title: A 20-year analysis of previous and emerging allergens that elicit photoallergic contact dermatitis.
abstract: BACKGROUND
  Retrospective chart reviews are periodically needed to update allergen series to detect changes in photoallergic contact dermatitis (PACD) over time.
  
  
  OBJECTIVE
  We sought to evaluate photopatch test results during a 13-year period and extend the observations to 20 years.
  
  
  METHODS
  A retrospective chart review was conducted in patients who were photopatch tested.
  
  
  RESULTS
  In all, 76 patients were evaluated. A total of 69 positive photopatch and 45 positive patch test reactions were detected in 30 and 23 patients, respectively. The frequencies of the positive photopatch test reactions were sunscreens 23.2%, antimicrobial agents 23.2%, medications 20.3%, fragrances 13%, plants and plant derivatives 11.6%, and pesticides 8.7%. Of the positive photopatch reactions to antimicrobial agents, 60% were caused by Fentichlor.
  
  
  CONCLUSIONS
  This study was a retrospective chart analysis, and the number of patients was small.
  
  
  CONCLUSIONS
  Sunscreens and antimicrobial agents were the most frequent allergens eliciting PACD, and there was a decrease in PACD caused by fragrances. The number of reactions to medications increased. This study also demonstrated that pesticides can be a cause of PACD. The detection of reactions to Fentichlor was unexpected and, although they have been attributed in some studies to cross-reactions to sulfanilamides and bithionol, such a robust association was not observed in this study. This study extends our experience of the changes in the allergens that elicit PACD to 20 years.
authors.affiliation: Charles C. Harris Skin and Cancer Pavilion, Ronald O. Perelman Department of Dermatology, New York University School of Medicine, New York, New York 10016, USA.
authors.forename: Frank C
authors.initials: FC
authors.lastname: Victor
authors.forename: David E
authors.initials: DE
authors.lastname: Cohen
authors.forename: Nicholas A
authors.initials: NA
authors.lastname: Soter
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000485:Allergens / Q000009:adverse effects*; D002648:Child; D017454:Dermatitis, Photoallergic / Q000453:epidemiology / Q000276:immunology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D013997:Time Factors; D055815:Young Adult
chemical_list: D000485:Allergens