title: Fractional exhaled nitric oxide in infants during cow's milk food challenge.
abstract: Cow's milk allergy (CMA) is the most common food allergy in early childhood. The golden standard for the diagnosis of CMA is a food challenge after a period of elimination. Increased levels of fractional exhaled nitric oxide (FE(NO)) have been shown after bronchial allergen provocation. We evaluated whether FE(NO) may also be a predictor of a positive reaction during cow's milk challenge in infants. Forty-four infants [mean age (range): 4.2 (3.7-4.6) months] suspected of CMA underwent an open food challenge with cow's milk formula administered in ascending quantities, starting with 2 ml and then 6, 20, 60 and 200 ml until a clinical reaction occurred. Off-line FE(NO) samples were obtained during tidal breathing by means of a facemask covering infants' nose and mouth. FE(NO) was measured twice before the challenge (baseline), immediately before each new dose of milk and after a positive reaction or after the last dose of milk. Eleven children showed immediate positive clinical responses to cow's milk, whereas 13 infants presented only a late-type reaction. FE(NO) values before or after a positive reaction (either immediate or late) were not different from FE(NO) values at baseline. Baseline FE(NO) in infants with a positive reaction did not differ from FE(NO) in infants without a reaction at any time point. We conclude that FE(NO) values are not predictive and not related to the occurrence of a positive reaction during a cow's milk challenge in infants, suggesting that a positive reaction may not result from eosinophilic activation.
authors.affiliation: Department of Pediatrics, The Generation R Study Group, Erasmus University Medical Centre, Sophia Children's Hospital, Rotterdam, The Netherlands.
authors.forename: Carmelo
authors.initials: C
authors.lastname: Gabriele
authors.forename: Jeroen
authors.initials: J
authors.lastname: Hol
authors.forename: Evelien
authors.initials: E
authors.lastname: Kerkhof
authors.forename: Beatrix E E
authors.initials: BE
authors.lastname: Elink Schuurman
authors.forename: Janneke N
authors.initials: JN
authors.lastname: Samsom
authors.forename: Wim
authors.initials: W
authors.lastname: Hop
authors.forename: Edward E S
authors.initials: EE
authors.lastname: Nieuwenhuis
authors.forename: Johan C
authors.initials: JC
authors.lastname: de Jongste
mesh_terms: D000485:Allergens / Q000009:adverse effects*; D000818:Animals; D001985:Bronchial Provocation Tests; D004306:Dose-Response Relationship, Immunologic; D045853:Exhalation; D005260:Female; D006801:Humans; D007223:Infant; D041943:Infant Formula / Q000008:administration & dosage*; D008297:Male; D008892:Milk / Q000009:adverse effects*; D016269:Milk Hypersensitivity / Q000175:diagnosis / Q000276:immunology* / Q000503:physiopathology; D009569:Nitric Oxide / Q000276:immunology / Q000378:metabolism*; D011237:Predictive Value of Tests; D011379:Prognosis
chemical_list: D000485:Allergens; D009569:Nitric Oxide