title: Acral pseudolymphomatous angiokeratoma of children: immunohistochemical and clonal analyses of the infiltrating cells.
abstract: BACKGROUND
  Acral pseudolymphomatous angiokeratoma of children (APACHE) is a disorder characterized clinically by red nodules and histopathologically by a massive subepidermal lymphohistiocytic infiltrate. Although it was initially thought to be a vascular nevus, it has never been regarded as a pseudolymphoma.
  
  
  METHODS
  We report a 7-year-old-girl with small red nodules on the dorsum of the right foot and a 73-year-old man with asymptomatic brown-red nodules on the lower extremities.
  
  
  RESULTS
  Histopathologic examination revealed a massive lymphohistiocytic infiltrate with plasma cells, some eosinophils, or a multinucleated giant cell immediately beneath the epidermis. Thick-walled vessels were observed in the infiltrate. These characteristics are identical to those of acral pseudolymphomatous angiokeratoma of children. The infiltrate was composed mainly of equal numbers of CD4+ or CD8+ T cells and equal numbers of B cells stained for kappa or lambda light chains. PCR amplification of rearranged immunoglobulin heavy chain genes or T-cell receptor gamma genes showed no evidence of clonality, suggesting that these infiltrates were polyclonal both for B and T cells.
  
  
  CONCLUSIONS
  Our data support the idea that this disorder represents a reactive process. The modified term 'papular angiolymphoid hyperplasia' would define this disorder more appropriately.
authors.affiliation: Department of Dermatology, Faculty of Medicine, Tottori University, Yonago, Japan. yohagari@grape.med.tottori-u.ac.jp
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Hagari
authors.forename: Shinobu
authors.initials: S
authors.lastname: Hagari
authors.forename: Naoto
authors.initials: N
authors.lastname: Kambe
authors.forename: Toshio
authors.initials: T
authors.lastname: Kawaguchi
authors.forename: Shu
authors.initials: S
authors.lastname: Nakamoto
authors.forename: Motoyuki
authors.initials: M
authors.lastname: Mihara
mesh_terms: D000368:Aged; D000794:Angiokeratoma / Q000235:genetics* / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D015703:Antigens, CD / Q000378:metabolism; D002648:Child; D002999:Clone Cells / Q000378:metabolism; D005260:Female; D005803:Genes, Immunoglobulin / Q000235:genetics; D019675:Genes, T-Cell Receptor gamma; D006801:Humans; D007143:Immunoglobulin Heavy Chains / Q000235:genetics; D007147:Immunoglobulin Light Chains / Q000378:metabolism; D007150:Immunohistochemistry; D008297:Male; D016133:Polymerase Chain Reaction; D019310:Pseudolymphoma / Q000235:genetics* / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D012878:Skin Neoplasms / Q000235:genetics* / Q000276:immunology / Q000378:metabolism* / Q000473:pathology
chemical_list: D015703:Antigens, CD; D007143:Immunoglobulin Heavy Chains; D007147:Immunoglobulin Light Chains