Induced sputum in adolescents with severe stable asthma. Safety and the relationship of cell counts and eosinophil cationic protein to clinical severity

• Published in: The European respiratory journal Vol. 13; no. 3; pp. 647 - 653
• Main Authors: Grootendorst, DC, van den Bos, JW, Romeijn, JJ, Veselic-Charvat, M, Duiverman, EJ, Vrijlandt, EJ, Sterk, PJ, Roldaan, AC
• Format: Journal Article
• Language: English
• Published: Leeds Eur Respiratory Soc 01.03.1999; Maney
• Subjects: Adolescent; Albuterol; Asthma - diagnosis; Biological and medical sciences; Biomarkers - analysis; Blood Proteins - analysis; Bronchial Provocation Tests; Cell Count; Chronic obstructive pulmonary disease, asthma; Cross-Sectional Studies; Diagnostic Techniques and Procedures - adverse effects; Eosinophil Granule Proteins; Female; Humans; Inflammation Mediators - analysis; Male; Medical sciences; Monitoring, Physiologic - methods; Pneumology; Prognosis; Quality of Life; Reproducibility of Results; Respiratory Function Tests; Ribonucleases; Sputum - chemistry; Sputum - cytology; Human; Respiratory disease; Induction; Exploration; Morbidity; Asthma; Numeration; Surveillance; Adolescent; Sputum; Severity score; Obstructive pulmonary disease; Eosinophil cationic protein; Cell
• ISSN: 0903-1936; 1399-3003
• DOI: 10.1183/09031936.99.13364799

This study examined the safety of sputum induction and the relation between sputum cell counts and clinical parameters in adolescents with severe persistent asthma. Within 5 days, induced sputum and reversibility in forced expiratory volume in one second (FEV1), quality of life, provocative concentration causing a 20% fall in FEV1 (PC20) of adenosine monophosphate and histamine, exercise-induced bronchoconstriction, overall asthma severity index, and blood eosinophils were collected in 20 atopic adolescents with moderate-to-severe persistent asthma (12-18 yrs of age, FEV1 65-110% of predicted, on 500-2,000 microg inhaled steroids daily). FEV1 was reversible by 13.3-2.3% pred. After sputum induction, FEV1 was still increased by 9.0+/-2.6% pred as compared to the pre-salbutamol baseline. Sputum contained, median (range): 12.4 (0.4-59.5)% squamous cells, 47.3 (6.8-84.0)% macrophages, 39.0 (4.6-84.8)% neutrophils, 4.8 (1.0-12.4)% lymphocytes, 0.4 (0-10.8)% eosinophils and 3.6 (0-23.4)% bronchial epithelial cells. Sputum eosinophils showed a trend towards a significant association with the overall asthma severity index (r=0.46, p=0.06) and correlated inversely with baseline FEV1 (r=-0.51, p=0.03). In conclusion, sputum can be induced safely in adolescents with moderate-to-severe persistent asthma, if pretreated with beta2-agonists. Despite relatively low sputum eosinophil counts in these patients on inhaled steroids, the association of eosinophil numbers with baseline forced expiratory volume in one second and asthma severity index favours a role of induced sputum in monitoring adolescents with severe asthma.