Nasal and lower airway level of nitric oxide in children with primary ciliary dyskinesia

Abstract

The aim of this study was to compare exhaled nitric oxide concentrations obtained during controlled slow exhalation, presently considered as the method of choice, with two sampling methods that are easily performed by children: blowing air into a balloon and tidal breathing through a mouthpiece.One hundred and one well controlled, stable allergic asthmatic children (median age 11.7 yrs) performed the following tasks in duplicate: 1) exhalation from total lung capacity through a mouthpiece against a resistor with a standardized flow rate of 20% of the subject's vital capacity per second, using a biofeedback system; 2) a single deep exhalation into an NO-impermeable mylar balloon; and 3) tidal breathing through a low resistance mouthpiece over 2 min. NO was measured using a chemiluminescence analyser.Twenty-nine children (29%) were not able to perform a constant-flow exhalation of at least 3 s. All children performed the balloon and tidal breathing methods without difficulty. NO concentrations (meansSEM) were 5.30.2 parts per billion (ppb) at the end-expiratory plateau, 5.20.3 ppb in balloons (intraclass correlation coefficient (r i )=0.73) and 8.00.4 ppb during tidal breathing (p<0.001, r i =0.53 compared to plateau values). Mean values of NO during tidal breathing increased significantly with time, suggesting increasing contamination with nasal air.It was concluded that, in asthmatic children, the end-expiratory plateau concentration of nitric oxide during exhalation at 20% of the vital capacity per second is similar to the values obtained with the balloon method, with satisfactory agreement, but differs from values obtained during tidal breathing. The balloon method is cheap, simple and offers the interesting possibility to study exhaled nitric oxide in young children independently of the presence of a nitric oxide analyser. Eur Respir J 1999; 13: 1406±1410.

Primary ciliary dyskinesia: a consensus statement on diagnostic and treatment approaches in children

“…A high or normal nasal NO level can help to exclude PCD, particularly in those in whom the history is not classical, but it should be noted that a few patients with PCD may have levels within the normal range [64]. A low measurement is not diagnostic of PCD, with low levels occurring in other conditions, including CF, panbronchiolitis, nasal blockage and nasal polyposis.…”

“…Nasal nitric oxide measurement A number of studies have shown that levels of exhaled nitric oxide, and particularly nasal NO, are very low in PCD [9,51,64,65]. A high or normal nasal NO level can help to exclude PCD, particularly in those in whom the history is not classical, but it should be noted that a few patients with PCD may have levels within the normal range [64].…”

Laterality Defects Other Than Situs Inversus Totalis in Primary Ciliary Dyskinesia

“…21 Measured nNO concentration was multiplied by sampling fl ow to determine nNO production in nanoliters per minute. For velum closure nNO and tidal breathing nNO, values , 77 nL/min 20,22,23 and , 40 nL/min, 21,24 respectively, were considered low and within PCD range. Velum closure nNO measurements were also collected from 77 healthy pediatric control participants.…”

Sequence analysis of 21 genes located in the Kartagener syndrome linkage region on chromosome 15q

“…All cases were confirmed by a low concentration of nitric oxide (NO) measured in exhaled air. 19 NO was measured from the nasal cavity by a chemiluminescence analyzer with a threshold value of 200 ppb for diagnosing PCD. In 60% of the families, the clinical diagnosis was confirmed by transmission electron microscopy analysis of bronchial cilia ultrastructure; the analysis revealed defects of outer or outer and inner dynein arms; a representative EM picture is shown in Supplementary Figure 1.…”