TY - JOUR
T1 - Comparison of inflammatory cell counts in asthma: induced sputum vs bronchoalveolar lavage and bronchial biopsies
AU - Grootendorst, D. C.
AU - Sont, J. K.
AU - Willems, L. N.
AU - Kluin-Nelemans, J. C.
AU - van Krieken, J. H.
AU - Veselic-Charvat, M.
AU - Sterk, P. J.
PY - 1997
Y1 - 1997
N2 - Induced sputum potentially allows monitoring of airway inflammation in patients with asthma in a non-invasive way. However, the relationship between the cellular content in sputum and airway tissue has not been fully clarified. We compared the cellular compositions of hypertonic saline-induced sputum, bronchoalveolar lavage fluid (BAL) and bronchial biopsies in 18 clinically stable patients with mild to moderate atopic asthma (baseline FEV1: range 61-114%pred, PC20 methacholine: 0.04-4.7 mg/mL). They were treated with inhaled short-acting bronchodilators on demand, with (n = 8) or without (n = 10) regular inhaled steroids. Each patient underwent sputum induction and fiberoptic bronchoscopy on separate days in random order. Differential cell counts of induced sputum, bronchoalveolar lavage and bronchial wash were determined on May-Grünwald-Giemsa stained cytospins. Flow cytometry was performed on sputum and BAL samples. Immunohistochemical techniques were used to stain inflammatory cells in 6 microm cryostat sections of bronchial biopsies. Sputum cell differentials were not different between the patients with and without inhaled steroids, and showed a median value of 19.4% squamous cells, with 1.0% eosinophils, 3.3% lymphocytes, 28.7% neutrophils, 49.4% macrophages and 6.9% cylindric epithelial cells (in percentage non-squamous cells). The percentage eosinophils in sputum was significantly correlated with their percentage in bronchial wash (Rs = 0.52, P = 0.03) and in BAL (Rs = 0.55, P= 0.02), whilst there was a trend towards such a correlation between the number of eosinophils/mL sputum and the number of EG2+ eosinophils/mm2 lamina propria in bronchial biopsies (Rs = 0.44, P = 0.07). In addition, the percentage of CD4+ lymphocytes correlated between sputum and BAL (Rs = 0.55, P = 0.03). We conclude that the eosinophil counts in hypertonic saline-induced sputum from patients with asthma are related to those in bronchial wash and BAL and, to a lesser extent, with the counts in bronchial biopsies. This suggests that induced sputum can be used to monitor the presence and severity of airway inflammation in asthma
AB - Induced sputum potentially allows monitoring of airway inflammation in patients with asthma in a non-invasive way. However, the relationship between the cellular content in sputum and airway tissue has not been fully clarified. We compared the cellular compositions of hypertonic saline-induced sputum, bronchoalveolar lavage fluid (BAL) and bronchial biopsies in 18 clinically stable patients with mild to moderate atopic asthma (baseline FEV1: range 61-114%pred, PC20 methacholine: 0.04-4.7 mg/mL). They were treated with inhaled short-acting bronchodilators on demand, with (n = 8) or without (n = 10) regular inhaled steroids. Each patient underwent sputum induction and fiberoptic bronchoscopy on separate days in random order. Differential cell counts of induced sputum, bronchoalveolar lavage and bronchial wash were determined on May-Grünwald-Giemsa stained cytospins. Flow cytometry was performed on sputum and BAL samples. Immunohistochemical techniques were used to stain inflammatory cells in 6 microm cryostat sections of bronchial biopsies. Sputum cell differentials were not different between the patients with and without inhaled steroids, and showed a median value of 19.4% squamous cells, with 1.0% eosinophils, 3.3% lymphocytes, 28.7% neutrophils, 49.4% macrophages and 6.9% cylindric epithelial cells (in percentage non-squamous cells). The percentage eosinophils in sputum was significantly correlated with their percentage in bronchial wash (Rs = 0.52, P = 0.03) and in BAL (Rs = 0.55, P= 0.02), whilst there was a trend towards such a correlation between the number of eosinophils/mL sputum and the number of EG2+ eosinophils/mm2 lamina propria in bronchial biopsies (Rs = 0.44, P = 0.07). In addition, the percentage of CD4+ lymphocytes correlated between sputum and BAL (Rs = 0.55, P = 0.03). We conclude that the eosinophil counts in hypertonic saline-induced sputum from patients with asthma are related to those in bronchial wash and BAL and, to a lesser extent, with the counts in bronchial biopsies. This suggests that induced sputum can be used to monitor the presence and severity of airway inflammation in asthma
U2 - https://doi.org/10.1046/j.1365-2222.1997.890900.x
DO - https://doi.org/10.1046/j.1365-2222.1997.890900.x
M3 - Article
C2 - 9249269
SN - 0954-7894
VL - 27
SP - 769
EP - 779
JO - Clinical and experimental allergy
JF - Clinical and experimental allergy
IS - 7
ER -