Clinical application of urinary leukotriene E4 in bronchial asthma / 천식및알레르기

ABSTRACT

BACKGROUND: Cysteinyl leukotrienes are important inflammatory mediators in bronchial asthma because they enhance microvascular permeability, increase nonspecific bronchial hyperresponsiveness, and are potent bronchoconstrictor agents. Leukotriene E4 is a major metabolite of cysteinyl leukotriene excreted in urine and its concentration of urine can be a reliable marker of the overall leukotriene production in the body. OBJECTIVE: To determine whether clinical parameters of bronchial asthma are associated with production of cysteinyl leukotrienes, expressed by urinary leukotriene E4. METHOD: We measured the urinary concentration of leukotriene E4 in bronchial asthma(127 patients) and normal control(15 persons) group by ELISA method. Pulmonary function test, allergic skin test, measurement of peripheral eosinophil count and eosinophil cationic protein were undertaken in bronchial asthma patients. RESULTS: The concentrations of urinary leukotriene E4 were significantly higher in bronchial asthma patients than normal controls (p<0.05). The increased concentrations of leukotriene E4 had a significant correlation with FEV1/FVC or methacholine PC20(p<0.05). However, the concentration of leukotriene E4 did not have any correlation with the presence of atopy, peripheral blood eosinophil count, and eosinophil cationic protein level. CONCLUSION: The concentration of urinary leukotriene E4 that represents the overall leukotriene production in the body is correlated with the degree of airway obstruction and airway hyperresponsiveness. So, the concentration of urinary leukotriene E4 may be used as an adjunctive parameter of airway obstruction and hyperresponsiveness in bronchial asthma.