5-Hydroxyindoleacetic Acid, Plasma
Use
This test is useful for the biochemical diagnosis and monitoring of intestinal carcinoid syndrome using a plasma specimen. It measures the levels of 5-HIAA, a serotonin metabolite often associated with neuroendocrine tumors, providing valuable insight into the presence and progression of the disease.
Special Instructions
Patient's age is required. It is important to avoid certain foods and medications prior to collecting the specimen to prevent interference with test results. Use Sarstedt Aliquot Tube, 5 mL (T914) for submitting samples.
Limitations
Numerous foods and medications can interfere with test results, potentially causing false elevations in 5-HIAA levels. Foods high in serotonin, such as nuts and fruit, should be avoided. Medications like acetaminophen and tryptophan-containing supplements can also alter results if not managed properly around the time of collection.
New York Approved
Methodology
Mass Spectrometry (LC-MS/MS)
Biomarkers
LOINC Codes
- 1693-1
- 1693-1
Result Turnaround Time
2-4 days
Related Documents
For more information, please review the documents below
Specimen
Plasma
Volume
0.5 mL
Minimum Volume
0.2 mL
Container
Green top (sodium heparin); Lavender top (EDTA); Plastic vial for submission
Collection Instructions
Centrifuge at 4 degrees C. Aliquot plasma into plastic vial and send frozen.
Patient Preparation
Avoid medications like acetaminophen and tryptophan supplements for 48 hours before and during collection. Limit fruit, vegetables, and caffeinated items to one serving per day and avoid nuts, especially walnuts, for 24 hours prior to collection.
Causes for Rejection
Warm thawing
Stability Requirements
| Temperature | Period |
|---|---|
| Refrigerated | 72 hours |
| Frozen | 60 days |