Blood levels of leukotrienes (LTC4, D4, E4, B4) in asthmatic patients during attack and remission.

To assess the contribution of the leukotrienes, LTC4, D4, E4 and B4 during bronchial asthma attacks, simultaneous determination was made of their levels in venous blood. 25 patients with bronchial asthma (15 atopic types, 10 non-atopic types) participated in this study and 4 normal controls were used. Samples were obtained using heparinized syringe from the patients before treatment. A radioimmunoassay was conducted to measure LTs after purification with a Sep-pak column and separation by HPLC. In normal subjects, the levels were less than the minimal detectable amounts. LTC4, D4, E4 and B4 during asthmatic attacks were 100 +/- 179, 88 +/- 116, 479 +/- 291, and 55 +/- 73 (Mean +/- SD) pg/ml respectively (n = 27). Peptide LTs in remission were below minimal detectable levels. LTD4 in patients with moderate attacks was significantly (p < 0.05) higher than in those with mild attacks. Peptide LTs in moderate attack exceeded those in mild attacks, although not to a statistically significant degree. No significant differences in LT during attacks could be detected in atopic or non-atopic type patients. LTs would thus appear importantly involved in asthmatic attacks in atopic and non-atopic type patients, although other chemical mediators may give rise to airway inflammation.