title: In vivo and in vitro studies on the residual allergenicity of partially hydrolysed infant formulae.
abstract: OBJECTIVE
  Because allergen-reduced formulae are widely used in the prevention and treatment of cow's milk allergy in children and because anaphylactic reactions have been reported for some hydrolysed formulae, it is of clinical relevance to know about the residual allergenicity of so-called hypoallergenic formulae.
  
  
  METHODS
  We therefore studied the reactions of 20 children (mean age 1.6 years) with proven cow's milk allergy to a variety of formulae, using skin prick test, specific IgE in serum, protein content and RAST inhibition.
  
  
  RESULTS
  Whereas all but two children with a clinically relevant cow's milk allergy had a positive skin prick test to cow's milk, some children still showed positive responses to the partially hydrolysed formulae. No child had a positive skin test to the amino acid formula. Specific IgE to the partially hydrolysed whey formula (median 0.28 U/ml) was significantly lower (p < 0.003) than to cow's milk. Specific IgE to the partially hydrolysed whey/casein formula, soy/pork collagen hydrolysate and the amino acid formula was in a low range (median values 0.19, 0.23 and 0.21 U/ml, respectively). While determination of the protein content of the formulae gave no valid information, RAST/EAST inhibition was highest for cow's milk, followed by the partially hydrolysed whey formula, partially hydrolysed whey/casein formula, soy/pork collagen formula, and the amino acid formula.
  
  
  CONCLUSIONS
  Skin prick test and RAST inhibition test are suitable methods for determining the residual allergenicity of hydrolysed infant formulae, while determination of protein content using the applied modified Lowry method is not helpful.
authors.affiliation: University Children's Hospital Charité, Berlin, Germany.
authors.forename: B
authors.initials: B
authors.lastname: Niggemann
authors.forename: C
authors.initials: C
authors.lastname: Binder
authors.forename: U
authors.initials: U
authors.lastname: Klettke
authors.forename: U
authors.initials: U
authors.lastname: Wahn
mesh_terms: D000596:Amino Acids / Q000276:immunology; D000818:Animals; D002364:Caseins / Q000276:immunology; D002648:Child; D002675:Child, Preschool; D003094:Collagen / Q000276:immunology; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D006967:Hypersensitivity / Q000097:blood / Q000276:immunology*; D007073:Immunoglobulin E / Q000097:blood; D007223:Infant; D007225:Infant Food / Q000009:adverse effects*; D008297:Male; D016269:Milk Hypersensitivity / Q000097:blood / Q000178:diet therapy / Q000276:immunology*; D008894:Milk Proteins / Q000276:immunology; D011492:Protein Hydrolysates / Q000276:immunology* / Q000627:therapeutic use; D011852:Radioallergosorbent Test; D012882:Skin Tests; D013025:Glycine max / Q000276:immunology; D013552:Swine; D000067816:Whey Proteins
chemical_list: D000596:Amino Acids; D002364:Caseins; D008894:Milk Proteins; D011492:Protein Hydrolysates; D000067816:Whey Proteins; D007073:Immunoglobulin E; D003094:Collagen