TEST CATALOG ORDERING & RESULTS SPECIMEN HANDLING CUSTOMER SERVICE EDUCATION & INSIGHTS
Test Catalog

Test ID: NMH24    
N-Methylhistamine, 24 Hour, Urine

Specimen Type Describes the specimen type validated for testing

Urine

Ordering Guidance

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 Defines the optimal specimen required to perform the test and the preferred volume to complete testing

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 (T465)

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.

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

Special Instructions Library of PDFs including pertinent information and forms related to the test

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

Specimen Minimum Volume Defines the amount of sample necessary to provide a clinically relevant result as determined by the Testing Laboratory

3 mL

Reject Due To Identifies specimen types and conditions that may cause the specimen to be rejected

All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.

Specimen Stability Information Provides a description of the temperatures required to transport a specimen to the performing laboratory, alternate acceptable temperatures are also included

Specimen TypeTemperatureTimeSpecial Container
UrineRefrigerated (preferred)28 days
 Frozen 28 days
 Ambient 14 days