title: Challenge testing in children with allergy to cow's milk proteins.
abstract: OBJECTIVE
  To evaluate clinical response after challenge testing in infants with allergy to cow's milk proteins at diagnosis and again when these infants were aged 1 year old and had been fed an exclusion diet.
  
  
  METHODS
  We performed a prospective study of 49 infants aged less than 6 months with a clinical history suggestive of cow's milk protein allergy, positive skin prick test and specific IgE for alpha-lactalbumin, beta-lactoglobulin and casein. In all children challenge test with cow-milk adapted formula was carried out at diagnosis. The same procedures were repeated when the children were aged 1 year but challenge testing was repeated only in children with a negative skin prick test and specific IgE antibodies to cow's milk proteins.
  
  
  RESULTS
  At diagnosis, challenge tests produced immediate hypersensitivity reactions in 94% of infants. Late reactivity (i.e., more than 2 hours after challenge) was found in only 6% of infants, all of whom presented dyspepsia. When the infants were aged 1 year, and after results of immunological study were negative, a further challenge test was performed in 24 (49%) of lactating infants included in the study. Of these 24 infants, positive challenge was found in 5 (21%). None of the infants presented immediate symptomatology (clinical features appeared 7 days after the reintroduction of cow's milk proteins).
  
  
  CONCLUSIONS
  Ninety-four percent of challenge tests performed at diagnosis provoked immediate reactions. The results of challenge tests after a negative skin prick test in children with normal concentrations of specific IgE were positive in 21% infants, who presented late reactivity (a mean of 7 days after milk ingestion).
authors: Department of Allergy and Clinical Immunology, Integrated Unit Hospital Sant Joan de Déu, University of Barcelona, Spain.
authors: A M
authors: AM
authors: Plaza Martín
authors: M A
authors: MA
authors: Martín Mateos
authors: M T
authors: MT
authors: Giner Muñoz
authors: J I
authors: JI
authors: Sierra Martínez
mesh_terms: D000485:Allergens / Q000009:adverse effects; D000818:Animals; D000918:Antibody Specificity; D002364:Caseins / Q000276:immunology; D002417:Cattle; D005260:Female; D006801:Humans; D006968:Hypersensitivity, Delayed / Q000209:etiology; D006969:Hypersensitivity, Immediate / Q000209:etiology; D007022:Hypotension / Q000209:etiology; D007073:Immunoglobulin E / Q000097:blood / Q000276:immunology; D007223:Infant; D007768:Lactalbumin / Q000276:immunology; D007782:Lactoglobulins / Q000276:immunology; D008297:Male; D016269:Milk Hypersensitivity / Q000175:diagnosis* / Q000276:immunology; D008894:Milk Proteins / Q000009:adverse effects; D012130:Respiratory Hypersensitivity / Q000209:etiology; D012882:Skin Tests; D014839:Vomiting / Q000209:etiology
chemical_list: D000485:Allergens; D002364:Caseins; D007782:Lactoglobulins; D008894:Milk Proteins; D007073:Immunoglobulin E; D007768:Lactalbumin