Urinary Leukotriene E 4 as a Biomarker of Exposure, Susceptibility, and Risk in Asthma: An Update.

Measurement of urinary leukotriene E4 (uLTE4 ) is a sensitive and noninvasive method of assaying total body cysteinyl leukotriene (CysLT) production and changes in CysLT production. Recent studies have reported on novel LTE4 receptor interactions and genetic polymorphisms causing CysLT variability. The applications of uLTE4 as a biomarker continue to expand, including evaluation of environmental exposures, asthma severity risk, aspirin sensitivity, predicting atopy in preschool age children, obstructive sleep apnea, and predicting susceptibility to leukotriene receptor antagonists.