IgE antibodies against inhalant allergens in patients with pulmonary emphysema

To analyze the pathophysiological changes ot the airways in emphysema, bronchial responsiveness and the generation of leukotrienes B4 (LTB4) and C4 (LTC4) by peripheral leucocytes were examined in 22 patients with emphysema. The subjects were divided into two groups according to the presence or absence of IgE antibodies against inhalant allergens; RAST positive group and RAST negative group. 1. Smoking history, mean CT number and mean maximum % low attenuation area (% LAA) <-950HU of the lung on high resolution computed tomography (HRCT), and DLco value suggested that there were emphysematous changes of the lung in all subjects. However, these findings were not different between the two groups. 2. The level of serum IgE was significantly higher in RAST positive group than in RAST negative group. 3. The mean % increase in FEV1.0 after inhalation of β-agonists was higher in RAST positive group than in RAST negative group. The % increase more than 15% was found in 4 of the 9 subjects (44.4%) in RAST positive group and 2 of the 12 (16.7%) in RAST negative group. 4. The generation of LTC4 by leucocytes was significantly higher in RAST positive group than in RAST negative group (p<0.01). The generation of LTB4 was not significantly different between the two groups. The results suggest that IgE-mediated allergy participates in the bronchial responsiveness of patients with emphysema.

肺気腫患者の気道病変を解析する目的で,22例の肺気腫患者を対象に,その気道反応および白血球のロイコトリエンB4,C4産生能について検討を加えた｡この際対象症例はIgE抗体の有無によってRAST陽性症例RAST陰性症例に分類された｡1.喫煙歴,平均CT値,high resolution computed tomography(HRCT)上の-950HU以下の% low attenuation area(% LAA),DLcoなどの値は,いずれも対象症例が高度な気腫化病変を有してい ることを示した｡2.血清IgE値は,RAST陽性例で陰性例に比べ有意の高値を示した｡3.β受容体刺激薬吸入後のFEV1.0の増加は,RAST陽性例で陰性例に比べ高度であった｡そして,吸入後のFEV1.0が15%以上の増加を示した症例は,RAST陽性例では9例中4例(44.4%),陰性例では12例中2例(16,7%)であった｡4.白血球のLTC4産生量は,RAST陽性例で陰性例に比べ有意に高い値であったが,LTB4産生は両者間に有意の差は見られなかった｡以上の結果より,IgEにmediateされるアレルギー反応が,肺気腫患者 の気道反応に関与している可能性が示唆された。