Clinical features of type Ⅱ asthma (bronchiolar obstruction) without bronchoalveolar neutrophilia

Clinical features of asthma patients with bronchiolar obstruction (type Ⅱ asthma) were studied in relation to the proportion of neutrophils in bronchoalveolar lavage (BAL) fluid. Of 13 subjects studied, 7 were accompanied with BAL neutrophilia (53.5%) (BALn(+)) and 6 were without BAL neutrophilia (3.5%) (BALn(-)). 1. The mean age was higher in BALn(-) (66.0 years) than in BALn(+) patients (55.0 years). 2. Bronchial reactivity to methacholine was slightly higher in BALn(-) patients than in those with BALn(+). 3. The value of FEV1.0% was significantly lower in BALn(+) patints than in those with BALn(-) (p<0.01). 4. The proportion of BAL lymphocytes was signicantly more decreased in BALn(+) patients compared to the proportion in those with BALn(-) (p<0.001). 5. the values of serum IgG, IgA, and IgM were not significantly different between BALn(+) and BALn(-) patients, however, the value of IgG was more decreased in BALn(+) patients than in those with BALn(-). These results suggest that two kinds of type Ⅱ asthma ; one is with BAL neutrophilia related to suppressed immunity, and another is without BAL neutrophilia in part due to aging.

細気管支閉塞型(Ⅱ型)喘息の臨床的特徴が,BAL液中の好中球頻度との関連のもとに検討された｡対象13例のうち,7例がBAL液中好中球増加(平均好中球頻度;53.5%)をともなう症例(BALn(+))で,残りの6例はBAL液中好中球増加 をともなわない(3.5%)症例(BALn(-))であった｡1.平均年齢は,BALn(+)症例(55.0才)に比べ,BALn(-)症例(66.0才)でより高い傾向が見られた｡2.メサコリンに対する気道過敏性は,BALn(+)症例に比べBALn(-)症例でやや高い傾向が見られたが,両者間に有意の差は見られなかった｡3.FEV1.0%値は,BALn(-)症例に比べBALn(+)症例で有意に低い値を示した(P<0.05)｡4.BAL液中リンパ球頻度はBALn(+)症例でBALn(-)症例に比べ有意に低い値を示した(P<0.001)｡5.血清IgG,IgAおよびIgM値には両者間に有意の差は見られなかったが,IgG値はBALn(+)症例でより低い傾向が見られた｡これらの結果より,Ⅱ型喘息にはBAL液中好中球増加を示す症例と示さない症例の2種類があること,そして前者は免疫能の低下と,そして後者は加齢とある程度の関連があることが示唆された｡