.lastname: Talamo
mesh_terms: D000048:Acanthamoeba / Q000302:isolation & purification; D015823:Acanthamoeba Keratitis / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology / Q000628:therapy; D000293:Adolescent; D000328:Adult; D000818:Animals; D017024:Chemotherapy, Adjuvant; D003261:Contact Lenses / Q000009:adverse effects*; D003315:Cornea / Q000469:parasitology / Q000503:physiopathology; D005260:Female; D006801:Humans; D015948:Keratoplasty, Penetrating; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012307:Risk Factors; D013997:Time Factors; D014792:Visual Acuity