title: The ABC of Hidradenitis Suppurativa: A Validated Glossary on how to Name Lesions.
abstract: BACKGROUND
  The precise clinical description of skin lesions observed in some patients with hidradenitis suppurativa (HS) can be extremely difficult.
  
  
  OBJECTIVE
  Establishing a validated glossary of terms allowing the best possible description of lesions observed in HS patients.
  
  
  METHODS
  Five international experts of HS were to assess a series of 25 photos representing typical lesions of this disorder. For each photo, the experts were asked whether naming of the lesions was possible or not and, if yes, by using which noun. Agreement of their responses was calculated using Fleiss's kappa index. Using a Delphi strategy, photos with disagreement were discussed, and photos were reevaluated on the next day. In case of agreement on the impossibility of naming some clinical situations, new terms, to be included into the glossary, were agreed upon.
  
  
  RESULTS
  After the first round of photos, agreement between the experts was poor with a kappa index of only 0.33 (95% CI 0.22-0.46). After extensive discussion of cases with disagreement, the kappa index increased on day 2 to 0.75 (95% CI 0.60-0.87), allowing to conclude on good interobserver agreement on terminology. Furthermore, a few clinical situations were identified in which naming with established semantics is so far not possible. For these situations, the terms 'multicord', 'multipore', 'multitunnel' and 'retraction' were defined.
  
  
  CONCLUSIONS
  This is the first validation of clinical terms used to describe lesions in patients with HS. This should be helpful in better defining the clinical phenotypes observed in this disorder.
authors.affiliation: Facultx00E9; de Mx00E9;decine, Universitx00E9; de Strasbourg, Strasbourg, France.
authors.forename: Dan
authors.initials: D
authors.lastname: Lipsker
authors.forename: François
authors.initials: F
authors.lastname: Severac
authors.forename: Marie
authors.initials: M
authors.lastname: Freysz
authors.forename: Eric
authors.initials: E
authors.lastname: Sauleau
authors.forename: Jurr
authors.initials: J
authors.lastname: Boer
authors.forename: Lennart
authors.initials: L
authors.lastname: Emtestam
authors.forename: Łukasz
authors.initials: Ł
authors.lastname: Matusiak
authors.forename: Errol
authors.initials: E
authors.lastname: Prens
authors.forename: Charles
authors.initials: C
authors.lastname: Velter
authors.forename: Cédric
authors.initials: C
authors.lastname: Lenormand
authors.forename: Nicolas
authors.initials: N
authors.lastname: Meyer
authors.forename: Gregor B E
authors.initials: GB
authors.lastname: Jemec
mesh_terms: D017497:Hidradenitis Suppurativa / Q000473:pathology*; D006801:Humans; D009626:Terminology as Topic