title: Clinical differences between atopic and atopiform dermatitis.
abstract: BACKGROUND
  Atopic dermatitis (AD) has been divided into the "extrinsic" and "intrinsic" type, in which "intrinsic AD" is characterized by the absence of allergen-specific IgE. Still, there is no consensus whether this "intrinsic type" of AD, which we denominate as atopiform dermatitis (AFD), is a distinct entity.
  
  
  OBJECTIVE
  A case-control study was performed to compare the clinical and diagnostic features of AD and AFD.
  
  
  METHODS
  Patients with a clinical diagnosis of AD were selected. Cases did not have demonstrable allergen-specific IgE. Matched control subjects were tested positive for allergen-specific IgE. Patients were evaluated for medical history, quality of life, disease severity, and Hanifin and Rajka, U.K. and Millennium diagnostic criteria.
  
  
  RESULTS
  Eight percent (n = 34) of the selected patients had, in fact, AFD. Female predominance, absence of atopic diseases, later onset of disease, and milder disease severity were observed in AFD. A history of atopy, recurrent conjunctivitis, palmar hyperlinearity, keratosis pilaris, pityriasis alba, and hand and/or food eczema were significantly less present in AFD. Dennie-Morgan fold was positively associated with AFD.
  
  
  CONCLUSIONS
  Not all patients with negative allergen-specific IgE participated and a relatively small number of AFD patients were studied.
  
  
  CONCLUSIONS
  In addition to the absence of allergen-specific IgE, our findings support that AFD is an entity distinct from AD. With a distinction shown between AFD and AD, patient groups will be better defined and more homogeneous. Implications of this distinction will be of importance for preventive and therapeutic advice; diagnostic processes; and for future research.
authors.affiliation: Department of Dermatology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands. e.e.brenninkmeijer@amc.uva.nl
authors.forename: Elian E A
authors.initials: EE
authors.lastname: Brenninkmeijer
authors.forename: Phyllis I
authors.initials: PI
authors.lastname: Spuls
authors.forename: Catharina M
authors.initials: CM
authors.lastname: Legierse
authors.forename: Robert
authors.initials: R
authors.lastname: Lindeboom
authors.forename: J Henk Sillevis
authors.initials: JH
authors.lastname: Smitt
authors.forename: Jan D
authors.initials: JD
authors.lastname: Bos
mesh_terms: D000293:Adolescent; D000328:Adult; D000485:Allergens / Q000276:immunology*; D016022:Case-Control Studies; D003876:Dermatitis, Atopic / Q000145:classification* / Q000175:diagnosis* / Q000276:immunology / Q000503:physiopathology; D003937:Diagnosis, Differential; D000939:Epitopes; D005260:Female; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood*; D008297:Male; D008499:Medical Records; D011788:Quality of Life; D012720:Severity of Illness Index
chemical_list: D000485:Allergens; D000939:Epitopes; D007073:Immunoglobulin E