Abstract
Cysteinyl leukotrienes (CysLTs: leukotrienes C4, D4, and E4) have long been implicated in the pathogenesis of asthma and several allergic diseases. LTE4 has been identified as a major metabolite of LTC4, and urinary LTE4 (U-LTE4) is considered as the most reliable analytic parameter for monitoring the endogenous synthesis of CysLTs. From recent studies on the U-LTE4 associated with adult stable asthma we identified four factors for hyperleukotrieneuria, namely, aspirin intolerance, eosinophilic nasal polyposis (ENP), vasculitis, and severe asthma. In ENP, there is prominent infiltration of eosinophils in the sinus and polyp tissues, which is linked to adult asthma and aspirin sensitivity, and ENP is the most important factor for the overproduction of CysLTs in asthmatics. We also demonstrated that anaphylaxis and eosinophilic pneumonia (EP) are associated with a marked increase in the U-LTE4 concentration. Under these disease conditions, U-LTE4 may be one of the candidate biomarkers. Moreover, the changes in U-LTE4 concentrations may provide valuable information concerning therapeutic targets.
