title: The advantage of establishing homogeneous patient groups: is it worth isolating 'juvenile acne of the face'?
abstract: BACKGROUND
  Acne is a highly heterogeneous disorder with respect to its regional involvement, demographics, lesion types and response to treatment. Homogeneous patient groups must therefore be created before measuring the severity of acne and interpreting the results of therapeutic trials. The individualization of 'juvenile acne of the face' is a first step in this direction.
  
  
  METHODS
  Based on textbooks, major reviews of acne and a 'Medline' literature search, we identified four key points to delineate sub groups of acne patients.
  
  
  RESULTS
  'Juvenile acne of the face' is defined by four main clinical criteria: (1) age (from puberty to age 25 years), (2) site (face), (3) lesion type (polymorphous), (4) absence of a causal factor. Other subgroups of 'true' acne are listed with their distinctive characteristics. Non-acne follicular diseases (i.e. without sebum retention) are listed.
  
  
  CONCLUSIONS
  We chose 'juvenile acne of the face' to define the first homogeneous group of patients because it is the most frequent form of acne and the target of most acne drugs. It has a sufficiently uniform prognosis to devise a functional and reproducible severity rating scale with the aim of facilitating the evaluation and comparison of therapeutic methods.
  
  
  CONCLUSIONS
  The next step in our work will be to elaborate severity scales which are dedicated to a single type of acne.
authors.affiliation: Service de Dermatologie, Hôpital Henri-Mondor, Assistance Publique-Hôpitaux de Paris, Université Paris XII, Créteil, France. jean.revuz@hmn.aphp.fr
authors.forename: J
authors.initials: J
authors.lastname: Revuz
authors.forename: H
authors.initials: H
authors.lastname: Pawin
authors.forename: F
authors.initials: F
authors.lastname: Poli
authors.forename: M
authors.initials: M
authors.lastname: Faure
authors.forename: M
authors.initials: M
authors.lastname: Chivot
authors.forename: C
authors.initials: C
authors.lastname: Beylot
authors.forename: B
authors.initials: B
authors.lastname: Dréno
mesh_terms: D000152:Acne Vulgaris / Q000145:classification / Q000209:etiology / Q000503:physiopathology* / Q000628:therapy; D000293:Adolescent; D006801:Humans