Urinary leukotriene E4 and 11-dehydro-thromboxane B2 excretion in children with bronchial asthma

Abstract

Cysteinyl leukotrienes (CysLTs) and thromboxane (TX) A 2 have been implicated in the pathogenesis of bronchial asthma. Urinary leukotriene E 4 (LTE 4 ) and 11-dehydro-TXB 2 (11 DTXB 2 ) levels are often used to assess the production of CysLTs and TXA 2 . However, few studies have examined the products of these two mediators in the same asthmatic patients. To define the potential roles of CysLTs and TXA 2 in the pathogenesis of bronchial asthma in children, their urinary levels were measured in the present study. Urinary LTE 4 and 11DTXB 2 levels were measured by enzyme immunoassay (EIA) and radioimmunoassay (RIA), respectively. Urine samples from asthmatic children were measured during the stable condition and during an acute attack. Urinary LTE 4 levels during an acute attack (median 476 pg/mg creatinine; range 191–1100 pg/ mg creatinine) and during the stable condition (median 332 pg/mg creatinine; range 128–965 pg/ mg creatinine) were significantly higher (P < 0.05) than those of controls (median 233 pg/mg creatinine; range 103–389 pg/mg creatinine). Urinary 11DTXB 2 levels during an acute attack and during the stable condition (median 1666 (range 110–5105) and 1009 (range 46–6070) pg/mg creatinine, respectively) were significantly higher ( P < 0.05) than those of controls (median 252 pg/mg creatinine; range 41–716 pg/mg creatinine). Comparing different stages of asthma, LTE 4 levels during an acute attack were significantly higher (P < 0.05) than during the stable condition; however, there was no difference in urinary TXB2 levels. The present findings suggest that high levels of CysLTs and TXA 2 are associated with the pathogenesis of bronchial asthma. The measurement of urinary LTE 4 and 11DTXB 2 would be useful in understanding the individual pathogenesis of asthmatic children.