Leukotriene E4, 24-hour urine

Alphabetical Test listing

Leukotriene E4, 24-hour urine-994

Leukotriene E4, 24-hour urine
Cysteinyl Leukotriene
Mast Cell Activation Syndrome
Systemic Mast Cell Activation

An aid to evaluate patients suspected of having systemic mastocytosis using 24-hour urine collections

Urine, 24-hour
5 mL aliquot from a 24-hour collection
2 mL aliquot from a 24-hour collection
  1. Measure and record total urine volume
  2. Include the total volume on the request form
  3. Mix well
  4. Transfer a 5 mL (minimum 2.0mL) aliquot to a Screw cap transfer vial/tube (Mayo T914), labeled as urine
  • Total volume

Frozen (preferred) – 30 days

Refrigerated - 7 days

Ambient - 24 hours

Mayo Clinic Laboratories (TLTE4): R-NX
Mo, Th
6 days

Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS), Enzymatic Colorimetric Assay


Leukotriene E4:

≤104 pg/mg creatinine

Creatinine (Normal values mg per 24 hours):

Male: 930 - 2955 mg/24 hours

Female: 603 - 1783 mg/24 hours

Patients taking 5-lipoxygenase inhibitor zileuton/Zyflo may have decreased concentrations of leukotriene E4 (LTE4) if dosage has not been discontinued for 48 hours.

Systemic mastocytosis is a heterogenous disease and lack of elevated LTE4 does not exclude the diagnosis of mast cell disease.

Increased excretion of LTE4 has also been reported in the following conditions: asthma, eosinophilic pneumonia, respiratory syncytial virus infection, atopic dermatitis, Crohn disease, and rheumatoid arthritis.