title: Reflectance confocal microscopy may differentiate acute allergic and irritant contact dermatitis in vivo.
abstract: BACKGROUND
  Acute irritant contact dermatitis (ICD) and allergic contact dermatitis (ACD) may be difficult to distinguish by clinical or histologic assessment. Reflectance confocal microscopy (RCM) enables real-time, high-resolution skin imaging in vivo.
  
  
  OBJECTIVE
  We sought to image, characterize, and distinguish acute ACD and ICD in vivo.
  
  
  METHODS
  Volunteers with ACD were patch tested with an allergen and the irritant, sodium lauryl sulfate. RCM imaging and transepidermal water loss measurements were performed at 24 and 72 hours. Biopsy specimens were correlated with RCM images.
  
  
  RESULTS
  Spongiosis, epidermal inflammatory cell infiltrate, and vesicle formation were observed in ACD and ICD. Compared with ACD, ICD showed greater disruption of the stratum corneum, and more parakeratosis. There was a significantly greater increase in transepidermal water loss for ICD compared with ACD.
  
  
  CONCLUSIONS
  RCM is a promising tool for dynamic, noninvasive assessment and may help to differentiate acute ACD and sodium lauryl sulfate-induced ICD.
authors.affiliation: Wellman Laboratories of Photomedicine, Massachusetts Geneeral Hospital, Harvard Medical School, Boston, Massachusetts 02114, USA.
authors.forename: Kirsty
authors.initials: K
authors.lastname: Swindells
authors.forename: Nadine
authors.initials: N
authors.lastname: Burnett
authors.forename: Francisca
authors.initials: F
authors.lastname: Rius-Diaz
authors.forename: Ernesto
authors.initials: E
authors.lastname: González
authors.forename: Martin C
authors.initials: MC
authors.lastname: Mihm
authors.forename: Salvador
authors.initials: S
authors.lastname: González
mesh_terms: D000328:Adult; D000368:Aged; D001706:Biopsy; D017449:Dermatitis, Allergic Contact / Q000175:diagnosis* / Q000473:pathology; D017453:Dermatitis, Irritant / Q000175:diagnosis* / Q000473:pathology; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008297:Male; D018613:Microscopy, Confocal / Q000379:methods; D008875:Middle Aged; D012680:Sensitivity and Specificity; D012882:Skin Tests