Please login to order a test.
This assay is not approved for patients of New York State physicians.
For more information, please view the literature below.
Serum, shipped refrigerated (preferred)
NMR LipoTube (black-and-yellow-top tube)
For NMR LipoTube (black-and-yellow-top tube), keep upright at room temperature for 30 minutes and allow to clot. Centrifuge at 1800 to 2200g for 10 to 15 minutes immediately after clotting. If the sample cannot be centrifuged immediately, it must be refrigerated at (2°C to 8°C) and centrifuged within 24 hours of collection. The NMR tube should then be stored at (2°C to 8°C) until shipped. Do not open NMR LipoTube. Serum or plasma drawn in gel-barrier collection tubes other than the NMR LipoTube should not be used.
TMAO levels are lower in humans who follow a vegetarian or vegan diet than in omnivores.3 Because TMA and TMAO are naturally abundant in some fish,7,8 patients should fast overnight and refrain from consuming fish and other marine food items the day before the blood draw. Fasting for 10 to 12 hours is recommended.
Causes for Rejection
Unspun LipoTube; serum specimen drawn in gel-barrier collection tube other than the NMR LipoTube
High levels of TMAO have been associated with an increased risk of heart disease.1
The TMAO test may be used as (1) an aid in the assessment of risk for cardiovascular disease (CVD), independent of established risk factors, (2) an aid in the determination of altered gut microbiome (gut dysbiosis) in individuals who may benefit from intensive dietary intervention, and (3) a monitor therapy aimed at reducing TMAO concentrations.
This test was developed and its performance characteristics determined by LabCorp. It has not been cleared or approved by the Food and Drug Administration.
Nuclear magnetic resonance (NMR)
TMAO is a dietary metabolite produced by a pathway involving gut microbiota. TMAO concentrations increase in the blood after ingestion of dietary choline and L-carnitine, which are abundant in meat, eggs, liver, and wheat germ and energy drinks. Choline and L-carnitine are metabolized in the gut by microbiota to form trimethylamine (TMA), which is subsequently oxidized in the liver into TMAO by flavin monooxygenases (FMOs). TMAO concentrations have been shown to be reduced in animals and humans treated with broad-spectrum oral antibiotics confirming the requirement for gut bacteria in the formation of TMA and TMAO.2-6 TMAO has been hypothesized to promote atherosclerosis by upregulating macro-phage scavenger receptor activity and downregulating bile acid synthesis which together reduce reverse cholesterol transport.2-6