title: Determination of minimal erythema dose and anomalous reactions to UVA radiation by skin phototype.
abstract: BACKGROUND
  Phototesting is a technique that assesses the skin's sensitivity to UV radiation by determining the smallest dose of radiation capable of inducing erythema (minimal erythema dose [MED]) and anomalous responses to UV-A radiation. No phototesting protocol guidelines have been published to date.
  
  
  METHODS
  This was a multicenter prospective cohort study in which 232 healthy volunteers were recruited at 9 hospitals. Phototests were carried out with solar simulators or fluorescent broadband UV-B lamps. Each individual received a total of 5 or 6 incremental doses of erythemal radiation and 4 doses of UV-A radiation. The results were read at 24hours.
  
  
  RESULTS
  At hospitals where solar simulators were used, the mean (SD) MED values were 23 (8), 28 (4), 35 (4), and 51 (6) mJ/cm(2) for skin phototypes i to iv, respectively. At hospitals where broadband UV-B lamps were used, these values were 28 (5), 32 (3), and 34 (5) mJ/cm(2) for phototypes ii to iv, respectively. MED values lower than 7, 19, 27, and 38 mJ/cm(2) obtained with solar simulators were considered to indicate a pathologic response for phototypes I to IV, respectively. MED values lower than 18, 24, and 24mJ/cm(2) obtained with broadband UV-B lamps were considered to indicate a pathologic response for phototypes ii to iv, respectively. No anomalous responses were observed at UV-A radiation doses of up to 20J/cm(2).
  
  
  CONCLUSIONS
  Results were homogeneous across centers, making it possible to standardize diagnostic phototesting for the various skin phototypes and establish threshold doses that define anomalous responses to UV radiation.
authors.affiliation: Servicio de Dermatología, Hospital General Universitario de Valencia, Valencia, España. Electronic address: perez_ampferr@gva.es.
authors.forename: A
authors.initials: A
authors.lastname: Pérez Ferriols
authors.affiliation: Unidad de Fotobiología Dermatológica y Oncología Cutánea, Departamento de Dermatología y Medicina, Universidad de Málaga, Málaga, España.
authors.forename: J
authors.initials: J
authors.lastname: Aguilera
authors.affiliation: Servicio de Dermatología, Hospital Clínic de Barcelona, Barcelona, España.
authors.forename: P
authors.initials: P
authors.lastname: Aguilera
authors.affiliation: Servicio de Dermatología, Hospital Universitario de La Princesa, Madrid, España.
authors.forename: D
authors.initials: D
authors.lastname: de Argila
authors.affiliation: Servicio de Dermatología, Hospital Sta. Creu i St. Pau, Barcelona, España.
authors.forename: M A
authors.initials: MA
authors.lastname: Barnadas
authors.affiliation: Departamento de Astronomía y Meteorología, Universidad de Barcelona, Barcelona, España.
authors.forename: X
authors.initials: X
authors.lastname: de Cabo
authors.affiliation: Servicio de Dermatología, Hospital Germans Trías i Pujol de Badalona, Barcelona, España.
authors.forename: J M
authors.initials: JM
authors.lastname: Carrrascosa
authors.affiliation: Unidad de Fotobiología Dermatológica y Oncología Cutánea, Departamento de Dermatología y Medicina, Universidad de Málaga, Málaga, España.
authors.forename: M V
authors.initials: MV
authors.lastname: de Gálvez Aranda
authors.affiliation: Servicio de Dermatología, Hospital Universitario Cruces, Baracaldo, España.
authors.forename: J
authors.initials: J
authors.lastname: Gardeazábal
authors.affiliation: Servicio de Dermatología, Hospital del Mar, Barcelona, España.
authors.forename: A
authors.initials: A
authors.lastname: Giménez-Arnau
authors.affiliation: Servicio de Dermatología, Hospital Clínic de Barcelona, Barcelona, España.
authors.forename: M
authors.initials: M
authors.lastname: Lecha
authors.affiliation: Departamento de Astronomía y Meteorología, Universidad de Barcelona, Barcelona, España.
authors.forename: J
authors.initials: J
authors.lastname: Lorente
authors.affiliation: Grupo de Radiación Solar, Universidad de Valencia, Valencia, España.
authors.forename: J A
authors.initials: JA
authors.lastname: Martínez-Lozano
authors.affiliation: Facultad de Medicina, Complejo Hospital Universitario, Santiago de Compostela, España.
authors.forename: M T
authors.initials: MT
authors.lastname: Rodríguez Granados
authors.affiliation: Departamento de Astronomía y Meteorología, Universidad de Barcelona, Barcelona, España.
authors.forename: Y
authors.initials: Y
authors.lastname: Sola
authors.affiliation: Grupo de Radiación Solar, Universidad de Valencia, Valencia, España.
authors.forename: M P
authors.initials: MP
authors.lastname: Utrillas
mesh_terms: D000328:Adult; D000368:Aged; D015331:Cohort Studies; D004890:Erythema / Q000145:classification* / Q000209:etiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012867:Skin / Q000528:radiation effects*; D012882:Skin Tests; D013472:Sunlight; D014466:Ultraviolet Rays; D055815:Young Adult
keywords: Broadband ultraviolet-B lamps; Dosis eritemática mínima; Fotodermatosis; Fototest; Lámparas de luz ultravioleta B de banda ancha; Minimal erythema dose; Photodermatosis; Phototesting; Simulador solar; Solar simulator