title: Acrodermatitis chronic atrophicans: a chronic T-cell-mediated immune reaction against Borrelia burgdorferi? Clinical, histologic, and immunohistochemical study of five cases.
abstract: BACKGROUND
  Acrodermatitis chronica atrophicans (ACA) is a late manifestation of infection caused by Borrelia burgdorferi.
  
  
  OBJECTIVE
  Our purpose was to study the clinical, histopathologic, and immunohistochemical findings in patients with ACA to understand better the pathogenesis of the disease.
  
  
  METHODS
  Five patients were studied. Skin biopsy specimens were obtained from active lesions for histologic and immunohistochemical studies.
  
  
  RESULTS
  Clinical lesions included an initial erythematous discoloration in one patient and violaceous infiltrated plaques and nodules in four patients, three of whom also had late atrophic lesions. Biopsy specimens showed a dermal perivascular and interstitial lymphocytic infiltrate with plasma cells. There was a predominance of CD3+, CD4+ T cells in the dermal infiltrate. B cells were present in three patients. The dermal infiltrate showed an intense expression of lymphocyte function-associated antigen. The intercellular adhesion molecule type 1 was expressed on endothelial cells, perivascular mononuclear cells, and focally on basal keratinocytes.
  
  
  CONCLUSIONS
  Our findings suggest that a chronic, T-cell-mediated immune reaction against B. burgdorferi is involved in the pathogenesis of ACA.
authors.affiliation: Department of Dermatology, University of Basel, Switzerland.
authors.forename: S A
authors.initials: SA
authors.lastname: Buechner
authors.forename: T
authors.initials: T
authors.lastname: Rufli
authors.forename: P
authors.initials: P
authors.lastname: Erb
mesh_terms: D000169:Acrodermatitis / Q000276:immunology* / Q000382:microbiology / Q000473:pathology; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000907:Antibodies, Bacterial / Q000032:analysis; D015703:Antigens, CD / Q000032:analysis; D001284:Atrophy; D015748:Borrelia burgdorferi Group / Q000276:immunology*; D015815:Cell Adhesion Molecules / Q000032:analysis; D002908:Chronic Disease; D005260:Female; D006684:HLA-DR Antigens / Q000032:analysis; D006801:Humans; D007111:Immunity, Cellular; D007150:Immunohistochemistry; D018799:Intercellular Adhesion Molecule-1; D015603:Keratinocytes / Q000276:immunology; D007801:Langerhans Cells / Q000276:immunology; D008193:Lyme Disease / Q000150:complications; D008297:Male; D008875:Middle Aged; D012867:Skin / Q000276:immunology / Q000473:pathology; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D000907:Antibodies, Bacterial; D015703:Antigens, CD; D015815:Cell Adhesion Molecules; D006684:HLA-DR Antigens; D018799:Intercellular Adhesion Molecule-1