title: Non-invasive pulmonary function test on Morquio patients.
abstract: In clinical practice, respiratory function tests are difficult to perform in Morquio syndrome patients due to their characteristic skeletal dysplasia, small body size and lack of cooperation of young patients, where in some cases, conventional spirometry for pulmonary function is too challenging. To establish feasible clinical pulmonary endpoints and determine whether age impacts lung function in Morquio patients non-invasive pulmonary tests and conventional spirometry were evaluated. The non-invasive pulmonary tests: impulse oscillometry system, pneumotachography, and respiratory inductance plethysmography in conjunction with conventional spirometry were evaluated in twenty-two Morquio patients (18 Morquio A and 4 Morquio B) (7 males), ranging from 3 to 40 years of age. Twenty-two patients were compliant with non-invasive tests (100%) with the exception of IOS (81.8%-18 patients). Seventeen patients (77.3%) were compliant with spirometry testing. All subjects had normal vital signs at rest including >95% oxygen saturation, end tidal CO2 (38-44 mmHg), and age-appropriate heart rate (mean=98.3, standard deviation=19) (two patients were deviated). All patients preserved normal values in the impulse oscillometry system, pneumotachography, and respiratory inductance plethysmography, although predicted forced expiratory total (72.8±6.9 SE%) decreased with age and was below normal; phase angle (35.5±16.5°), %rib cage (41.6±12.7%), resonant frequency, and forced expiratory volume in 1 s/forced expiratory volume total (110.0±3.2 SE%) were normal and not significantly impacted by age. The proposed non-invasive pulmonary function tests are able to cover a greater number of patients (young patients and/or wheel-chair bound), thus providing a new diagnostic approach for the assessment of lung function in Morquio syndrome which in many cases may be difficult to evaluate. Morquio patients studied herein demonstrated no clinical or functional signs of restrictive and/or obstructive lung disease.
authors.affiliation: Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, USA; Department of Biological Sciences, University of Delaware, Newark, DE, USA.
authors.forename: Francyne
authors.initials: F
authors.lastname: Kubaski
authors.affiliation: Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, USA; Department of Pediatrics, Gifu University, Gifu, Japan. Electronic address: stomatsu@nemours.org.
authors.forename: Shunji
authors.initials: S
authors.lastname: Tomatsu
authors.affiliation: Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, USA.
authors.forename: Pravin
authors.initials: P
authors.lastname: Patel
authors.affiliation: Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, USA.
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Shimada
authors.affiliation: Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, USA.
authors.forename: Li
authors.initials: L
authors.lastname: Xie
authors.affiliation: Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, USA.
authors.forename: Eriko
authors.initials: E
authors.lastname: Yasuda
authors.affiliation: Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, USA; Department of Biological Sciences, University of Delaware, Newark, DE, USA.
authors.forename: Robert
authors.initials: R
authors.lastname: Mason
authors.affiliation: Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, USA.
authors.forename: William G
authors.initials: WG
authors.lastname: Mackenzie
authors.affiliation: Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, USA.
authors.forename: Mary
authors.initials: M
authors.lastname: Theroux
authors.affiliation: Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, USA.
authors.forename: Michael B
authors.initials: MB
authors.lastname: Bober
authors.affiliation: Department of Respiratory Care, Nemours/Alfred I. DuPont Hospital for Children, Wilmington, DE, USA.
authors.forename: Helen M
authors.initials: HM
authors.lastname: Oldham
authors.affiliation: Department of Pediatrics, Gifu University, Gifu, Japan.
authors.forename: Tadao
authors.initials: T
authors.lastname: Orii
authors.affiliation: Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, USA; Center for Pediatric Lung Research, Nemours/Alfred I. DuPont Hospital for Children, Wilmington, DE, USA. Electronic address: tshaffer@nemours.org.
authors.forename: Thomas H
authors.initials: TH
authors.lastname: Shaffer
mesh_terms: D000293:Adolescent; D000328:Adult; D000375:Aging; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D008168:Lung / Q000503:physiopathology; D008297:Male; D009085:Mucopolysaccharidosis IV / Q000503:physiopathology*; D012129:Respiratory Function Tests; D013147:Spirometry; D014797:Vital Capacity; D055815:Young Adult
keywords: Impulse oscillometry system; Morquio syndrome; Non-invasive pulmonary function test; Pneumotachography; Respiratory inductance plethysmography