title: Evaluation of in vitro efficacy of combined riboflavin and ultraviolet a for Acanthamoeba isolates.
abstract: OBJECTIVE
  To evaluate in vitro the amoebicidal effects of riboflavin and ultraviolet A (UVA) collagen cross-linking.
  
  
  METHODS
  Experimental study, laboratory investigation.
  
  
  METHODS
  Two different strains of Acanthamoeba species were tested identically. Four treatment groups were considered: group 1 consisted of 0.1% riboflavin and 30-minute UVA irradiation; group 2 consisted of 0.1% riboflavin and 60-minute UVA irradiation; group 3 consisted of no riboflavin and no UVA exposure; group 4 consisted of 0.1% riboflavin and no UVA exposure. The application of UVA was performed under the parameters used for in vivo corneal collagen cross-linking.
  
  
  RESULTS
  In all cases, cysts and trophozoites were detected 24 hours after treatment at a radial distance from the center of the seeding point more than 5 mm, indicating that the amoebae were viable. All treated and untreated groups of amoebae from the 2 strains exhibited growth (radii of 14 to 15 mm in groups 1, 3, and 4; radius of 12 mm in group 2). The final morphologic features of the 2 strains of trophozoites that received treatment were similar to those of the initial seeding group and the untreated control group.
  
  
  CONCLUSIONS
  The results obtained in our study show that a single dose (30 or 60 minutes) of cross-linking cannot achieve eradication in the 2 different Acanthamoeba strains examined. However, in vitro results do not always indicate in vivo efficacy, so future studies should test the validity of this treatment for Acanthamoeba keratitis.
authors: Department of Ophthalmology, "Lozano Blesa" Clinical University Hospital, Zaragoza, Spain. madelbuey@telefonica.net
authors: María A
authors: MA
authors: del Buey
authors: José A
authors: JA
authors: Cristóbal
authors: Paula
authors: P
authors: Casas
authors: Pilar
authors: P
authors: Goñi
authors: Antonio
authors: A
authors: Clavel
authors: Enrique
authors: E
authors: Mínguez
authors: Elena
authors: E
authors: Lanchares
authors: Alicia
authors: A
authors: García
authors: Begoña
authors: B
authors: Calvo
mesh_terms: D000048:Acanthamoeba / Q000187:drug effects* / Q000502:physiology / Q000528:radiation effects; D000818:Animals; D000981:Antiprotozoal Agents / Q000627:therapeutic use*; D003432:Cross-Linking Reagents / Q000627:therapeutic use*; D021261:Parasitic Sensitivity Tests; D010778:Photochemotherapy; D017319:Photosensitizing Agents / Q000627:therapeutic use*; D012256:Riboflavin / Q000627:therapeutic use*; D013997:Time Factors; D016896:Treatment Outcome; D014466:Ultraviolet Rays
chemical_list: D000981:Antiprotozoal Agents; D003432:Cross-Linking Reagents; D017319:Photosensitizing Agents; D012256:Riboflavin