Ordering RecommendationRecommendations when to order or not order the test. May include related or preferred tests.
Aid in evaluation of patient with allergic signs and symptoms, such as anaphylaxis. May assist when diagnosing and monitoring mast-cell activation disorders or when evaluating histamine production over a longer time frame.
MnemonicUnique test identifier.
NMETHYL U
MethodologyProcess(es) used to perform the test.
Quantitative Liquid Chromatography/Tandem Mass Spectrometry/Colorimetry
PerformedDays of the week the test is performed.
Varies
ReportedExpected turnaround time for a result, beginning when ARUP has received the specimen.
3-10 days
New York DOH Approval StatusIndicates test has been approved by the New York State Department of Health.
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.
Collect
24-hour urine.
Specimen Preparation
From a well-mixed 24-hour collection transfer 5 mL urine to an ARUP Standard Transport Tube. (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 or frozen.
Unacceptable Conditions
Remarks
Collection duration and urine volume must be provided for testing. Total collection volume must be greater than 500 mL.
Stability
Ambient: 2 weeks; Refrigerated: 28 days; Frozen: 28 days
Reference IntervalNormal range/expected value(s) for a specific disease state. May also include abnormal ranges.
By Report
Interpretive DataBackground information for test. May include disease information, patient result explanation, recommendations, details of testing, associated diseases, explanation of possible patient results.
CPT CodesThe American Medical Association Current Procedural Terminology (CPT) codes published in ARUP's Laboratory Test Directory are provided for informational purposes only. The codes reflect our interpretation of CPT coding requirements based upon AMA guidelines published annually. CPT codes are provided only as guidance to assist clients with billing. ARUP strongly recommends that clients confirm CPT codes with their Medicare administrative contractor, as requirements may differ. CPT coding is the sole responsibility of the billing party. ARUP Laboratories assumes no responsibility for billing errors due to reliance on the CPT codes published.
* 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.
AliasesOther names that describe the test. Synonyms.