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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 (5-Hydroxyindolacetic Acid)
5-OH-Indoleacetic Acid
Carcinoid Syndrome
HIAA (Hydroxyindoleacetic Acid)
Serotonin Metabolite

5-Hydroxyindoleacetic Acid  24 Hr U (HIAA)

24 HIAASO

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 from 24-hour urine collection
 ​10 mL Urine Tube ​Plastic Urine Container ​5 mL ​1 mL ​1 mL
Note:  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.​​​​​​​​
​ ​ ​ ​ ​ ​
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.

1. Some medications could interfere with test results. The ordering provider should decide if any medications should be stopped and when they should be restarted. If clinically feasible, discontinue the following medications at least 48 hours prior to, as well as during, specimen collection:

-Acetaminophen (Tylenol or generic versions)

-Tryptophan containing supplements

2. For 48 hours prior to, as well as during, the urine collection, the patient should:

Limit the following to one serving per day:

-Fruits

-Vegetables

-Nuts

-Caffeinated beverages or foods​

Collection Processing 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.

Specimen Stability Information
Specimen Type Temperature Time
​Urine ​ ​Refrigerate (preferred) ​56 days
​Frozen ​365 days
Rejection Criteria
All specimens will be evaluated at Mayo Clinic Laboratories for test suitability. 
Interference

Intake of food with a high content of serotonin (avocados, dates, eggplant, all fruit [including bananas, cantaloupe, grapefruit, kiwi fruit, 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.

-Acetaminophen (Tylenol or generic versions)

-Tryptophan containing supplements

Patient should also avoid caffeinated beverages such as tea and coffee or caffeinated foods, such as dark chocolate, for 48 hours before and during specimen collection.

Performing Laboratory Information
Performing Location Day(s) Test Performed Report Available​Methodology
​Mayo Clinic Laboratories ​Monday through Friday ​2 to 4 days​Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)
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 Clinic Laboratories ​5HIAA, mg/24 hour

