5‑Hydroxyindoleacetic Acid, Random, Urine
Use
Measurement of 5‑HIAA in a random urine specimen can diagnose carcinoid disease with a high specificity. 5‑Hydroxyindoleacetic acid (5‑HIAA) is the major metabolite of serotonin and is excreted in the urine. Intestinal carcinoid tumors and neuroendocrine tumors can produce excess amounts of serotonin and 5‑HIAA, particularly in individuals with carcinoid syndrome, which may present with flushing, heart disease, and hepatomegaly. This test supports biochemical diagnosis and monitoring of intestinal carcinoid syndrome using random urine specimens.
Special Instructions
Patient’s age and sex are required. Some medications (e.g., acetaminophen, tryptophan supplements) and dietary items (fruits, vegetables, nuts, caffeinated beverages/foods) should be avoided for 48 hours before collection. Supplies: 10 mL plastic urine tube (T068). Collect a random urine specimen, store and send refrigerated. If a 24‑hour urine collection is preferred, order HIAA / 5‑Hydroxyindoleacetic Acid, 24 Hour, Urine.
Limitations
An elevated 5‑HIAA excretion is a probable indicator of a serotonin‑producing tumor if pharmacological and dietary artifacts have been ruled out. Specimen suitability is evaluated by Mayo Clinic Laboratories; improper collection or interference from certain foods or medications may affect results. Reference intervals vary by age and sex.
New York Approved
Methodology
Mass Spectrometry (LC‑MS/MS)
Biomarkers
LOINC Codes
- 11145-0
- 11145-0
Result Turnaround Time
2-4 days
Related Documents
For more information, please review the documents below
Specimen
Urine
Volume
5 mL
Minimum Volume
2 mL
Container
Plastic, 10‑mL urine tube
Collection Instructions
Collect a random urine specimen. Store and send refrigerated.
Patient Preparation
Avoid acetaminophen, tryptophan supplements and limit fruits, vegetables, nuts, and caffeinated foods/beverages for 48 hours prior.
Causes for Rejection
All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.
Stability Requirements
| Temperature | Period |
|---|---|
| Refrigerated | 56 days |
| Frozen | 365 days |