Leukotriene E4, 24-hour urine
Leukotriene E4, 24-hour urine-994
7/29/2026 - This test is unavailable for the next 3+ weeks due to an instrument issue at the performing lab. There is no alterative test available.
Leukotriene E4, 24-hour urine
994
LAB994
MSO
Cysteinyl Leukotriene
LTE4
Mast Cell Activation Syndrome
Mastocytosis
Systemic Mast Cell Activation
Idiopathic MCAS
LTE4
Mast Cell Activation Syndrome
Mastocytosis
Systemic Mast Cell Activation
Idiopathic MCAS
Aiding in the evaluation of patients at-risk for mast cell activation syndrome (eg, systemic mastocytosis, IgE-mediated allergies, or aspirin-exacerbated respiratory disease) using 24-hour urine collections
Patient should not take zileuton for 48 hours before specimen collection
Urine, 24-hour
5 mL aliquot from a 24-hour collection
2 mL aliquot from a 24-hour collection
- Measure and record total urine volume
- Include the total volume on the request form
- Mix well
- Transfer a 5 mL (minimum 2.0mL) aliquot to a Screw cap transfer vial/tube (Mayo T914), labeled as urine
- Freeze
- Collection duration
- Total volume
Frozen (preferred) – 28 days
Refrigerated - 7 days
Ambient - 24 hours
Mayo Clinic Laboratories (TLTE4): R-NX
Mo, Tu, Th
2 - 9 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
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.
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.
82542
03/01/2022
07/31/2026
07/31/2026