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HelpTest Code MCM24 Mast Cell Mediators, 24 Hour, Urine
Ordering Guidance
Random urine collections are preferred for patients with episodic symptoms, for example in the context of allergic reactions brought on by specific environmental factors. For random urine collections, order MCMRU / Mast Cell Mediators, Random, Urine.
Specimen Required
Patient Preparation:
1. Patient must not be taking monoamine oxidase inhibitors (MAOI) or aminoguanidine, as these medications increase N-methylhistamine (NMH) levels.
2. Patients taking aspirin or nonsteroidal anti-inflammatory drugs (NSAID) may have decreased concentrations of prostaglandin F2 alpha (23BP). If possible, the patient should discontinue use for 2 weeks or 72 hours, respectively, before specimen collection.
Supplies: Urine Container, 60 mL (T313)
Collection Container/Tube: Plastic urine container
Submission Container/Tube: Plastic, 60-mL urine bottle
Specimen Volume: 20 mL
Collection Instructions:
1. Collect urine for 24 hours.
2. No preservative.
3. Aliquot urine into plastic tube and send to lab.
Additional Information: See Urine Preservatives-Collection and Transportation for 24-Hour Urine Specimens for multiple collections.
Secondary ID
608378Useful For
Evaluating patients at risk for mast cell activation syndrome (eg, systemic mastocytosis) using 24-hour urine collections
Profile Information
| Test ID | Reporting Name | Available Separately | Always Performed |
|---|---|---|---|
| CRT2F | Creatinine, 24 HR, U | No | Yes |
| TLTE1 | Leukotriene E4, 24 Hr, U | Yes | Yes |
| T23B1 | 2,3-dinor 11B-Prostaglandin F2a | Yes | Yes |
| TNMH1 | N-Methylhistamine, 24 Hr, U | Yes | Yes |
Special Instructions
Method Name
CRT2F: Enzymatic Colorimetric Assay
TLTE1, T23B1, TNMH1: Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS)
Specimen Type
UrineSpecimen Minimum Volume
10 mL
Specimen Stability Information
| Specimen Type | Temperature | Time | Special Container |
|---|---|---|---|
| Urine | Frozen | 28 days |
Reject Due To
All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.Reference Values
N-METHYLHISTAMINE:
0-5 years: 120-510 mcg/g creatinine
6-16 years: 70-330 mcg/g creatinine
>16 years: 30-200 mcg/g creatinine
2,3-DINOR 11B-PROSTAGLANDIN F2a:
<1802 pg/mg creatinine
LEUKOTRIENE E4:
≤104 pg/mg creatinine
CREATININE:
Males: 930-2955 mg/24 h
Females: 603-1783 mg/24 h
Reference values have not been established for patients who are younger than 18 years.
Interpretation
Analytical reports within the scope of the individual assays will be provided when testing is complete.
Method Description
N-methylhistamine is extracted from urine using solid-phase extraction. The elute is analyzed using liquid chromatography tandem mass spectrometry (LC-MS/MS) and quantified using a stable isotope labeled internal standard.(Martens-Lobenhoffer J, Neumann HJ. Determination of 1-methylhistamine and 1-methylimidazoleacetic acid in human urine as a tool for the diagnosis of mastocytosis. J Chromatogr B Biomed Sci Appl. 1999;721[1]:135-140; Lueke AJ, Meeusen JW, Donato LJ, Gray AV, Butterfield JH, Saenger AK. Analytical and clinical validation of an LC-MS/MS method for urine leukotriene E4: A marker of systemic mastocytosis. Clin Biochem. 2016;49[13-14]:979-982. doi:10.1016/j.clinbiochem.2016.02.007)
2,3-Dinor-11beta-prostaglandin F2alpha:
2,3-Dinor-11beta-prostaglandin F2alpha (23BPG) is quantified in urine by LC-MS/MS. Deuterium-labeled 23BPG internal standard (d4-11BPGF2a) is added to all controls and specimens, which are then liquid/liquid extracted. The eluent is evaporated, and samples/QC are then reconstituted prior to LC-MS/MS analysis.(Unpublished Mayo method)
Leukotriene E4:
Leukotriene E4 (LTE4) is quantified in urine via multiplexed LC-MS/MS. Deuterium-labeled LTE4 internal standard is added to all standards/controls/samples, which are then filtered. After additional sample clean-up, this eluent is analyzed by LC-MS/MS.(Unpublished Mayo method)
Creatinine:
The enzymatic method is based on the determination of sarcosine from creatinine with the aid of creatininase, creatinase, and sarcosine oxidase. The liberated hydrogen peroxide is measured via a modified Trinder reaction using a colorimetric indicator. Optimization of the buffer system and the colorimetric indicator enables the creatinine concentration to be quantified both precisely and specifically.(Package insert: Creatinine plus ver 2. Roche Diagnostics; V15.0, 03/2019)
Day(s) Performed
Monday, Tuesday, Thursday
Report Available
3 to 7 daysSpecimen Retention Time
See individual Test IDsPerforming Laboratory
Mayo Clinic Laboratories in Rochester
CPT Code Information
82542
84150
LOINC Code Information
| Test ID | Test Order Name | Order LOINC Value |
|---|---|---|
| MCM24 | Mast Cell Mediators, 24 Hour, U | In Process |
| Result ID | Test Result Name | Result LOINC Value |
|---|---|---|
| CR_AF | Creatinine, 24 HR, U | 2162-6 |
| 620242 | 2,3-dinor 11B-Prostaglandin F2a | 94381-1 |
| 620244 | N-Methylhistamine, 24 Hr | 44340-8 |
| 620240 | Leukotriene E4, U | 101115-4 |
| TM10F | Collection Duration (h) | 13362-9 |
| VL8F | Urine Volume (mL) | 3167-4 |
| CRF24 | Creatinine Concentration, 24 HR, U | 20624-3 |