[Bronchial exudate of serum proteins during asthma attack].
OBJECTIVE
Although altered vascular permeability and edema of the bronchial mucosa are associated with asthma attack, their influence on its severity remains unknown. We address this issue by comparing relative indices for the concentration of albumin (RIAlb) and alpha2-macroglobulin (RIalpha2M) in induced sputum and peripheral blood from patients with exacerbated asthma, patients with stable asthma, and control subjects.


METHODS
Forty-six volunteers participated in the study: 14 with exacerbated asthma (forced expiratory volume in the first second [FEV1] 74.3% [SD, 20.8%] of reference), 23 with stable asthma (FEV1 93.6% [7.5%]), and 9 controls (FEV1 101.1% [9.9%]). The concentrations of albumin and alpha2-macroglobulin were quantified by immunoturbidimetry and immunonephelometry, respectively. The relative index was then calculated by dividing the concentration in sputum supernatant by the concentration in peripheral blood.


RESULTS
The mean RIAlb was 1.2 (1.1) in the control group, 2.9 (3.1) in the stable asthma group, and 6.0 (6.7) in the exacerbated asthma group. The RIalpha2M values were 11.7 (10.9), 11.9 (14.7), and 3.2 (3.8) for the control group and stable and exacerbated asthma groups, respectively. The increases in the RIAlb values between all groups, and the decrease in the RIalpha2M value between the exacerbated asthma and control groups were statistically significant (P<.05). The percentage of neutrophils, but not of eosinophils, in sputum was correlated with the RIAlb (r=0.39; P=.008) but not the RIalpha2M (r=-0.035; P=.82). FEV1 displayed an inverse relationship with the RIAlb (r=-0.43; P=.009) but not with the RIalpha2M (r=-0.206; P=.24). No correlation was found between oxyhemoglobin saturation and either the RIAlb (r=-0.33; P=.19) or the RIalpha2M (r=-0.12; P=.84).


CONCLUSIONS
Vascular permeability is altered during asthma exacerbations and appears to be correlated with the presence of neutrophils and the degree of bronchial obstruction.
Belda
J
J
Clínica d'Asma i Allèrgia, Departament de Pneumologia, Hospital de la Santa Creu i de Sant Pau, Universitat Autònoma de Barcelona, Barcelona, Spain. jbelda@hsp.santpau.es
Margarit
G
G
Martínez
C
C
Casan
P
P
Rodríguez-Jerez
F
F
Brufal
M
M
Torrejón
M
M
Granel
C
C
Sanchis
J
J
D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D001249:Asthma / Q000097:blood / Q000503:physiopathology*; D001772:Blood Cell Count; D001798:Blood Proteins / Q000032:analysis*; D001980:Bronchi / Q000503:physiopathology*; D001985:Bronchial Provocation Tests; D002199:Capillary Permeability; D004804:Eosinophils; D005122:Exudates and Transudates / Q000737:chemistry* / Q000166:cytology; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D008264:Macrophages; D008297:Male; D016210:Methacholine Chloride; D008875:Middle Aged; D009391:Nephelometry and Turbidimetry; D009504:Neutrophils; D012709:Serum Albumin / Q000032:analysis; D013183:Sputum / Q000737:chemistry; D000511:alpha-Macroglobulins / Q000032:analysis
D001798:Blood Proteins; D012709:Serum Albumin; D000511:alpha-Macroglobulins; D016210:Methacholine Chloride