99th percentile cutoff

Age

Female

Male

< or =23 months

< or =2.7

< or =2.3

24-35 months

< or =3.0

< or =2.6

3 years

< or =3.2

< or =2.9

4 years

< or =3.4

< or =3.2

5 years

< or =3.6

< or =3.6

6 years

< or =3.8

< or =3.9

7 years

< or =4.0

< or =4.2

8 years

< or =4.2

< or =4.5

9 years

< or =4.5

< or =4.8

10 years

< or =4.7

< or =5.1

11 years

< or =4.9

< or =5.3

12 years

< or =5.2

< or =5.6

13 years

< or =5.4

< or =5.8

14 years

< or =5.6

< or =6.1

15 years

< or =5.7

< or =6.3

16 years

< or =5.9

< or =6.4

17 years

< or =6.0

< or =6.6

18 years

< or =6.0

< or =6.7

19 years

< or =6.1

< or =6.8

20 years

< or =6.1

< or =6.9

21 years

< or =6.2

< or =6.9

22 years

< or =6.2

< or =7.0

23 years

< or =6.2

< or =7.0

24 years

< or =6.3

< or =7.1

25 years

< or =6.3

< or =7.2

26 years

< or =6.3

< or =7.2

27 years

< or =6.4

< or =7.3

28 years

< or =6.4

< or =7.4

29 years

< or =6.5

< or =7.5

30 years

< or =6.6

< or =7.5

31 years

< or =6.6

< or =7.6

32 years

< or =6.7

< or =7.7

33 years

< or =6.8

< or =7.7

34 years

< or =6.8

< or =7.8

35 years

< or =6.9

< or =7.9

36 years

< or =6.9

< or =7.9

37 years

< or =7.0

< or =8.0

38 years

< or =7.0

< or =8.1

39 years

< or =7.0

< or =8.2

40 years

< or =7.1

< or =8.2

41 years

< or =7.1

< or =8.3

42 years

< or =7.2

< or =8.4

43 years

< or =7.3

< or =8.5

44 years

< or =7.4

< or =8.6

45 years

< or =7.4

< or =8.7

46 years

< or =7.5

< or =8.8

47 years

< or =7.6

< or =8.9

48 years

< or =7.6

< or =9.0

49 years

< or =7.7

< or =9.1

50 years

< or =7.7

< or =9.2

51 years

< or =7.8

< or =9.3

52 years

< or =7.8

< or =9.4

53 years

< or =7.9

< or =9.5

54 years

< or =8.0

< or =9.6

55 years

< or =8.1

< or =9.7

56 years

< or =8.1

< or =9.7

57 years

< or =8.2

< or =9.8

58 years

< or =8.3

< or =9.8

59 years

< or =8.3

< or =9.8

60 years

< or =8.3

< or =9.9

61 years

< or =8.3

< or =9.9

62 years

< or =8.4

< or =9.9

63 years

< or =8.4

< or =10.0

64 years

< or =8.4

< or =10.0

65 years

< or =8.4

< or =10.0

66 years

< or =8.5

< or =10.1

67 years

< or =8.5

< or =10.1

68 years

< or =8.5

< or =10.1

69 years

< or =8.5

< or =10.2

70 years

< or =8.5

< or =10.2

71 years

< or =8.6

< or =10.2

72 years

< or =8.6

< or =10.2

73 years

< or =8.5

< or =10.1

74 years

< or =8.5

< or =10.1

75 years

< or =8.6

< or =10.1

76 years

< or =8.6

< or =10.0

77 years

< or =8.6

< or =10.0

78 years

< or =8.6

< or =10.0

79 years

< or =8.6

< or =10.0

80 years

< or =8.7

< or =9.9

81 years

< or =8.7

< or =9.9

82 years

< or =8.7

< or =9.9

83 years

< or =8.7

< or =9.9

84 years

< or =8.7

< or =9.9

85 years

< or =8.6

< or =9.8

86 years

< or =8.5

< or =9.8

87 years

< or =8.4

< or =9.7

88 years

< or =8.3

< or =9.7

89 years

< or =8.1

< or =9.5

90 years

< or =7.9

< or =9.4

91 years

< or =7.6

< or =9.2

92 years

< or =7.4

< or =9.0

93 years

< or =7.1

< or =8.8

94 years

< or =7.0

< or =8.7

= 95 years

< or =6.9

< or =8.6

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 (5-Hydroxyindolacetic Acid)
5-OH-Indoleacetic Acid
Carcinoid Syndrome
HIAA (Hydroxyindoleacetic Acid)
Serotonin Metabolite

5-Hydroxyindoleacetic Acid  24 Hr U (HIAA)

24 HIAASO

Ordering Applications
Ordering Application Description
​COM 5-Hydroxyindoleacetic Acid  24 Hr U (HIAA)
​Cerner ​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 from 24-hour urine collection
 ​10 mL Urine Tube ​Plastic Urine Container ​5 mL ​1 mL ​1 mL
Note:  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.​​​​​​​​
​ ​ ​ ​ ​ ​
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.

1. Some medications could interfere with test results. The ordering provider should decide if any medications should be stopped and when they should be restarted. If clinically feasible, discontinue the following medications at least 48 hours prior to, as well as during, specimen collection:

-Acetaminophen (Tylenol or generic versions)

-Tryptophan containing supplements

2. For 48 hours prior to, as well as during, the urine collection, the patient should:

Limit the following to one serving per day:

-Fruits

-Vegetables

-Nuts

-Caffeinated beverages or foods​

Collection Processing 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.

Specimen Stability Information
Specimen Type Temperature Time
​Urine ​ ​Refrigerate (preferred) ​56 days
​Frozen ​365 days
Rejection Criteria
All specimens will be evaluated at Mayo Clinic Laboratories for test suitability. 
Interference

Intake of food with a high content of serotonin (avocados, dates, eggplant, all fruit [including bananas, cantaloupe, grapefruit, kiwi fruit, 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.

-Acetaminophen (Tylenol or generic versions)

-Tryptophan containing supplements

Patient should also avoid caffeinated beverages such as tea and coffee or caffeinated foods, such as dark chocolate, for 48 hours before and during specimen collection.

