title: Polysensitization in recurrent lip dermatitis.
abstract: BACKGROUND
  In allergic contact dermatitis (ACD), polysensitization consists of positive patch test reactions to three or more unrelated allergens.
  
  
  OBJECTIVE
  The purpose of this case report is to document a 27-year-old female with recurrent lip dermatitis, polysensitization, and reactions to a number of clinically relevant exposures.
  
  
  METHODS
  Patch testing results revealed positive reactions to tixocortol-21-pivalate (3+), lanolin (3+), neomycin (3+), nickel (1+), hydroxyethyl methylacrylate (3+), bacitracin (3+), and abitol (3+).
  
  
  RESULTS
  The patient had seven positive reactions, meeting the criteria for polysensitization. Of known clinical relevance, the patient had applied lanolin-containing lip balms and hydrocortisone- and bacitracin-containing products to the lips, all of which she was strongly reactive to on patch testing.
  
  
  CONCLUSIONS
  Polysensitization occurs when three or more unrelated allergens are positive on patch testing. This case highlights the importance of considering polysensitization in ACD as numerous allergens that were positive on patch testing were clinically relevant.
authors.affiliation: College of Medicine, University of Saskatchewan, Saskatoon, SKDivision of Dermatology, University of Ottawa, Ottawa, ON kmf874@mail.usask.ca.
authors.forename: Kathleen
authors.initials: K
authors.lastname: Fraser
authors.affiliation: College of Medicine, University of Saskatchewan, Saskatoon, SKDivision of Dermatology, University of Ottawa, Ottawa, ON.
authors.forename: Melanie
authors.initials: M
authors.lastname: Pratt
mesh_terms: D000328:Adult; D000900:Anti-Bacterial Agents / Q000009:adverse effects; D003358:Cosmetics / Q000009:adverse effects; D017449:Dermatitis, Allergic Contact / Q000209:etiology* / Q000276:immunology; D005260:Female; D006801:Humans; D008047:Lip Diseases / Q000209:etiology* / Q000276:immunology; D010328:Patch Tests
chemical_list: D000900:Anti-Bacterial Agents; D003358:Cosmetics