Specimen type:  

Urine, 24-hour

Collection container:  

24 hr urine collection container, no additive

Volume:  

5 mL aliquot from a 24-hour collection

Minimum volume:  

2 mL aliquot from a 24-hour collection

Collection instructions:  

How to collect a 24 hr urine sample

Processing instructions:  

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

Transport container:  

Screw cap transfer vial/tube (Mayo T914)

Required forms/information:  

• Total volume

Transport and stability:  

Frozen (preferred) – 30 days

Refrigerated - 7 days

Ambient - 24 hours

Performing lab:  

Mayo Clinic Laboratories (TLTE4): R-NX

Days set up:  

Mo, Th

TAT:  

6 days

Method:  

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

Reference ranges:  

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

Cautions:  

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.

CPT codes:  

82542

Date created:  

03/01/2022

Revised date:  

02/06/2023

Review date:  

03/01/2022