title: Impairment of nitric oxide output of conducting airways in primary ciliary dyskinesia.
abstract: Nasal nitric oxide (NO) concentration is dramatically reduced in primary ciliary dyskinesia (PCD). The aims of this study were to apply a multiple-flow NO analysis to investigate whether NO output from the bronchial tree was affected in a similar way to nasal NO output, and to search for a relationship between flow-independent exchange parameters and airflow limitation. Multiple flow rate analysis of exhaled NO, allowing the calculation of maximum airway wall flux and alveolar NO concentration, was performed in 17 PCD patients (median age, 25-75th percentiles: 13.5, 12.1-17.6) with documented ultrastructural cilia abnormalities and 28 healthy subjects (16.0, 11.0-21.0). Median maximum airway wall flux and median alveolar NO concentration were significantly reduced in PCD patients compared to healthy subjects: 16.0, 7.5-29.5, vs. 25.0, 15.0-32.5 nl/min (P<0.05) and 2.5, 1.6-3.3, vs. 5.0, 3.6-6.5 ppb (P<0.01), respectively. Significant correlations between maximum airway wall flux and airflow limitation were found, i.e., resistance of respiratory system (rho=0.74, P<0.005), forced expiratory volume in one second (FEV(1))/VC (rho= -0.61, P<0.05), FEV(1) (rho=-0.52, P< 0.05), mid expiratory flow between 25 and 75% of forced vital capacity (MEF(25-75)) (rho=-0.54, P<0.05), and maximal instantaneous expiratory flow at 50% of the vital capacity (MEF(50)) (rho=-0.55, P<0.05). In conclusion, the impairment of NO output is less pronounced in the lower than in the upper (nasal) respiratory tract in PCD. A decrease in maximal NO output from conducting airways is associated with limited airflow impairment.
authors.affiliation: Service de Pneumologie-Allergologie Pédiatrique, Hôpital Necker Enfants Malades, Assistance Publique Hôpitaux des Paris, Paris, France. hali.fax@laposte.net
authors.forename: Bruno
authors.initials: B
authors.lastname: Mahut
authors.forename: Estelle
authors.initials: E
authors.lastname: Escudier
authors.forename: Jacques
authors.initials: J
authors.lastname: de Blic
authors.forename: Françoise
authors.initials: F
authors.lastname: Zerah-Lancner
authors.forename: André
authors.initials: A
authors.lastname: Coste
authors.forename: Alain
authors.initials: A
authors.lastname: Harf
authors.forename: Christophe
authors.initials: C
authors.lastname: Delclaux
mesh_terms: D000293:Adolescent; D000328:Adult; D015415:Biomarkers / Q000378:metabolism; D002648:Child; D002675:Child, Preschool; D005541:Forced Expiratory Volume / Q000502:physiology; D006801:Humans; D007619:Kartagener Syndrome / Q000378:metabolism* / Q000503:physiopathology; D009297:Nasal Mucosa / Q000378:metabolism* / Q000648:ultrastructure; D009569:Nitric Oxide / Q000378:metabolism*; D011379:Prognosis; D011650:Pulmonary Alveoli / Q000378:metabolism* / Q000648:ultrastructure; D013147:Spirometry
chemical_list: D015415:Biomarkers; D009569:Nitric Oxide