Sign in →

Test ID NMH24 N-Methylhistamine, 24 Hour, Urine


Advisory Information


Random urine collections are preferred for patients with episodic symptoms, for example in the context of allergic reactions, brought on by specific environmental factors. See NMHR / N-Methylhistamine, Random, Urine.



Specimen Required


Patient Preparation: Patient must not be taking monoamine oxidase inhibitors (MAOIs) or aminoguanidine as these medications increase N-methylhistamine (NMH) levels.

Supplies: Aliquot Tube, 5 mL

Container/Tube: Plastic, 5-mL tube

Specimen Volume: 5 mL

Collection Instructions:

1. Collect urine for 24 hours.

2. No preservative.

Additional Information: See Urine Preservatives-Collection and Transportation for 24-Hour Urine Specimens in Special Instructions for multiple collections.


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 using 24-hour urine collection specimens

 

Monitoring therapeutic progress in conditions that are associated with secondary, localized, low-grade persistent, mast-cell proliferation and activation such as interstitial cystitis

Profile Information

Test ID Reporting Name Available Separately Always Performed
NMH1D N-Methylhistamine, 24 Hr, U No Yes
CRT24 Creatinine, 24 Hour, U No Yes

Method Name

NMH1D: Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)

CRT24: Enzymatic Colorimetric Assay

Reporting Name

N-Methylhistamine, 24 Hr, U

Specimen Type

Urine

Specimen Minimum Volume

3 mL

Specimen Stability Information

Specimen Type Temperature Time Special Container
Urine Refrigerated (preferred) 28 days
  Ambient  28 days
  Frozen  28 days

Reference Values

0-5 years: 120-510 mcg/g creatinine

6-16 years: 70-330 mcg/g creatinine

>16 years: 30-200 mcg/g creatinine

Day(s) and Time(s) Performed

Tuesday, Thursday; 10 a.m.

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. This test has not been cleared or approved by the U.S. Food and Drug Administration.

CPT Code Information

82542

LOINC Code Information

Test ID Test Order Name Order LOINC Value
NMH24 N-Methylhistamine, 24 Hr, U 44340-8

 

Result ID Test Result Name Result LOINC Value
CR_A Creatinine, 24 Hour, U 2162-6
605159 N-Methylhistamine, 24 Hr 44340-8
TM10 Collection Duration 13362-9
VL8 Urine Volume 3167-4
CR_24 Creatinine Concentration, 24 Hr, U 20624-3

NY State Approved

Yes

Urine Preservative Collection Options

Note: The addition of preservative or application of temperature controls must occur within 4 hours of completion of the collection.

Ambient

OK

Refrigerate

Preferred

Frozen

OK

50% Acetic Acid

OK

Boric Acid

OK

Diazolidinyl Urea

No

6M Hydrochloric Acid

OK

6M Nitric Acid

OK

Sodium Carbonate

OK

Thymol

No

Toluene

No