title: Antinuclear antibodies in atopic dermatitis: a cross-sectional study on 346 children.
abstract: BACKGROUND
  Atopic dermatitis (AD) is a chronic inflammatory skin disease that can be classified into an extrinsic or intrinsic type. A high percentage of patients, especially adults with the extrinsic type of AD, have been reported to show antibodies to antinuclear proteins (ANA). We aimed to study the prevalence of ANA in children with AD and to evaluate clinical differences between patients with ANA-positive and ANA-negative AD.
  
  
  METHODS
  A total 346 serum samples from children with active AD (mean age 5.8 years) and 117 hospital controls without known skin, inflammatory, or immune-mediated disease (mean age 7.9 years) were tested for IgG ANA with indirect immunofluorescence on HEp-2 cells, total serum IgE levels, and IgE type antibodies to food allergen panels.
  
  
  RESULTS
  In total, 47 patients with AD (13.6%) and 15 subjects in the control group (12.8%) were ANA positive at screening dilution 1:10 (P > 0.05). In patients with AD, ANA was found already at the age of 2 years, significantly more often in females (P < 0.005) and at slightly higher titers (up to 1:160). No differences were found in ANA positivity regarding the severity of AD or sensitization to food allergens.
  
  
  CONCLUSIONS
  No significant differences were observed between AD and the control group, or between different subtypes of AD in ANA prevalence. In both groups, ANA frequency increased with age, but in patients with AD, ANA had a tendency to appear earlier. Therefore, active AD during the early years of life could dispose selected patients towards earlier development of systemic autoreactivity and stress the need for regular follow-up of patients with ANA-positive AD.
authors.affiliation: Department of Immunology, Institute of Bio- and Translational Medicine and Centre of Excellence for Translational Medicine, University of Tartu, Tartu, Estonia.
authors.forename: Krista
authors.initials: K
authors.lastname: Ress
authors.forename: Kaja
authors.initials: K
authors.lastname: Metsküla
authors.forename: Triine
authors.initials: T
authors.lastname: Annus
authors.forename: Urve
authors.initials: U
authors.lastname: Putnik
authors.forename: Kristi
authors.initials: K
authors.lastname: Lepik
authors.forename: Katrin
authors.initials: K
authors.lastname: Luts
authors.forename: Oivi
authors.initials: O
authors.lastname: Uibo
authors.forename: Raivo
authors.initials: R
authors.lastname: Uibo
mesh_terms: D000293:Adolescent; D000367:Age Factors; D000974:Antibodies, Antinuclear / Q000097:blood*; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D003876:Dermatitis, Atopic / Q000276:immunology*; D005260:Female; D005512:Food Hypersensitivity / Q000276:immunology; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood*; D007074:Immunoglobulin G / Q000097:blood*; D007223:Infant; D008297:Male; D012720:Severity of Illness Index; D012737:Sex Factors
chemical_list: D000974:Antibodies, Antinuclear; D007074:Immunoglobulin G; D007073:Immunoglobulin E