title: Cow's milk challenge increases weakly acidic reflux in children with cow's milk allergy and gastroesophageal reflux disease.
abstract: OBJECTIVE
  To assess and compare the pattern of reflux in a selected population of infants with cow's milk (CM) allergy (CMA) and suspected gastroesophageal reflux disease (GERD) while on dietary exclusion and following challenge with CM.
  
  
  METHODS
  Seventeen children (median age: 14 months) with a proven diagnosis of CMA and suspected GERD underwent 48-hour multichannel intraluminal impedance-pH monitoring. For the first 24 hours, the infants were kept on amino acid-based formula, and for the subsequent 24 hours, they were challenged with CM.
  
  
  RESULTS
  The total reflux episodes and the number of weakly acidic episodes were higher during CM challenge compared with the amino acid-based formula period [total reflux episodes: 105 (58-127.5) vs 65 (39-87.5), P < .001; weakly acidic episodes: 53 (38.5-60.5) vs 19 (13-26.5), P < .001; median (25th-75th)]. No differences were found for either acid or weakly alkaline episodes (not significant). The number of weakly acidic episodes reaching the proximal, mid, and distal esophagus was higher during CM challenge (P < .001). No differences were found in either acid exposure time or number of long-lasting episodes (not significant).
  
  
  CONCLUSIONS
  In children with CMA and suspected GERD, CM exposure increases the number of weakly acidic reflux episodes. CM challenge during 48-hour multichannel intraluminal impedance-pH monitoring identifies a subgroup of patients with allergen-induced reflux, and in selected cases of children with CMA in whom GERD is suspected, its use could be considered as part of diagnostic work-up.
authors.affiliation: Neurogastroenterology and Motility Division, Department of Gastroenterology, Great Ormond Street Hospital for Sick Children and Institute of Child Health, London, United Kingdom. borreo@gosh.nhs.uk
authors.forename: Osvaldo
authors.initials: O
authors.lastname: Borrelli
authors.forename: Valentina
authors.initials: V
authors.lastname: Mancini
authors.forename: Nikhil
authors.initials: N
authors.lastname: Thapar
authors.forename: Valentina
authors.initials: V
authors.lastname: Giorgio
authors.forename: Mamoun
authors.initials: M
authors.lastname: Elawad
authors.forename: Susan
authors.initials: S
authors.lastname: Hill
authors.forename: Neil
authors.initials: N
authors.lastname: Shah
authors.forename: Keith J
authors.initials: KJ
authors.lastname: Lindley
mesh_terms: D002675:Child, Preschool; D017097:Electric Impedance; D005260:Female; D005745:Gastric Acidity Determination; D005746:Gastric Emptying / Q000502:physiology; D005764:Gastroesophageal Reflux / Q000175:diagnosis / Q000453:epidemiology*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007223:Infant; D008297:Male; D016269:Milk Hypersensitivity / Q000453:epidemiology*; D008991:Monitoring, Physiologic / Q000379:methods; D011446:Prospective Studies