title: [Microscopic diagnosis of onychomycoses].
abstract: BACKGROUND
  The microbiological identification of onychomycosis may be uncertain as some fungi growing in culture from this material are not necessarily pathogen and invasive. Conversely, the negativity of a culture is not rare even when fungi are seen by microscopy.
  
  
  METHODS
  We compared the information brought by standard histological examination, immunohistochemistry and in vivo confocal microscopy.
  
  
  RESULTS
  The histological examination of nails is of importance in this pathology. We present a laboratory technique that proves to be easy and rapid. We report diagnostic criteria allowing the distinction between dermatophytes, yeasts and non-dermatophyte molds. The standard microscopic examination may further be improved by immunohistochemistry using some antibodies to fungi. In vivo confocal microscopy is a technique for the future. The dermatologist will be able to see fungi in the nail at the clinical examination, without any sampling or peculiar preparation.
  
  
  CONCLUSIONS
  The histological examination is a routine technique useful for defining the nature and localization of fungi in the nail plate. Immunohistochemistry applied to onychomycosis is an experimental approach bringing prominent informations about the identification of fungi. In vivo confocal microscopy is a door opened to the future.
authors.affiliation: Service de Dermatopathologie, CHU du Sart Tilman, Liège.
authors.forename: G E
authors.initials: GE
authors.lastname: Piérard
authors.forename: J E
authors.initials: JE
authors.lastname: Arrese
authors.forename: S
authors.initials: S
authors.lastname: Pierre
authors.forename: C
authors.initials: C
authors.lastname: Bertrand
authors.forename: P
authors.initials: P
authors.lastname: Corcuff
authors.forename: J L
authors.initials: JL
authors.lastname: Lévêque
authors.forename: C
authors.initials: C
authors.lastname: Piérard-Franchimont
mesh_terms: D003883:Arthrodermataceae / Q000302:isolation & purification; D005533:Foot Dermatoses / Q000175:diagnosis; D006229:Hand Dermatoses / Q000175:diagnosis; D016591:Histocytological Preparation Techniques; D006801:Humans; D007150:Immunohistochemistry; D008853:Microscopy / Q000379:methods; D014009:Onychomycosis / Q000175:diagnosis* / Q000382:microbiology; D015003:Yeasts / Q000302:isolation & purification
vernacular_title: Diagnostic microscopique des onychomycoses.