Association of the mean CT number by high resolution computed tomography (HRCT) with generation of leukotrienes B4 (LTB4) and C4 (LTC4) in patients with pulmonary emphysema

The generation of leukotrienes B4 (LTB4) and C4 (LTC4) by peripheral leukocytes stimulated with Ca ionophore A23187 was examined in 17 patients with pulmonary emphysema. They were divided into three groups according to the mean CT number; A (<-940 HU), B (-940 ≦, <-930 HU), and C (-930 HU ≦ ).1. The values of FVC (% predicted), FEV1.0% and DLco (% predicted) showed a tendency to decrease as the mean CT number was smaller. The value of % FVC was significantly lower in patients with group A than in those with group C (p<0.05). 2. The generation of both LTB4 and LTC4 was significantly higher in patients with emphysema compared to the generation in healthy subjects (LTB4;p<0.05, LTC4;P<0.05). 3. The generation of LTB4 and LTC4 in patients with emphysema was higher as the mean CT number was larger (severity of the disease become less). The LTC4 production was significantly higher in patients with group C(mild or moderate type of emphysema) than in those with group A(advanced type of emphysema). These results suggest that the generation of LTB4 and LTC4 is higher in patients with mild or moderate type of emphysema than in those with advanced type of the disease.

肺気腫患者17名を対象として,カルシウムイオノフォアA23187による末梢血白血球からのロイコトリエンB4(LTB4), ロイコトリエンC4(LTC4)の産生能の検討を行った｡対象は高分解能CTによる平均CT値によってA(<940HU), B(-940≦,<-930HU),C(-930HU≦)の3群に分類した｡1.% FVC,FEV1.0%,% DLcoが低下するにつれて平均CT値が低下する傾向が見られた｡% FVC値はC群に比較して,A群において有意に低値を示した(p<0.05)｡2.LTB4とLTC4の産生能は健常人に比較して,肺気腫患者において有意に高値を示した(LTB4;p<0.05,LTC4;p<0.05)。3.肺気腫患者におけるLTB4とLTC4の産生能は平均CT値が上昇するにつれて(軽症症例ほど)高値を示した｡またLTC4産生能はC群(早期肺気腫症例)においてA群(進行肺気腫症例)に比して有意に高値を示した｡以上より肺気腫におけるLTB4,LTC4産生能は進行例に比較すると,軽･中等症例において高値であることが示唆された｡