Order Code NMH1D N-Methylhistamine, 24 Hour, Urine
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: Patient must not be taking monoamine oxidase inhibitors (MAOIs) or aminoguanidine as these medications increase N-methylhistamine (NMH) levels.
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
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 | Special Container |
---|---|---|---|
Urine | Refrigerated (preferred) | 28 days | |
Ambient | 28 days | ||
Frozen | 28 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: 120-510 mcg/g creatinine
6-16 years: 70-330 mcg/g creatinine
>16 years: 30-200 mcg/g creatinine
Method Description
N-methylhistamine (NMH) is removed from urine using solid phase extraction. The eluate is analyzed using liquid chromatography/tandem mass spectrometry and quantified using a stable isotope labeled internal standard, d3-NMH. NMH and d3-NMH are detected in multiple reaction monitoring mode using the specific transitions for m/z 126 to m/z 109, and m/z 129 to m/z 112, respectively.(Unpublished Mayo method)
Day(s) Performed
Monday, Wednesday, Friday
Performing Laboratory
Mayo Clinic Laboratories in RochesterCPT Code Information
82542
Specimen Minimum Volume
3 mL