Test Code LAB000 N-Methylhistamine, 24 Hour, Urine (Non-Orderable)
Ordering Guidance
Random urine collection is preferred for patients with episodic symptoms, eg, in the context of allergic reactions, brought on by specific environmental factors; order NMHR / N-Methylhistamine, Random, Urine.
Specimen Required
Only orderable as part of a profile. For more information see NMH24 / N-Methylhistamine, 24 Hour, Urine.
Patient Preparation: Patients taking monoamine oxidase inhibitors (MAOIs) may have increased levels of N-methylhistamine. If medically feasible, for 2 weeks before specimen collection, patient should not take MAOIs.
Supplies: Sarstedt Aliquot Tube, 5 mL (T914)
Container/Tube: Plastic, 5-mL tube
Specimen Volume: 5 mL
Collection Instructions:
1. Collect urine for 24 hours.
2. No preservative.
3. Aliquot into plastic tube and send at refrigerate temperature.
Useful For
Only orderable as part of a profile. For more information see NMH24 / N-Methylhistamine, 24 Hour, Urine.
Screening for and monitoring of mastocytosis and disorders of systemic mast-cell activation, such as anaphylaxis and other forms of severe systemic allergic reactions as a part of a profile
Monitoring therapeutic progress in conditions that are associated with secondary, localized, low-grade persistent, mast-cell proliferation and activation such as interstitial cystitis
Method Name
Only orderable as part of a profile. For more information see NMH24 / N-Methylhistamine, 24 Hour, Urine.
Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS)
Reporting Name
N-Methylhistamine, 24 Hr, USpecimen Type
UrineSpecimen Stability Information
| Specimen Type | Temperature | Time |
|---|---|---|
| Urine | Refrigerated (preferred) | 28 days |
| Frozen | 28 days | |
| Ambient | 14 days |
Reject Due To
All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.Reference Values
Only orderable as part of a profile. For more information see NMH24 / N-Methylhistamine, 24 Hour, Urine.
0-5 years: 85-369 mcg/g creatinine
6-16 years: 48-238 mcg/g creatinine
>16 years: 19-143 mcg/g creatinine
Day(s) Performed
Monday, Wednesday, Friday
Performing Laboratory
Mayo Clinic Laboratories in Rochester
Test Classification
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
82542
LOINC Code Information
| Test ID | Test Order Name | Order LOINC Value |
|---|---|---|
| NMH1D | N-Methylhistamine, 24 Hr, U | 44340-8 |
| Result ID | Test Result Name | Result LOINC Value |
|---|---|---|
| 605159 | N-Methylhistamine, 24 Hr | 44340-8 |
Report Available
3 to 7 daysSpecimen Minimum Volume
3 mL