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26096 5-Hydroxyindoleacetic Acid 24 Hr U (HIAA)

5-Hydroxyindoleacetic Acid 24 Hr U (HIAA)
Test Code: HIAASO
Synonyms/Keywords
​5-HIAA, HIAA,  5-OH-Indoleacetic Acid, Carcinoid Syndrome, Hydroxyindoleacetic Acid, Serotonin Metabolite
Useful For
Biochemical diagnosis and monitoring of intestinal carcinoid syndrome
Specimen Requirements
Fasting Required Specimen Type Preferred Container/Tube Acceptable Container/Tube Specimen Volume Specimen Minimum Volume
(allows for 1 repeat)		 Pediatric Minimum Volume
(no repeat)
​*Dietary Restrictions and Drug Interactions ​Urine ​10 mL Urine Tube ​Plastic Urine Container ​10 mL ​5 mL ​1 mL
Collection Processing Instructions

*Intake of food with a high content of serotonin (avocados, dates, eggplant, all fruit [including bananas, cantaloupe, grapefruit, kiwifruit, melons, pineapple, plantains, plums], all nuts [including hickory nuts, butternuts, pecans, walnuts], and tomatoes and tomato products) within 48 hours of the urine collection could result in falsely elevated 5-hydroxyindoleacetic acid (5-HIAA) excretion.

Numerous drugs affect the excretion of 5-HIAA by different mechanisms, including increased serotonin synthesis, metabolism, and release and inhibition of uptake. The following medications can interfere with 5-HIAA results. If clinically feasible, discontinue the following medications at least 48 hours before specimen collection.
-Acetaminophen (Tylenol or generic versions)
-Aspirin
-Antihistamines
-Cough syrups
-Cold and flu medications

Patient should also avoid caffeinated beverages such as tea and coffee or caffeinated foods for 48 hours before and during the 24 hour specimen collection.

Collection Procession Instructions:
1. Collect a 24-hour urine specimen.
2. Add 25 mL of 50% acetic acid as preservative at start of collection. Use 15 mL of 50% acetic acid for children <5 years old.
Urine Preservatives-Collection and Transportation for 24-Hour Urine Specimens

Specimen Stability Information
Specimen Type Temperature Time
​Urine ​ ​Refrigerate (preferred) ​56 days
​Frozen ​365 days
Rejection Criteria
Ambient Urine Samples
Interference
Numerous drugs affect the excretion of 5-HIAA by different mechanisms, including increased serotonin synthesis, metabolism, and release and inhibition of uptake. The following medications can interfere with 5-HIAA results. If clinically feasible, discontinue the following medications at least 48 hours before specimen collection.
-Acetaminophen (Tylenol or generic versions)
-Aspirin
-Antihistamines
-Cough syrups
-Cold and flu medications
Performing Laboratory Information
Performing Location Day(s) Test Performed Analytical Time Methodology/Instrumentation
​Mayo Medical Laboratories ​Monday through Thursday; 11 a.m.;
Friday: 2 p.m.		 ​2 days (not reported on Saturdays or Sundays) ​Solid Phase Extraction (SPE) and Liquid Chromatography/Tandem Mass Spectrometry (LC/MS/MS) analysis
Reference Lab
Mayo Clinic Laboratories
Test Information
This test was developed and its performance characteristics determined by Mayo Medical Laboratories.
 
