Epithelial damage and angiogenesis in the airways of children with asthma.
BACKGROUND
Airway remodeling and inflammation are characteristic features of adult asthma that are still poorly investigated in childhood asthma.


OBJECTIVE
To examine epithelial and vascular changes as well as the inflammatory response in airways of children with asthma.


METHODS
We analyzed bronchial biopsies obtained from 44 children undergoing bronchoscopy for appropriate clinical indications other than asthma: 17 with mild/moderate asthma (aged 2-15 yr), 12 with atopy without asthma (1-11 yr), and 15 control children without atopy or asthma (1-14 yr). By histochemistry and immunohistochemistry, we quantified epithelial loss, basement membrane thickness, number of vessels, and inflammatory cells in subepithelium.


RESULTS
Epithelial loss and basement membrane thickness were increased in children with asthma compared with control subjects (p = 0.005 and p = 0.0002, respectively) and atopic children (p = 0.002 and p = 0.005, respectively). The number of vessels and eosinophils was increased not only in asthmatic children (p = 0.03 and p = 0.0002, respectively) but also in atopic children without asthma (p = 0.03 and p = 0.008, respectively) compared with control subjects. When we stratified the analysis according to age, we observed that children with asthma younger than 6 yr had increased epithelial loss, basement membrane thickening, and eosinophilia compared with control subjects of the same age.


CONCLUSIONS
Epithelial damage and basement membrane thickening, which are pathologic features characteristic of adult asthma, are present even in childhood asthma. Other changes, such as airway eosinophilia and angiogenesis, were also observed in atopic children without asthma. These observations suggest that pathologic changes occur early in the natural history of asthma and emphasize the concept that some of these lesions may characterize atopy even in the absence of asthmatic symptoms.
Barbato
Angelo
A
Divisione di Pneumologia, Dipartimento di Scienze Cardiologiche, Toraciche e Vascolari Università degli Studi di Padova, via Giustiniani 3, Padova, Italy.
Turato
Graziella
G
Baraldo
Simonetta
S
Bazzan
Erica
E
Calabrese
Fiorella
F
Panizzolo
Cristina
C
Zanin
Maria Elena
ME
Zuin
Renzo
R
Maestrelli
Piero
P
Fabbri
Leonardo M
LM
Saetta
Marina
M
D000293:Adolescent; D001249:Asthma / Q000473:pathology* / Q000503:physiopathology*; D001485:Basement Membrane / Q000473:pathology; D001980:Bronchi / Q000473:pathology* / Q000503:physiopathology*; D001999:Bronchoscopy; D002648:Child; D002675:Child, Preschool; D004847:Epithelial Cells / Q000473:pathology*; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D007223:Infant; D008297:Male; D009389:Neovascularization, Pathologic