Original Article
Bronchoalveolar lavage cellular composition in acute asthma and acute bronchiolitis

https://doi.org/10.1067/mpd.2000.108392Get rights and content

Abstract

Objective: To compare cellular inflammation in the airways between acute bronchiolitis and asthma. Study design: Using a bronchoalveolar lavage with flexible bronchoscopy procedure, we investigated the cellular constituents of BAL fluid in children with acute exacerbation of asthma (n = 18) and infants with acute bronchiolitis caused by respiratory syncytial virus (n = 20). These results were compared with those of healthy control subjects (n = 14). Results: Total lavage fluid recovered was similar in all groups. The total cell numbers were highest in the bronchiolitis group. The BAL cellular profile in the asthma group was characterized by a higher median (interquartile range) ratio of eosinophils (2.4% [1.6%-9.5%]; P <.01) than in the bronchiolitis group (0% [0%-0%]) or the control group (0% [0%-0%]). Neutrophil ratio was higher in the bronchiolitis group (40.0% [26.5%-50.0%]; P <.01), with no difference found between the asthma group (3.3% [2.0%-7.9%]) and the control group (2.0% [0.8%-5.5%]). Conclusions: Asthma and acute bronchiolitis are characterized by an elevated cellular percentage of eosinophils and neutrophils, respectively, in bronchoalveolar lavage fluid. (J Pediatr 2000;137:517-22)

Section snippets

Study Population

The study subjects included 18 patients with asthma, 20 patients with respiratory syncytial virus bronchiolitis, and 14 control subjects who underwent FB with BAL. Fifty-six subjects were originally included in the study. However, 4 cases had to be excluded from the analysis because of positive viral cultures in 2 patients with asthma (adenovirus and influenza A, respectively), an insufficient lavage return in 1 patient with RSV bronchiolitis, and a positive bacterial culture (Streptococcus

Results

Comparisons of the 3 groups showed that children with RSV bronchiolitis were significantly younger than children in the other 2 groups and that those with asthma had significantly higher serum IgE levels and blood eosinophil counts (Table I).

. Characteristics of the subjects

Empty CellAsthma group (n =18)Bronchiolitis group (n = 20)Control group (n = 14)
Age (y)*5.1 (2.0-10.2)0.7†‡ (0.4-2.0)6.0 (3.4-10.6)
Sex (M:F)12:611:910:4
Serum IgE (IU/mL)*259†§ (110-1568)16 (6-58)119 (40-298)
Blood eosinophils (/mm3)*465†§

Discussion

Our results show that neutrophils were the predominant cells in BAL fluid from children with RSV bronchiolitis and that the most consistent cellular finding in children with asthma was an increase in eosinophil number. It seems likely that neutrophils contribute significantly to inflammation within the airways in RSV bronchiolitis, whereas eosinophils play a crucial role in the airway inflammation in asthma. Our results indicate that there is a differential elevation of inflammatory cells in

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  • Cited by (0)

    Reprint requests: Young Yull Koh, MD, Department of Pediatrics, Seoul National University Hospital, 28 Yongon-dong, Chongno-gu, Seoul 110-744, Korea.

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