title: Anaphylaxis to cow's milk formula containing short-chain galacto-oligosaccharide.
abstract: BACKGROUND
  On the basis of the proven prebiotic effects of oligosaccharides in cow's milk formula (CMF) in infants, CMFs are supplemented with oligosaccharides.
  
  
  OBJECTIVE
  We present a series of 5 cases of cow's milk-tolerant but atopic patients with a history of respiratory allergies. All had anaphylaxis after the ingestion of CMF supplemented with short-chain galacto-oligosaccharide (scGOS). The allergen trigger was investigated.
  
  
  METHODS
  Clinical histories were collated. Skin prick tests (SPTs) and basophil activation tests (BATs) were carried out with the eliciting CMF that triggered anaphylaxis, with or without supplemented prebiotics (scGOS) and with scGOS fractions containing oligosaccharides of different chain lengths.
  
  
  RESULTS
  The median age of presentation was 6 years (range, 5-38 years). Anaphylaxis occurred within 30 minutes of the first known exposure to CMF supplemented with prebiotics in all patients. Only 1 patient was subjected to oral challenge, which resulted in an anaphylactic reaction. All patients demonstrated IgE sensitization through SPTs and BATs to scGOS and fractions of scGOS containing 3 sugar units or greater but not to cow's milk or long-chain fructo-oligosaccharide. Eight child control subjects tolerant to regular ingestion of scGOS-supplemented CMF and 1 adult volunteer were found to have negative results to scGOS through SPTs and BATs. In addition, in vitro BATs with donor basophils sensitized with sera from 2 of the 3 reported cases showed reactions to scGOS. The scGOS-induced basophil activation was inhibited in the presence of wortmannin, a phosphatidylinositol 3-kinase inhibitor.
  
  
  CONCLUSIONS
  This study describes an unusual form of IgE-mediated anaphylaxis triggered by low-molecular-weight oligosaccharides in scGOS. The primary sensitizer for this phenomenon requires further investigation.
authors.affiliation: Department of Paediatrics, KK Woman's and Children's Hospital, Singapore. Chiang.Wen.Chin@kkh.com.sg
authors.forename: Wen Chin
authors.initials: WC
authors.lastname: Chiang
authors.forename: Chiung-Hui
authors.initials: CH
authors.lastname: Huang
authors.forename: Genevieve V
authors.initials: GV
authors.lastname: Llanora
authors.forename: Irvin
authors.initials: I
authors.lastname: Gerez
authors.forename: Si Hui
authors.initials: SH
authors.lastname: Goh
authors.forename: Lynette P C
authors.initials: LP
authors.lastname: Shek
authors.forename: Alma J
authors.initials: AJ
authors.lastname: Nauta
authors.forename: Wilhelmina A
authors.initials: WA
authors.lastname: Van Doorn
authors.forename: Jacques
authors.initials: J
authors.lastname: Bindels
authors.forename: Laurien H
authors.initials: LH
authors.lastname: Ulfman
authors.forename: Karen
authors.initials: K
authors.lastname: Knipping
authors.forename: Dianne J
authors.initials: DJ
authors.lastname: Delsing
authors.forename: Edward F
authors.initials: EF
authors.lastname: Knol
authors.forename: Bee Wah
authors.initials: BW
authors.lastname: Lee
mesh_terms: D000293:Adolescent; D000328:Adult; D000707:Anaphylaxis / Q000175:diagnosis* / Q000276:immunology; D000818:Animals; D015549:Basophil Degranulation Test; D002417:Cattle; D002648:Child; D002675:Child, Preschool; D019587:Dietary Supplements; D005260:Female; D005526:Food, Formulated / Q000009:adverse effects*; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood; D008297:Male; D008892:Milk / Q000009:adverse effects*; D016269:Milk Hypersensitivity / Q000175:diagnosis* / Q000276:immunology; D009844:Oligosaccharides / Q000276:immunology*; D012130:Respiratory Hypersensitivity / Q000175:diagnosis* / Q000276:immunology; D012882:Skin Tests; D055815:Young Adult
chemical_list: D009844:Oligosaccharides; D007073:Immunoglobulin E