Ordering Recommendation
Aid in evaluation of patient with allergic signs and symptoms, such as anaphylaxis and other forms of severe systemic allergic reactions. May assist when diagnosing and monitoring mast-cell activation disorders or when evaluating histamine production over a longer time frame. Patients with chronic mast-cell activation often have chronically elevated N-methylhistamine (NMH) levels and will sometimes have intermittent NMH elevations. In these cases, N-Methylhistamine, 24-Hour Urine (2011034) is preferred.
Mnemonic
Methodology
Quantitative Liquid Chromatography-Tandem Mass Spectrometry/Colorimetry
Performed
Varies
Reported
3-10 days
New York DOH Approval Status
Specimen Required
Patient must not be taking monoamine oxidase inhibitors (MAOIs) or aminoguanidine as these medications increase N-methylhistamine (NMH) levels. Specimen should be collected within a few hours of symptom onset.
Urine
Transfer 5 mL urine to ARUP Standard Transport Tubes. (Min: 3 mL)
Test is not performed at ARUP; separate specimens must be submitted when multiple tests are ordered.
Refrigerated. Also acceptable: Room temperature and frozen.
Ambient: 2 weeks; Refrigerated: 28 days; Frozen: 28 days
Reference Interval
By Report
Interpretive Data
Performed by non-ARUP Laboratory
Note
Hotline History
CPT Codes
82542, 82570
Components
Component Test Code* | Component Chart Name | LOINC |
---|---|---|
3002744 | N-Methylhistamine, Random Urine | |
3002745 | Creatinine Concentration, Random Urine |
Aliases
- 1-Methylhistamine
- Histamine Metabolites
- Urinary N-Methylhistamine
Mayo Clinic Laboratories