Technical and practical issues for tidal breathing measurements of nasal nitric oxide in children.
To promote early screening of patients with suspected Primary Ciliary Dyskinesia (PCD), nasal nitric oxide (nNO) measurements during tidal breathing (TB) have been developed for children unable to ensure velum closure (VC) during breath hold or expiration against resistance. To investigate technical and practical issues related to TB-nNO methods in children referred for suspected or asserted PCD, we recorded, in a prospective multicenter study, TB-nNO (calculated as the mean of 5 peaks, 10 or 30 sec during tidal breathing) and VC-nNO when available. We studied 142 children (PCD diagnosis asserted in 47, excluded in 39). Nasal NO values were significantly different according to methods, VC-nNO being higher than TB-nNO (TB-nNO 5 peaks higher than mean of 10 or 30 sec). Specificity (90-94%) and sensitivity (86-97%) were similar between TB-nNO and VC-nNO methods. Age was more correlated with VC-nNO than with TB-nNO. TB-nNO could differ between the two nostrils by more than 10% (or 10 ppb when nNO absolute value lower 100 ppb) in 32-43% of the tested children, according to the different tidal breathing values, and was reproducible in the long term but influenced by ambient NO. Despite TB-nNO values being lower than VC-nNO, TB-nNO was found to be as discriminant for PCD, and probably more discriminant in children less than 8 years old, as the VC method. These results were obtained using the chemiluminescence technique which allows an easier assessment of relevant factors such as nasal permeability and ambient NO than the electrochemical technique.
APHP, Unité Fonctionnelle de Physiologie-Explorations Fonctionnelles Respiratoires, Hôpital Armand-Trousseau, Paris, France.|INSERM U938, Centre de Recherche Saint Antoine, Paris, France.
Nicole
N
Beydon
INSERM UMR915, Laboratoire d'Explorations Fonctionnelles, Faculté de médecine, CHU de Nantes, L'institut du thorax, Université de Nantes, France.
Arnaud
A
Chambellan
AP-HP, Hopital Robert Debré, Unité d'Epidémiologie Clinique, Paris, France.|Université Paris Diderot, Sorbonne Paris Cité, UMR-S 1123, Paris, France.|Inserm, CIC-EC 1426 et U1123, Paris, France.
Corinne
C
Alberti
APHP, Service de Pneumologie et Allergologie Pédiatriques, Hôpital Necker-Enfants Malades, Paris, France.|Université Paris Descartes, Paris, France.
Jacques
J
de Blic
AP-HP, Centre de Référence des Maladies Respiratoires Rares, Service de pneumologie pédiatrique, Hôpital Armand-Trousseau, Paris, France.|Université Pierre et Marie Curie, Paris, France.
Annick
A
Clément
INSERM UMR_S933, Université Pierre et Marie Curie (UPMC) - Paris 6; et service de Génétique et Embryologie médicales, AP-HP, Hôpital Armand Trousseau, Paris, France.
Estelle
E
Escudier
APHP, Service de Pneumologie et Allergologie Pédiatriques, Hôpital Necker-Enfants Malades, Paris, France.
Muriel
M
Le Bourgeois
D000293:Adolescent; D000367:Age Factors; D001944:Breath Tests / Q000379:methods*; D002648:Child; D002675:Child, Preschool; D045853:Exhalation; D005260:Female; D006801:Humans; D007619:Kartagener Syndrome / Q000175:diagnosis*; D008297:Male; D009569:Nitric Oxide / Q000378:metabolism*; D011446:Prospective Studies
D009569:Nitric Oxide
children; diagnosis; nasal airflow; primary ciliary dyskinesia