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
NMETH RAN
Methodology

Quantitative Liquid Chromatography/Tandem Mass Spectrometry/Colorimetry

Performed

Varies

Reported

3-10 days

New York DOH Approval Status
This test is New York DOH approved.
Specimen Required
Patient Preparation

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.

Collect

Urine

Specimen Preparation

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.

Storage/Transport Temperature

Refrigerated. Also acceptable: Room temperature and frozen.

Unacceptable Conditions
Remarks
Stability

Ambient: 2 weeks; Refrigerated: 28 days; Frozen: 28 days

Reference Interval

By Report

Interpretive Data



Compliance Category

Performed by non-ARUP Laboratory

Note
Hotline History
N/A
CPT Codes

82542, 82570

Components
Component Test Code* Component Chart Name LOINC
3002744 N-Methylhistamine, Random Urine
3002745 Creatinine Concentration, Random Urine
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.
Aliases
  • 1-Methylhistamine
  • Histamine Metabolites
  • Urinary N-Methylhistamine
N-Methylhistamine, Random Urine

Mayo Clinic Laboratories