Test Directory

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 random urine collections.

Specimen Type: Random Urine

Collection Container: Sterile Container

Desired Specimen Volume: 5 mL

1. Collect specimen within a few hours of symptom onset.
2. Collect urine in sterile container.

1. Transport urine in the original collection container or transfer 5 mL of urine to clear aliquot tubes (screw cap).
2. For an optimal evaluation, testing for urinary leukotriene E4 should be accompanied by laboratory investigations for the presence of serum tryptase, urinary 2,3-dinor 11 beta-prostaglandin F2 alpha and urinary N-methylhistamine.

Patients taking 5-lipoxygenase inhibitor zileuton (Zyflo) may have decreased concentrations of leukotriene E4 (LTE4). If medically feasible, the patient should not take zileuton for 48 hours before specimen collection.

Transport to the laboratory refrigerated. 

See patient report.

Results should be interpreted in conjunction with the patient's clinical presentation and other laboratory findings.

This assay measures both LTE4 and the 11-trans-LTE4 as markers of MC release.