title: Keratolysis exfoliativa (dyshidrosis lamellosa sicca): a distinct peeling entity.
abstract: BACKGROUND
  Keratolysis exfoliativa (KE), also known as dyshidrosis lamellosa sicca, is a palmoplantar dermatosis characterized by air-filled blisters and collarette desquamation. It has been regarded as a subtype of dyshidrotic eczema, a fungal infection or a dermatophytid reaction. KE may also resemble acral peeling skin syndrome and localized epidermolysis bullosa simplex. Although KE is a common disorder, it is a rarely reported and is an under-recognized dermatosis.
  
  
  OBJECTIVE
  To delineate the characteristic features of KE.
  
  
  METHODS
  We investigated the clinical, immunohistopathological, ultrastructural and molecular features of KE. Patients were included from the clinical records. Additional diagnostic research consisted of mutation analysis of the candidate genes TGM5, KRT5, KRT14, FLG, SPINK6 and SPINK9.
  
  
  RESULTS
  A total of 24 patients with KE were identified, six with familial and 18 with sporadic KE. Lesions consisted of air-filled blisters only on palmoplantar skin, followed by collarette and lamellar peeling. Both light microscopy and electron microscopy showed cleavage and partially degraded corneodesmosomes within the stratum corneum, whereas immunofluorescence microscopy showed normal expression of corneodesmosomal components. No mutations were found in TGM5, KRT5/14 and SPINK6/9. There was no clear link with atopy or with FLG mutations.
  
  
  CONCLUSIONS
  Our study suggests premature corneodesmolysis as the main pathological mechanism of this palmoplantar skin disorder. We conclude that KE appears to be a distinct peeling entity.
authors.affiliation: Centre for Blistering Diseases, Department of Dermatology, University of Groningen, University Medical Centre Groningen, Hanzeplein 1, 9700 RB Groningen, the Netherlands.
authors.forename: Y Y
authors.initials: YY
authors.lastname: Chang
authors.forename: J
authors.initials: J
authors.lastname: van der Velden
authors.forename: G
authors.initials: G
authors.lastname: van der Wier
authors.forename: D
authors.initials: D
authors.lastname: Kramer
authors.forename: G F H
authors.initials: GF
authors.lastname: Diercks
authors.forename: M
authors.initials: M
authors.lastname: van Geel
authors.forename: P J
authors.initials: PJ
authors.lastname: Coenraads
authors.forename: P L J M
authors.initials: PL
authors.lastname: Zeeuwen
authors.forename: M F
authors.initials: MF
authors.lastname: Jonkman
mesh_terms: D000293:Adolescent; D000328:Adult; D015415:Biomarkers / Q000378:metabolism; D002648:Child; D004252:DNA Mutational Analysis; D003873:Dermatitis, Exfoliative / Q000175:diagnosis* / Q000235:genetics; D003937:Diagnosis, Differential; D005260:Female; D000091344:Filaggrin Proteins; D005455:Fluorescent Antibody Technique; D006801:Humans; D007633:Keratins / Q000235:genetics; D008297:Male; D008854:Microscopy, Electron; D008875:Middle Aged; D009426:Netherlands; D010375:Pedigree; D012867:Skin / Q000648:ultrastructure; D012873:Skin Diseases, Genetic / Q000175:diagnosis* / Q000235:genetics; D011795:Surveys and Questionnaires
chemical_list: D015415:Biomarkers; C000717249:FLG protein, human; D000091344:Filaggrin Proteins; D007633:Keratins