N-Methylhistamine, 24 Hour, Urine
Additional Codes
LAB3887
Ordering Guidance
Random urine collections are 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.
If the total volume provided is less than 300 mL, this test will be canceled and NMHR ordered and performed.
Necessary Information
Specimen volume (in milliliters) and duration are required.
Specimen Required
Patient Preparation: Patients taking monoamine oxidase inhibitors (MAOIs) may have increased levels of N-methylhistamine. If medically feasible, for 2 weeks before specimen collection, patient should not take MAOIs.
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.
Additional Information: See Urine Preservatives-Collection and Transportation for 24-Hour Urine Specimens for multiple collections.
Profile Information
| Test ID | Reporting Name | Available Separately | Always Performed |
|---|---|---|---|
| NMH1D | N-Methylhistamine, 24 Hr, U | No | Yes |
| CRT24 | Creatinine, 24 HR, U | No | Yes |
Special Instructions
Specimen Type
UrineSpecimen Minimum Volume
3 mL
Specimen Stability Information
| Specimen Type | Temperature | Time |
|---|---|---|
| Urine | Refrigerated (preferred) | 28 days |
| Frozen | 28 days | |
| Ambient | 14 days |
Reference Values
N-METHYLHISTAMINE
0-5 years: 85-369 mcg/g creatinine
6-16 years: 48-238 mcg/g creatinine
>16 years: 19-143 mcg/g creatinine
CREATININE
Males: 930-2955 mg/24 hours
Females: 603-1783 mg/24 hours
Reference values have not been established for patients who are younger than 18 years.
Day(s) Performed
Monday, Wednesday, Friday
Report Available
3 to 7 daysSpecimen Retention Time
14 daysPerforming Laboratory
Mayo Clinic Laboratories in Rochester
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 HR, U | 2162-6 |
| 605159 | N-Methylhistamine, 24 Hr | 44340-8 |
| TM27 | Collection Duration (h) | 13362-9 |
| VL69 | Urine Volume (mL) | 3167-4 |
| CR_24 | Creatinine Concentration, 24 HR, U | 20624-3 |