Useful For
Biochemical diagnosis and monitoring of intestinal carcinoid syndrome
Reference Range Information
Performing Location Reference Range
​Mayo Clinic Laboratories ​5HIAA, mg/24 hour

99th percentile cutoff

Age

Female

Male

< or =23 months

< or =2.7

< or =2.3

24-35 months

< or =3.0

< or =2.6

3 years

< or =3.2

< or =2.9

4 years

< or =3.4

< or =3.2

5 years

< or =3.6

< or =3.6

6 years

< or =3.8

< or =3.9

7 years

< or =4.0

< or =4.2

8 years

< or =4.2

< or =4.5

9 years

< or =4.5

< or =4.8

10 years

< or =4.7

< or =5.1

11 years

< or =4.9

< or =5.3

12 years

< or =5.2

< or =5.6

13 years

< or =5.4

< or =5.8

14 years

< or =5.6

< or =6.1

15 years

< or =5.7

< or =6.3

16 years

< or =5.9

< or =6.4

17 years

< or =6.0

< or =6.6

18 years

< or =6.0

< or =6.7

19 years

< or =6.1

< or =6.8

20 years

< or =6.1

< or =6.9

21 years

< or =6.2

< or =6.9

22 years

< or =6.2

< or =7.0

23 years

< or =6.2

< or =7.0

24 years

< or =6.3

< or =7.1

25 years

< or =6.3

< or =7.2

26 years

< or =6.3

< or =7.2

27 years

< or =6.4

< or =7.3

28 years

< or =6.4

< or =7.4

29 years

< or =6.5

< or =7.5

30 years

< or =6.6

< or =7.5

31 years

< or =6.6

< or =7.6

32 years

< or =6.7

< or =7.7

33 years

< or =6.8

< or =7.7

34 years

< or =6.8

< or =7.8

35 years

< or =6.9

< or =7.9

36 years

< or =6.9

< or =7.9

37 years

< or =7.0

< or =8.0

38 years

< or =7.0

< or =8.1

39 years

< or =7.0

< or =8.2

40 years

< or =7.1

< or =8.2

41 years

< or =7.1

< or =8.3

42 years

< or =7.2

< or =8.4

43 years

< or =7.3

< or =8.5

44 years

< or =7.4

< or =8.6

45 years

< or =7.4

< or =8.7

46 years

< or =7.5

< or =8.8

47 years

< or =7.6

< or =8.9

48 years

< or =7.6

< or =9.0

49 years

< or =7.7

< or =9.1

50 years

< or =7.7

< or =9.2

51 years

< or =7.8

< or =9.3

52 years

< or =7.8

< or =9.4

53 years

< or =7.9

< or =9.5

54 years

< or =8.0

< or =9.6

55 years

< or =8.1

< or =9.7

56 years

< or =8.1

< or =9.7

57 years

< or =8.2

< or =9.8

58 years

< or =8.3

< or =9.8

59 years

< or =8.3

< or =9.8

60 years

< or =8.3

< or =9.9

61 years

< or =8.3

< or =9.9

62 years

< or =8.4

< or =9.9

63 years

< or =8.4

< or =10.0

64 years

< or =8.4

< or =10.0

65 years

< or =8.4

< or =10.0

66 years

< or =8.5

< or =10.1

67 years

< or =8.5

< or =10.1

68 years

< or =8.5

< or =10.1

69 years

< or =8.5

< or =10.2

70 years

< or =8.5

< or =10.2

71 years

< or =8.6

< or =10.2

72 years

< or =8.6

< or =10.2

73 years

< or =8.5

< or =10.1

74 years

< or =8.5

< or =10.1

75 years

< or =8.6

< or =10.1

76 years

< or =8.6

< or =10.0

77 years

< or =8.6

< or =10.0

78 years

< or =8.6

< or =10.0

79 years

< or =8.6

< or =10.0

80 years

< or =8.7

< or =9.9

81 years

< or =8.7

< or =9.9

82 years

< or =8.7

< or =9.9

83 years

< or =8.7

< or =9.9

84 years

< or =8.7

< or =9.9

85 years

< or =8.6

< or =9.8

86 years

< or =8.5

< or =9.8

87 years

< or =8.4

< or =9.7

88 years

< or =8.3

< or =9.7

89 years

< or =8.1

< or =9.5

90 years

< or =7.9

< or =9.4

91 years

< or =7.6

< or =9.2

92 years

< or =7.4

< or =9.0

93 years

< or =7.1

< or =8.8

94 years

< or =7.0

< or =8.7

= 95 years

< or =6.9

< or =8.6

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 Report Available​Methodology
​Mayo Clinic Laboratories ​Monday through Friday ​2 to 4 days​Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)
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.