Leukotriene E-4 plasma levels in adult asthmatic patients with variable disease severity

Cysteinyl leukotrienes (C-LTs) are local inflammatory mediators involved in bronchial asthma. Seventeen asthmatic patients (FEV1 ranging from 41 to 99.8% of predicted values) and 11 healthy subjects were studied. The clinical severity of asthma was assessed by the Aas score. Plasma C-LTs were measured by enzyme immunoassay (EIA) after sample purification by solid-phase extraction (SPE), to investigate whether differences may exist between asthmatic and control subjects and whether leukotriene E-4 (LTE4) levels were related to the severity of disease. LT measurements showed that 87.6+/-1.2% was recovered as LTE4 and 9.4+/-1.3% as LTC4. In asthmatic subjects, LTE4 plasma levels were found to be significantly higher than those in the control group (1.073+/-0.133 and 0.53+/-0.19 ng/ml of plasma, respectively; P < 0.002). Moreover, there was a significant correlation between LTE4 plasma levels and the Aas clinical score (P < 0.005). These data suggest that plasma LTE4 levels might be used to assess the severity of asthma.