title: Vaccination-induced cutaneous pseudolymphoma.
abstract: BACKGROUND
  Although mild early cutaneous transient reactions to vaccinations are common, late-onset chronic lesions have been scarcely reported. We report herein a series of 9 patients presenting with cutaneous and subcutaneous pseudolymphoma.
  
  
  METHODS
  Nine patients presenting with late-onset, chronic skin lesions occurring at the site of antihepatitis B (8 cases) and antihepatitis A (one case) vaccination were reported. Histopathologic and immunohistochemic studies, and molecular analysis of clonality of skin biopsy specimens, were performed. Furthermore, the presence of vaccine products was investigated in skin lesions by using histochemical, microanalytic, and electronic microscopy techniques.
  
  
  RESULTS
  Histopathologic studies showed dermal and hypodermal lymphocytic follicular infiltrates with germinal center formation. The center of follicles was mostly composed of B cells without atypia, whereas CD4+ T cells were predominant at the periphery. Molecular analysis of clonality revealed a polyclonal pattern of B-cell and T-cell subsets. Aluminium deposits were evidenced in all cases by using histochemical staining in all cases, and by microanalysis and ultrastructural studies in one case. Associated manifestations were vitiligo (one case) and chronic fatigue with myalgia (two cases).
  
  
  CONCLUSIONS
  Cutaneous lymphoid hyperplasia is a potential adverse effect of vaccinations including aluminium hydroxide as an adjuvant. Further prospective studies are warranted to evaluate the incidence of this complication in the immunized population.
authors.affiliation: Institut de Recherche sur la Peau, Université Paris 7, Paris, France.
authors.forename: Eve
authors.initials: E
authors.lastname: Maubec
authors.forename: Laure
authors.initials: L
authors.lastname: Pinquier
authors.forename: Manuelle
authors.initials: M
authors.lastname: Viguier
authors.forename: Frédéric
authors.initials: F
authors.lastname: Caux
authors.forename: Emmanuelle
authors.initials: E
authors.lastname: Amsler
authors.forename: Sélim
authors.initials: S
authors.lastname: Aractingi
authors.forename: Hafid
authors.initials: H
authors.lastname: Chafi
authors.forename: Anne
authors.initials: A
authors.lastname: Janin
authors.forename: Jean-Michel
authors.initials: JM
authors.lastname: Cayuela
authors.forename: Louis
authors.initials: L
authors.lastname: Dubertret
authors.forename: François-Jérôme
authors.initials: FJ
authors.lastname: Authier
authors.forename: Hervé
authors.initials: H
authors.lastname: Bachelez
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D022362:Hepatitis A Vaccines / Q000009:adverse effects*; D017325:Hepatitis B Vaccines / Q000009:adverse effects*; D006801:Humans; D008297:Male; D008875:Middle Aged; D019310:Pseudolymphoma / Q000139:chemically induced* / Q000276:immunology / Q000473:pathology; D012871:Skin Diseases / Q000139:chemically induced* / Q000276:immunology / Q000473:pathology
chemical_list: D022362:Hepatitis A Vaccines; D017325:Hepatitis B Vaccines