title: Predictive value of infant lung function testing for airway malacia.
abstract: Airway malacia is present in a small proportion of wheezing infants. The usefulness of infant lung-function testing (ILFT) in ruling out malacia in wheezy infants is unknown. We assessed the predictive value of ILFT parameters for airway malacia diagnosed by flexible bronchoscopy. Thirty-two term infants (mean (SD) age, 11.0 (4.6) months) with chronic wheeze unresponsive to asthma treatment underwent ILFT prior to bronchoscopy. Functional residual capacity measured by plethysmograph (FRCp), maximal flow at FRC (V'max(FRC)), and tidal breathing parameters were obtained. Expiratory flow-volume curves were visually examined for tidal flow limitation. Malacia was observed during bronchoscopy in 20 infants. V'max(FRC) (Z-score) was significantly lower in the group with malacia as compared with the group without malacia. Lung-function measurements had a low negative predictive value and sensitivity. While flow limitation during tidal breathing was highly predictive and 100% specific for airway malacia, only half of the infants with malacia had tidal flow limitation. In this selected group of infants, routine lung function testing could not discriminate between infants with and without airway malacia. However, the presence of tidal flow limitation was 100% predictive and specific for airway malacia.
authors.affiliation: Department of Pediatrics, Division of Respiratory Medicine, Erasmus Medical Center-Sophia Children's Hospital/University Medical Center Rotterdam, Rotterdam, The Netherlands.
authors.forename: Els C
authors.initials: EC
authors.lastname: van der Wiel
authors.forename: Ward
authors.initials: W
authors.lastname: Hofhuis
authors.forename: Wim P J
authors.initials: WP
authors.lastname: Holland
authors.forename: Harm A W M
authors.initials: HA
authors.lastname: Tiddens
authors.forename: Johan C
authors.initials: JC
authors.lastname: de Jongste
authors.forename: Peter J F M
authors.initials: PJ
authors.lastname: Merkus
mesh_terms: D001982:Bronchial Diseases / Q000175:diagnosis* / Q000503:physiopathology; D001999:Bronchoscopy; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D010991:Plethysmography; D011237:Predictive Value of Tests; D012129:Respiratory Function Tests; D012135:Respiratory Sounds / Q000502:physiology*; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D014133:Tracheal Diseases / Q000175:diagnosis* / Q000503:physiopathology