Liquid Chromatography Tandem Mass Spectrometry.
In conjunction or as an alternative to 5-HIAA or serum chromogranin A measurements as a first line test in the diagnosis of carcinoid syndrome.
<= 330 ng/mL
Medications that may affect serotonin concentrations include lithium, MAO inhibitors, methyldopa, morphine, and reserpine.
2 - 8 days
- Hydroxytryptamine, 5-
- SEROTONIN, WHOLE BLOOD
Collect specimen in a lavender top tube. Transfer 2.5 mL of whole blood into Serotonin Whole Blood Transport tube (contains 20 mg ascorbic acid), mix well and freeze immediately. Do not over or under fill tubes.
The preferred sample for measurement of serotonin includes all or most of the platelets (i.e., whole blood) or serum from completely clotted specimens. Serotonin- or tryptophan-rich foods (avocados, bananas, plums, walnuts, pineapple, eggplant, plantain, tomatoes, hickory nuts, kiwi, dates, grapefruit, cantaloupe, and honeydew melon) do not contribute significantly to serum or blood serotonin measurements, but can elevate platelet-poor plasma serotonin, urinary serotonin, and urinary 5-HIAA levels markedly (up to 10-fold). Test sent to Mayo Medical Laboratories.