TMAO (Trimethylamine N-Oxide)

Test Code

94154

CPT Codes
82542

Preferred Specimen

1 mL serum

Patient Preparation
Patients should fast overnight and refrain from consuming fish or other seafood the day before the blood draw to avoid false elevations in TMAO.

Minimum Volume

0.5 mL

Instructions

1. Collect and label sample according to standard protocols.
2. Gently invert tube 5 times immediately after draw. DO NOT SHAKE.
3. Allow blood to clot for 30 minutes.
4. Centrifuge for 10 minutes.
5. Store and transport refrigerated.

Transport Container

Transport tube

Transport Temperature

Refrigerated (cold packs)

Specimen Stability

Room temperature: 5 days
Refrigerated: 23 days
Frozen: 193 days

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)

Hemolysis

Methodology
Liquid Chromatography/Tandem Mass Spectrometry (LC/MS/MS)

FDA Status
This test was developed and its analytical performance characteristics have been determined by Quest Diagnostics Cardiometabolic Center of Excellence at Cleveland HeartLab. It has not been cleared or approved by the U.S. Food and Drug Administration. This assay has been validated pursuant to the CLIA regulations and is used for clinical purposes.

Setup Schedule

Set up: Mon-Sat; Report available: 6 days

Reference Range

<6.2 uM

Clinical Significance

Gut microbes live symbiotically within the human digestive tract and play important roles in host defense, immunity, and nutrient processing and absorption. The diverse community is unique to each person and influenced by both acute and chronic dietary exposures to various food sources. Nutrients such as phosphatidylcholine (also known as lecithin), choline, and L-carnitine are abundant in animal-derived products such as red meat, egg yolk and full-fat dairy products. When consumed, these nutrients are processed by gut bacteria resulting in the release of various metabolites including TMA (trimethylamine) into the blood. TMA is then transported to the liver where it is converted into TMAO (trimethylamine N-oxide) which has been shown to regulate various physiological processes involved in the development of atherosclerosis.

Performing Laboratory
Cleveland HeartLab Inc
6701 Carnegie Avenue Suite 500
Cleveland, OH 44103

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.