title: Riboflavin and ultraviolet light a therapy as an adjuvant treatment for medically refractive Acanthamoeba keratitis: report of 3 cases.
abstract: OBJECTIVE
  To present the first 3 cases of Acanthamoeba keratitis (AK), unresponsive to medical treatment, that were successfully treated with a novel adjunctive therapy using ultraviolet light A (UVA) and riboflavin (B2).
  
  
  METHODS
  Interventional case series.
  
  
  METHODS
  Two patients with confirmed AK and 1 patient with presumptive AK, which were all refractive to multidrug conventional therapy.
  
  
  METHODS
  Two treatment sessions involving topical application of 0.1% B2 solution to the ocular surface combined with 30 minutes of UVA irradiation focused on the corneal ulcer.
  
  
  METHODS
  Clinical examination by slit lamp, confocal microscopy, and histopathology, when available.
  
  
  RESULTS
  All patients in these series showed a rapid reduction in their symptoms and decreased ulcer size after the first treatment session. The progress of the clinical improvement began to slow after 1 to 3 weeks of the first application and was then renewed after the second application. All ancillary signs of inflammation mostly resolved after the second treatment session. The ulcers in all patients continued to decrease and were closed within 3 to 7 weeks of the first application. Two patients developed dense central corneal scars, and penetrating keratoplasty was performed for visual rehabilitation. Histopathologic examination of the excised tissue revealed no Acanthamoeba organisms. The remaining patient had no symptoms or signs of infection, both clinically and by confocal microscopy, and was left with a semitransparent eccentric scar that did not affect visual acuity.
  
  
  CONCLUSIONS
  The adjunctive use of UVA and B2 therapy seems to be a possible alternative for selected cases of medication-resistant AK.
authors.affiliation: The Wilmer Ophthalmological Institute, The Johns Hopkins University, School of Medicine, Baltimore, Maryland 21205, USA.
authors.forename: Yasin A
authors.initials: YA
authors.lastname: Khan
authors.forename: Renata T
authors.initials: RT
authors.lastname: Kashiwabuchi
authors.forename: Suy Anne
authors.initials: SA
authors.lastname: Martins
authors.forename: Juan M
authors.initials: JM
authors.lastname: Castro-Combs
authors.forename: Sachin
authors.initials: S
authors.lastname: Kalyani
authors.forename: Philip
authors.initials: P
authors.lastname: Stanley
authors.forename: David
authors.initials: D
authors.lastname: Flikier
authors.forename: Ashley
authors.initials: A
authors.lastname: Behrens
mesh_terms: D015823:Acanthamoeba Keratitis / Q000188:drug therapy* / Q000469:parasitology; D000328:Adult; D000981:Antiprotozoal Agents / Q000627:therapeutic use; D001550:Benzamidines / Q000627:therapeutic use; D001645:Biguanides / Q000627:therapeutic use; D017024:Chemotherapy, Adjuvant; D002710:Chlorhexidine / Q000031:analogs & derivatives / Q000627:therapeutic use; D003263:Contact Lenses, Hydrophilic / Q000469:parasitology; D003320:Corneal Ulcer / Q000188:drug therapy* / Q000469:parasitology; D004359:Drug Therapy, Combination; D006801:Humans; D008297:Male; D018613:Microscopy, Confocal; D008875:Middle Aged; D010778:Photochemotherapy; D017319:Photosensitizing Agents / Q000627:therapeutic use*; D012256:Riboflavin / Q000627:therapeutic use*; D014466:Ultraviolet Rays; D014792:Visual Acuity / Q000502:physiology
chemical_list: D000981:Antiprotozoal Agents; D001550:Benzamidines; D001645:Biguanides; D017319:Photosensitizing Agents; C031233:polihexanide; C046651:propamidine isethionate; C010882:chlorhexidine gluconate; D002710:Chlorhexidine; D012256:Riboflavin