Pulmonary Function Tests in Preschool Children with Cystic Fibrosis

• Published in: American journal of respiratory and critical care medicine 2002-10, Vol.166 (8), p.1099-1104
• Main Authors: Beydon, Nicole, Amsallem, Francis, Bellet, Mireille, Boule, Michele, Chaussain, Michele, Denjean, Andre, Matran, Regis, Pin, Isabelle, Alberti, Corinne, Gaultier, Claude
• Format: Article
• Language: English
• Subjects: Airway Resistance; Biological and medical sciences; Bronchodilator Agents - therapeutic use; Child; Child, Preschool; Chronic obstructive pulmonary disease, asthma; Cystic Fibrosis - drug therapy; Cystic Fibrosis - genetics; Cystic Fibrosis - physiopathology; Cystic Fibrosis Transmembrane Conductance Regulator - genetics; Female; Functional Residual Capacity; Homozygote; Humans; Male; Medical sciences; Pneumology; Respiratory Mechanics; Tobacco Smoke Pollution - adverse effects
• ISSN: 1073-449X; 1535-4970
• DOI: 10.1164/rccm.200205-421OC

Pulmonary function tests have rarely been assessed in preschool children with cystic fibrosis (CF). The objective of this multicenter study was to compare pulmonary function in 39 preschool children with CF (height, 90-130 cm; 16 homozygous Delta F508) and in 79 healthy control children. Functional residual capacity (helium dilution technique) and expiratory interrupter resistance (Rint(exp)) (interrupter technique) were measured. As compared with control children, children with CF had significantly higher Rint(exp), expressed as absolute values and as Z-scores (1.05 +/- 0.36 versus 0.80 +/- 0.20 kPa.L(-1). second, p < 0.0001; and 1.31 +/- 1.72 versus 0.19 +/- 0.97, p < 0.0001), and significantly lower specific expiratory interrupter conductance (1.29 +/- 0.34 versus 1.63 +/- 0.43 kPa(-1). second, p < 0.0001). The effect of the bronchodilator salbutamol on Rint(exp) was not significantly different between children with CF and control children. Rint(exp) Z-scores were significantly higher in children with CF who were exposed to passive smoke (n = 8) (p < 0.03). Children with CF and with a history of respiratory symptoms (n = 31) had significantly higher functional residual capacity Z-scores (p < 0.02) and lower specific expiratory interrupter conductance Z-scores (p < 0.04). Genotype did not influence the data. We conclude that Rint(exp) and functional residual capacity measurements may help to follow young children with CF who are unable to perform reproducible forced expiratory maneuvers.