An aid to evaluate patients suspected of having systemic mastocytosis Identification of aspirin sensitivity in patient respiratory diagnoses
Patients taking 5-lipoxygenase inhibitor Zileuton/Zyflo may have decreased concentrations of leukotriene E4 (LTE4) if dosage has not been discontinued for 48 hours. If possible, discontinue for 48 hours before testing.
Transfer 4 mL of random urine to a Screw cap transfer vial/tube (Mayo T465)
Refrigerated (preferred) - 7 days
Frozen - 30 days
Ambient - 24 hours
Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)
≤ 104 pg/mg creatinine