title: Contact sensitization to tree moss (Evernia furfuracea extract, INCI) is heterogeneous.
abstract: BACKGROUND
  Evernia prunastri (oak moss) and Evernia furfuracea (tree moss) are lichens from which natural extracts are obtained.
  
  
  OBJECTIVE
  To identify possible subgroups of E. furfuracea-sensitized patients according to whether these are allergic to lichen components or to contaminants.
  
  
  METHODS
  A retrospective analysis was performed of surveillance data collected by the Information Network of Departments of Dermatology (www.ivkd.org) in 2003-2010 with oak moss absolute (1% pet.), tree moss absolute (1% pet.), and colophonium (colophony, 20% pet.).
  
  
  RESULTS
  In total, 3030 patients had been tested with all three allergens. Positive reactions to E. furfuracea were observed in 6.37%, to E. prunastri in 5.71%, and to colophonium in 4.82%. Concordance between positive reactions to E. prunastri and E. furfuracea was good only in patients not co-sensitized to colophonium (Cohen's κ = 0.681, 95% confidence interval 0.615-0.746). Moreover, E. furfuracea-sensitized patients showed (strong or extreme) concomitant reactions to colophonium significantly more often if not co-sensitized to E. prunastri.
  
  
  CONCLUSIONS
  Two subgroups of E. furfuracea-sensitized patients are identifiable: (i) those with sensitization to (oxidized) resin acids, as indicated by positive patch test reactions also to colophonium, and (ii) those non-sensitized to resin acids, but sensitized to common constituents of E. prunastri and E. furfuracea.
authors.affiliation: Department of Medical Informatics, Biometry and Epidemiology, University of Erlangen/Nürnberg, D-91054 Erlangen, Germany. wolfgang.uter@imbe.med.uni-erlangen.de
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Uter
authors.forename: Erich
authors.initials: E
authors.lastname: Schmidt
authors.forename: Holger
authors.initials: H
authors.lastname: Lessmann
authors.forename: Axel
authors.initials: A
authors.lastname: Schnuch
mesh_terms: D000328:Adult; D000485:Allergens / Q000009:adverse effects; D017449:Dermatitis, Allergic Contact / Q000175:diagnosis*; D005260:Female; D006801:Humans; D008011:Lichens; D008297:Male; D008875:Middle Aged; D010328:Patch Tests; D010936:Plant Extracts / Q000009:adverse effects*; D012116:Resins, Plant / Q000009:adverse effects; D012189:Retrospective Studies
chemical_list: D000485:Allergens; D010936:Plant Extracts; D012116:Resins, Plant