5-Hydroxyindoleacetic acid (5-HIAA) is the major metabolite of serotonin and is excreted in the urine. Intestinal carcinoid tumors along with neuroendocrine tumors can produce excess amounts of 5-HIAA and serotonin especially in individuals with carcinoid syndrome. Carcinoid syndrome is characterized by carcinoid tumors, flushing, heart disease, and hepatomegaly. 
Measurement of 5-HIAA in a 24-hour urine specimen can diagnose carcinoid disease with a high specificity.
Reference Range Information
Performing Location Reference Range
​Mayo Medical Laboratories ​<=8 mg/24 hours
Interpretation
Elevated excretion of 5-hydroxyindoleacetic acid is a probable indicator of the presence of a serotonin-producing tumor, if pharmacological and dietary artifacts have been ruled out.
Outreach CPTs
CPT Modifier
(if needed)		 Quantity Description Comments
​83497 ​ ​1 ​ ​
Classification
This test was developed and its performance characteristics determined by Mayo Medical Laboratories.
Synonyms/Keywords
​5-HIAA, HIAA,  5-OH-Indoleacetic Acid, Carcinoid Syndrome, Hydroxyindoleacetic Acid, Serotonin Metabolite
Ordering Applications
Ordering Application Description
​Centricity ​5-Hydroxyindoleacetic Acid 24 Hr U (HIAA)
​Cerner ​5-Hydroxyindoleacetic Acid 24 Hr U (HIAA)
​COM ​5-Hydroxyindoleacetic Acid 24 Hr U (HIAA)
If the ordering application you are looking for is not listed, contact your local laboratory for assistance.
Specimen Requirements
Fasting Required Specimen Type Preferred Container/Tube Acceptable Container/Tube Specimen Volume Specimen Minimum Volume
(allows for 1 repeat)		 Pediatric Minimum Volume
(no repeat)
​*Dietary Restrictions and Drug Interactions ​Urine ​10 mL Urine Tube ​Plastic Urine Container ​10 mL ​5 mL ​1 mL
Collection Processing

*Intake of food with a high content of serotonin (avocados, dates, eggplant, all fruit [including bananas, cantaloupe, grapefruit, kiwifruit, melons, pineapple, plantains, plums], all nuts [including hickory nuts, butternuts, pecans, walnuts], and tomatoes and tomato products) within 48 hours of the urine collection could result in falsely elevated 5-hydroxyindoleacetic acid (5-HIAA) excretion.

Numerous drugs affect the excretion of 5-HIAA by different mechanisms, including increased serotonin synthesis, metabolism, and release and inhibition of uptake. The following medications can interfere with 5-HIAA results. If clinically feasible, discontinue the following medications at least 48 hours before specimen collection.
-Acetaminophen (Tylenol or generic versions)
-Aspirin
-Antihistamines
-Cough syrups
-Cold and flu medications

Patient should also avoid caffeinated beverages such as tea and coffee or caffeinated foods for 48 hours before and during the 24 hour specimen collection.

Collection Procession Instructions:
1. Collect a 24-hour urine specimen.
2. Add 25 mL of 50% acetic acid as preservative at start of collection. Use 15 mL of 50% acetic acid for children <5 years old.
Urine Preservatives-Collection and Transportation for 24-Hour Urine Specimens

Specimen Stability Information
Specimen Type Temperature Time
​Urine ​ ​Refrigerate (preferred) ​56 days
​Frozen ​365 days
Rejection Criteria
Ambient Urine Samples
Interference
Numerous drugs affect the excretion of 5-HIAA by different mechanisms, including increased serotonin synthesis, metabolism, and release and inhibition of uptake. The following medications can interfere with 5-HIAA results. If clinically feasible, discontinue the following medications at least 48 hours before specimen collection.
-Acetaminophen (Tylenol or generic versions)
-Aspirin
-Antihistamines
-Cough syrups
-Cold and flu medications
Useful For
Biochemical diagnosis and monitoring of intestinal carcinoid syndrome
Reference Range Information
Performing Location Reference Range
​Mayo Medical Laboratories ​<=8 mg/24 hours
Interpretation
Elevated excretion of 5-hydroxyindoleacetic acid is a probable indicator of the presence of a serotonin-producing tumor, if pharmacological and dietary artifacts have been ruled out.
For more information visit:
Performing Laboratory Information
Performing Location Day(s) Test Performed Analytical Time Methodology/Instrumentation
​Mayo Medical Laboratories ​Monday through Thursday; 11 a.m.;
Friday: 2 p.m.		 ​2 days (not reported on Saturdays or Sundays) ​Solid Phase Extraction (SPE) and Liquid Chromatography/Tandem Mass Spectrometry (LC/MS/MS) analysis
Reference Lab
Mayo Clinic Laboratories
For billing questions, see Contacts
Outreach CPTs
CPT Modifier
(if needed)		 Quantity Description Comments
​83497 ​ ​1 ​ ​
Classification
This test was developed and its performance characteristics determined by Mayo Medical Laboratories.
For most current information refer to the Marshfield Laboratory online reference manual.