title: Atopic dirty neck or acquired atopic hyperpigmentation? An epidemiological and clinical study from the National Skin Centre in Singapore.
abstract: BACKGROUND
  'Atopic dirty neck' is a poorly understood acquired hyperpigmentation in patients with atopic dermatitis (AD).
  
  
  OBJECTIVE
  To report a single-centre experience with synthesis of this entity's features.
  
  
  METHODS
  All patients with AD with dirty neck seen over a 5-month period at the National Skin Centre were invited to participate.
  
  
  RESULTS
  Out of 544 AD patients examined, 78 (14.3%) had acquired pigmentation of the neck. The majority had moderate-to-severe underlying eczema. Histopathology showed increased epidermal melanin and dermal melanophages, a thickened basement membrane and a dense superficial perivascular infiltrate.
  
  
  CONCLUSIONS
  Acquired atopic hyperpigmentation has a high prevalence, particularly in adolescent Asian males. Clinico-pathological correlation suggests it results from both frictional melanosis and post-inflammatory hyperpigmentation. The rippled appearance and the onset in adolescence are probably due to accentuation of the juxta-clavicular beaded lines. Optimal control of eczema may improve and potentially prevent the development, which is of importance considering the psychosocial impact of the condition.
authors.affiliation: Department of Dermatology, National Skin Centre, Singapore, Singapore.
authors.forename: Amélie C
authors.initials: AC
authors.lastname: Seghers
authors.forename: Joyce S S
authors.initials: JS
authors.lastname: Lee
authors.forename: Chuen Seng
authors.initials: CS
authors.lastname: Tan
authors.forename: Yun Pei
authors.initials: YP
authors.lastname: Koh
authors.forename: Madeline S L
authors.initials: MS
authors.lastname: Ho
authors.forename: Yen Loo
authors.initials: YL
authors.lastname: Lim
authors.forename: Yoke Chin
authors.initials: YC
authors.lastname: Giam
authors.forename: Mark B Y
authors.initials: MB
authors.lastname: Tang
mesh_terms: D000046:Academic Medical Centers; D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D001707:Biopsy, Needle; D002648:Child; D003430:Cross-Sectional Studies; D003876:Dermatitis, Atopic / Q000175:diagnosis / Q000453:epidemiology* / Q000473:pathology*; D003906:Developing Countries; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D017495:Hyperpigmentation / Q000175:diagnosis / Q000453:epidemiology* / Q000473:pathology*; D007150:Immunohistochemistry; D015994:Incidence; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009333:Neck; D018570:Risk Assessment; D012494:Sampling Studies; D017678:Sex Distribution; D012846:Singapore / Q000453:epidemiology; D055815:Young Adult