Urinary leukotriene E4 as a biomarker of exposure, susceptibility and risk in asthma.

Measurement of urinary leukotriene E(4) (uLTE(4)) is a sensitive and noninvasive method of assaying total body cysteinyl leukotriene production and changes in cysteinyl leukotriene production. Recent studies have reported on novel uLTE(4) receptor interactions, and new applications for uLTE(4), as a biomarker of environmental exposure to tobacco smoke and ambient air pollution, a predictor of risk for asthma exacerbations related to tobacco smoke, and a marker of susceptibility to leukotriene receptor antagonists.