Clinical Research Of The Detection Of Urinary Leukotriene E₄ In Children With Asthma

Objective: To study the significance of measurement of urinary leukotriene E4 (LTE4) in monitoring the outcome of children with asthma and the relationship between urinary LTE4 and airway resistance(Rint), peripheral blood eosinophil count (EC).Methods: Thirty-five asthmatic children with mild to moderate acute episode aged from one to five years old who had never took leukotrienes receptor antagonist(LTA)-montelukast were selected. Urinary LTE4 of these children were measured by competitive enzyme linked immunosorbent assay( ELISA ) and expressed as pg/mg creatinine. Rint and peripheral blood EC were also investigated in these children. Urinary LTE4, Rint and peripheral blood EC of those thirty-five children who had been given montelukast for one month(chronic persistent stage) and three months(clinical remission stage) were also detected.Those children who experienced three asthmatic stage were set as asthmatic group.At same time,twenty healthy children were selected as control group. Urinary leukotrience E4 and Rint were measured in control group.Results: :1. Urinary LTE4 of acute attack stage,chronic persistent stage,clinical remission stage were:(234.03±7.00)pg/mg creatinine;(91.39±6.35)pg/mg creatinine; (54.57±4.84)pg/mg creatinine respectively and were significantly higher than the control group(22.10±6.34)pg/mg creatinine(t=39.67;37.81;20.51respectively,both P<0.01). Urinary LTE4 in three asthmatic stage was significantly different (F=870.08, P<0.01). 2. Rint of acute attack stage,chronic persistent stage,clinical remission stage were:(1.92±0.11)kPa/L/s;(1.30±0.12)kPa/L/s;(0.98±0.09)kPa/L/s respectively and were significantly higher than the control group(0.37±0.12)kPa/L/s(t=47.19;27.18; 20.62 respectively,both P<0.01). Rint in three asthmatic stage was significantly different (F=496.58, P<0.01).3.Peripheral blood EC in acute attack stage,chronic persistent stage,clinical remission stage were:(0.66±0.13)×109/L;(0.21±0.09)×109/L; (0.17±0.06)×109/L respectively and was significantly different (F=195.98, P<0.01). In acute attack period, there was no correlation between urinary LTE4 and Rint (r=0.11, P=0.58). And there was also no correlation between urinary LTE4 and EC(r=-0.12, P=0.52).Conclusion: Urinary LTE4 in acute attack period was significantly increased. Along with upturn of asthma, urinary LTE4 decreased gradually;Urinary LTE4 is a useful marker in guiding asthma diagnosis and treatment.