TY - JOUR
T1 - Epithelial desquamation in asthma
T2 - Artifact or pathology?
AU - Ordoñez, Claudia
AU - Ferrando, Ron
AU - Hyde, Dallas M.
AU - Wong, Hofer H.
AU - Fahy, John V.
PY - 2000
Y1 - 2000
N2 - To determine whether the denudation of the bronchial epithelium observed in endobronchial biopsies from asthmatic subjects is a true pathologic feature or an artifact of tissue sampling, we analyzed epithelial integrity in bronchial biopsies from 14 subjects with mild and moderate asthma and 12 healthy subjects. In each subject, 4 to 8 bronchial biopsies were taken from large airways during bronchoscopy, fixed in 4% paraformaldehyde, embedded in glycomethacrylate, cut into 2-μM sections, and stained with toluidine blue. A ×4 image of each biopsy was copied to a computer file using a video camera, and lines were drawn and measured along the basement membrane underlying areas completely denuded of overlying epithelium, areas covered by a single layer of basal cells, and areas of intact epithelium. We found that the percentage of basement membrane that was denuded of epithelium was similar in the healthy and asthmatic subjects (14.8 ± 11.8 versus 11.4 ± 9.8% respectively, p = 0.38); the percentage of basement membrane that was covered by a single layer of basal cells was also similar in the two groups (46.4 ± 11.0 versus 54.5 ± 9.8%, respectively, p = 0.11). In the asthmatic subjects, we found no significant correlation between the percentage of basement membrane covered by denuded epithelium or by a single layer of basal cells and the FEV1 percentage of predicted or the PC20 methacholine. We conclude that denudation of bronchial epithelium in endobronchial biopsies from asthmatic subjects with stable mild and moderate disease is an artifact of tissue sampling and is not a true pathologic feature of the disease, and that the extent of airway epithelial denudation is not correlated with the severity of airway narrowing or the severity of bronchial hyperresponsiveness.
AB - To determine whether the denudation of the bronchial epithelium observed in endobronchial biopsies from asthmatic subjects is a true pathologic feature or an artifact of tissue sampling, we analyzed epithelial integrity in bronchial biopsies from 14 subjects with mild and moderate asthma and 12 healthy subjects. In each subject, 4 to 8 bronchial biopsies were taken from large airways during bronchoscopy, fixed in 4% paraformaldehyde, embedded in glycomethacrylate, cut into 2-μM sections, and stained with toluidine blue. A ×4 image of each biopsy was copied to a computer file using a video camera, and lines were drawn and measured along the basement membrane underlying areas completely denuded of overlying epithelium, areas covered by a single layer of basal cells, and areas of intact epithelium. We found that the percentage of basement membrane that was denuded of epithelium was similar in the healthy and asthmatic subjects (14.8 ± 11.8 versus 11.4 ± 9.8% respectively, p = 0.38); the percentage of basement membrane that was covered by a single layer of basal cells was also similar in the two groups (46.4 ± 11.0 versus 54.5 ± 9.8%, respectively, p = 0.11). In the asthmatic subjects, we found no significant correlation between the percentage of basement membrane covered by denuded epithelium or by a single layer of basal cells and the FEV1 percentage of predicted or the PC20 methacholine. We conclude that denudation of bronchial epithelium in endobronchial biopsies from asthmatic subjects with stable mild and moderate disease is an artifact of tissue sampling and is not a true pathologic feature of the disease, and that the extent of airway epithelial denudation is not correlated with the severity of airway narrowing or the severity of bronchial hyperresponsiveness.
UR - http://www.scopus.com/inward/record.url?scp=0034523686&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0034523686&partnerID=8YFLogxK
M3 - Article
C2 - 11112158
AN - SCOPUS:0034523686
VL - 162
SP - 2324
EP - 2329
JO - American Journal of Respiratory and Critical Care Medicine
JF - American Journal of Respiratory and Critical Care Medicine
SN - 1073-449X
IS - 6
ER -