title: Histopathology and immune histochemistry of red tattoo reactions. Interface dermatitis is the lead pathology, with increase in T-lymphocytes and Langerhans cells suggesting an allergic pathomechanism.
abstract: BACKGROUND
  The majority of tattoo reactions are affiliated to red pigmented areas and often suspected to be allergic in nature. A sizeable series of biopsies of such reactions has not previously been performed. The aim of this study was to type and grade epidermal and dermal changes in tattoo reactions to red/red nuances by microscopy and immunochemistry relevant for the assessment of a possible allergic pathomechanism.
  
  
  METHODS
  Skin biopsies were taken from red tattoo reactions, graded by conventional microscopy and stained for T and B-lymphocytes, Langerhans cells, macrophages and tumour necrosis factor (TNF)-α.
  
  
  RESULTS
  The study included 19 biopsies from 19 patients. The culprit colours were red/pink (n = 15) and purple/bordeaux (n = 4). Interface dermatitis was clearly the lead pathology found in 78% of samples, overlapped with granulomatous (in 32%) and pseudolymphomatous reaction patterns (in 32%). Epidermal hyperkeratosis (in 89%) was common as was leakage of red pigment across the dermo-epidermal junction, with transepidermal elimination (in 28%). The dermal cellular infiltration was dominated by T-lymphocytes (in 100%), Langerhans cells (in 95%) and macrophages (in 100%). TNF-α was common.
  
  
  CONCLUSIONS
  The predominant histological pattern of chronic tattoo reactions in red/red nuances is interface dermatitis. T-lymphocytes and Langerhans cells are increased suggesting an allergic pathomechanism. TNF-α may contribute to reactions. In many cases, overlapping reactive patterns were identified.
authors.affiliation: Department of Dermatology, Bispebjerg University Hospital, Copenhagen NV, Denmark.
authors.forename: T
authors.initials: T
authors.lastname: Høgsberg
authors.affiliation: Department of Pathology, Bispebjerg University Hospital, Copenhagen NV, Denmark.
authors.forename: B M
authors.initials: BM
authors.lastname: Thomsen
authors.affiliation: Department of Dermatology, Bispebjerg University Hospital, Copenhagen NV, Denmark.
authors.forename: J
authors.initials: J
authors.lastname: Serup
mesh_terms: D000293:Adolescent; D000328:Adult; D003116:Color; D004396:Coloring Agents / Q000506:poisoning*; D016207:Cytokines / Q000276:immunology; D017449:Dermatitis, Allergic Contact / Q000209:etiology / Q000276:immunology* / Q000473:pathology*; D005260:Female; D006801:Humans; D007801:Langerhans Cells / Q000276:immunology* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D012867:Skin / Q000187:drug effects / Q000276:immunology / Q000473:pathology; D013601:T-Lymphocytes / Q000276:immunology* / Q000473:pathology; D013653:Tattooing / Q000009:adverse effects*; D055815:Young Adult
chemical_list: D004396:Coloring Agents; D016207:Cytokines
keywords: Langerhans cells; T-lymphocytes; allergy; interface dermatitis; tattoo