5-Hydroxyindoleacetic Acid (5-HIAA), 24-Hour Urine with Creatinine : 1015172

Test Code
U5H24Q or 1015172

Alias/See Also
5-Hydroxyindoleacetic Acid , Serotonin Metabolite

CPT Codes
83497, 82570

Instructions
Patient should avoid food high in indoles: avocados, banana, tomato, plum, walnut, pineapple, and eggplant.

Collect 24-hour urine. Keep urine refrigerated during and after collection.

Transport Container
Transport 10 mL aliquot from a well-mixed 24-hour collection, (Min: 5 mL).  Keep refrigerated. Record  24-hour total volume on transport container and test request form.
  
If transported to the laboratory on the same day of the completion of collection, transport refrigerated.
  
If transport is delayed beyond 24 hours of completion of collection, see below alternate processing/transportation instructions:
        A. After urine collection, add 6N HCl to maintain a pH < or = 3. Transport 10 mL aliquot of  pH adjusted  ( < or = pH 3) urine, refrigerated.
          OR
       B.  If 6N HCL is not available and urine pH is < or = 6, freeze  10 mL aliquot of urine and transport frozen.

Transport Temperature
Refrigerated or Frozen.

Specimen Stability
Keep refrigerated during collection. Transport ASAP.
   
After preservation with 6 N HCL to pH < or = 3:  Ambient: 7 days; Refrigerated: 30  days; Frozen: 30 days        Unpreserved Urine with pH  < or = 6 : Frozen 30 days  

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)
Preserved urine received refrigerated with pH > 3; Unpreserved urine received frozen with pH > 6.

Methodology
High Performance Liquid Chromatography, Electrochemical Detection

Setup Schedule
Tuesday & Thursday & Friday

Report Available
3-7 days (From receipt at performing laboratory)

Limitations
.

Reference Range
2-10 yrs: less than or equal to 8.0 mg/24 h
>10 yrs: less than or equal to 6.0 mg/24 h

Clinical Significance
5-HIAA is the end product of serotonin (5-hydroxytryptophan) and tyrptophan metabolism. Patients with carcinoid tumors of the midgut, e.g., ileum, produce high concentrations of 5-HIAA. Patients with carcinoid tumors of the foregut and hindgut may produce little or no 5-HIAA or do so intermittently.

Performing Laboratory
Quest Diagnostics



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.