Difference in small airway inflammation between type Ⅱ (bronchiolar obstruction) asthma and obstructive bronchiolitis

Ventilatory function and inflammatory cells in airways were compared between patients with type Ⅱ (bronchiolar obstruction) asthma and those with obstructive bronchiolitis. 1. Age and age at onset were higher in patients with type Ⅱ asthma than in those with obstructive bronchiolitis. IgE-mediated allergic reaction was observed in patients with type Ⅱ asthma, but not in those with obstructive bronchiolitis. 2. In ventilatory function tests, all ventilatory parameters examined were lower in patients with type Ⅱ asthma compared to those with obstructive bronchiolitis, and the differences were significant in FEV1.0% (p<0.001), % MMF (p<0.02), and V50 (p<0.01). 3. The proportion of BAL neutrophils was very high in type Ⅱ asthma (55.7%) and obstructive bronchiolitis (74.4%), however, this was not significant. 4. Absolute numbers/BAL fluid of total cells, BAL macrophages and BAL neutrophils were significantly higher in patients with obstructive bronchiolitis than in those with type Ⅱ asthma. 5. The results on absolute number/mℓ of BAL cells demonstrated that number of BAL neutrophils markedly larger in patients with obstructive bronchiolitis compared to those with type Ⅱ asthma. These results show that high proportion of BAL neutrophils was observed in the two respiratory diseases, however, the degree of inflammation in airways was markedly greater in obstructive bronchiolitis.

Ⅱ型喘息と閉塞性細気管支炎の臨床的特徴について,換気機能および気道炎症反応を中心に検討を加えた｡1.年齢,および発症年齢とも閉塞性細気管支炎に比べⅡ型喘息において高い傾向が見られた｡IgE系反応はⅡ型喘息では観察されたが,閉塞性細気管支炎では見られなかった｡2.換気機能では,測定された全ての換気パラメーターにおいて,その値は閉塞性細気管支炎に比べⅡ型喘息でより低い値を示し,FEV1.0%,% MMFおよび% V50では有意の差が見られた｡3.BAL液中好中球頻度は,Ⅱ型喘息(55.7%),閉塞性細気管支炎(74.4%)いずれにおいても高い値を示したが,両者間に有意の差は見られなかった｡4.一方,BAL液中の絶対数では,Ⅱ型喘息に比べ,閉塞性細気管支炎において,総細胞数,マクロファージおよび好中球数が有意の高値を示した｡5.また,lmℓあたりの細胞数の比較でも,閉塞性細気管支炎で好中球数が著明な高値を示した｡これらの結果より,この2疾患では気道内好中球増多は同様に見られるものの,その気道炎症の程度は明らかに閉塞性細気管支炎でより高度であることが示された｡