title: A histopathologic study of mechanic's hands associated with dermatomyositis: a report of five cases.
abstract: BACKGROUND
  Mechanic's hand is a defined specific skin eruption associated with dermatomyositis; there are few reports concerning its histopathology. As mechanic's hand clinically resembles hand eczema, it is important to distinguish between these two conditions.
  
  
  OBJECTIVE
  To determine the characteristic clinical and histopathologic features of mechanic's hand, and to clarify whether these two conditions can be differentiated by histopathologic findings.
  
  
  METHODS
  We analyzed clinicopathologically five patients with mechanic's hands who visited our clinic between 2006 and 2007.
  
  
  RESULTS
  The clinical features of mechanic's hands were discrete hyperkeratotic erythema on the ulnar aspect of the thumbs and the radial aspect of the fingers. In all five cases, the histologic findings included marked hyperkeratosis, focal parakeratosis, psoriasiform acanthosis, and colloid bodies in the epidermis. There were mononuclear cell infiltrates around the blood vessels, and mucin deposition was observed in the dermis.
  
  
  CONCLUSIONS
  The histopathologic findings of mechanic's hands are specific and different from those of eczema. A histopathologic examination is useful for the diagnosis of mechanic's hands associated with dermatomyositis and a high incidence of interstitial pneumonia.
authors.affiliation: Department of Dermatology and Section of Allergy and Rheumatology, St. Luke's International Hospital, Tokyo, Japan. miisumi@med.kitasato-u.ac.jp
authors.forename: Sumiyuki
authors.initials: S
authors.lastname: Mii
authors.forename: Ritsuko
authors.initials: R
authors.lastname: Kobayashi
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Nakano
authors.forename: Harumi
authors.initials: H
authors.lastname: Harada
authors.forename: Masato
authors.initials: M
authors.lastname: Okada
authors.forename: Yukio
authors.initials: Y
authors.lastname: Matsui
authors.forename: Takao
authors.initials: T
authors.lastname: Fujii
authors.forename: Hikaru
authors.initials: H
authors.lastname: Eto
mesh_terms: D000305:Adrenal Cortex Hormones / Q000627:therapeutic use; D000328:Adult; D000368:Aged; D000974:Antibodies, Antinuclear / Q000097:blood; D001706:Biopsy; D001943:Breast Neoplasms / Q000150:complications; D003882:Dermatomyositis / Q000150:complications / Q000188:drug therapy / Q000473:pathology*; D005260:Female; D006229:Hand Dermatoses / Q000150:complications / Q000188:drug therapy / Q000473:pathology*; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000473:pathology; D008025:Ligases / Q000276:immunology; D017563:Lung Diseases, Interstitial / Q000150:complications; D008297:Male; D008875:Middle Aged; D009220:Myositis / Q000150:complications
chemical_list: D000305:Adrenal Cortex Hormones; D000974:Antibodies, Antinuclear; D008025:Ligases