title: Evaluation of the utility of atopy patch testing, skin prick testing, and total and specific IgE assays in the diagnosis of cow's milk allergy.
abstract: BACKGROUND
  Information on the utility of atopy patch testing (APT) in the diagnosis of food allergy is derived from studies of children with atopic dermatitis.
  
  
  OBJECTIVE
  To evaluate the usefulness of APT in the diagnosis of cow's milk allergy (CMA) and to determine interleukin 4 and interferon-gamma production by peripheral blood mononuclear cells.
  
  
  METHODS
  Thirty-seven children (median age, 11 months) with suspected CMA who had a variety of symptoms that involved many organ systems were evaluated using double-blind placebo-controlled food challenges (DBPCFCs), and the performances of milk specific IgE, skin prick testing (SPT), and APT were determined. To search for a possible relationship between the diagnostic tests and the TH1/TH2 immune response, we measured interferon-gamma and interleukin 4 levels in the supernatants of peripheral blood mononuclear cell cultures.
  
  
  RESULTS
  Seventeen children with positive DBPCFC results and 6 with a history of anaphylaxis were diagnosed as having CMA. The combined use of APT and SPT had a sensitivity of 100% and a negative predictive value of 100% but a specificity of 50% and a positive predictive value of 76%. The addition of milk specific IgE assays to APT and SPT did not improve these values. Pattern of cytokine secretion was not associated with APT positivity or a specific response to DBPCFC.
  
  
  CONCLUSIONS
  Atopy patch testing may be a useful adjunct to SPT in excluding CMA in children who have allergic manifestations other than atopic dermatitis. However, DBPCFCs are still necessary in the presence of positive test results.
authors.affiliation: Pediatric Allergy and Asthma Unit, Hacettepe University School of Medicine and Ihsan Dogramaci Children's Hospital, Hacettepe, Ankara, Turkey.
authors.forename: Ozlem
authors.initials: O
authors.lastname: Keskin
authors.forename: Ayfer
authors.initials: A
authors.lastname: Tuncer
authors.forename: Gonul
authors.initials: G
authors.lastname: Adalioglu
authors.forename: Bulent E
authors.initials: BE
authors.lastname: Sekerel
authors.forename: Cansin
authors.initials: C
authors.lastname: Sackesen
authors.forename: Omer
authors.initials: O
authors.lastname: Kalayci
mesh_terms: D000818:Animals; D000918:Antibody Specificity; D002648:Child; D002675:Child, Preschool; D004311:Double-Blind Method; D005069:Evaluation Studies as Topic; D005260:Female; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood*; D007223:Infant; D007371:Interferon-gamma / Q000097:blood; D015847:Interleukin-4 / Q000097:blood; D008297:Male; D008892:Milk / Q000009:adverse effects*; D016269:Milk Hypersensitivity / Q000097:blood / Q000175:diagnosis* / Q000209:etiology; D009000:Monocytes / Q000276:immunology; D010328:Patch Tests; D012882:Skin Tests
chemical_list: D015847:Interleukin-4; D007073:Immunoglobulin E; D007371:Interferon-gamma