5'-hydroxyindole acetic acid (5HIAA), urine
Clinical Background:
Intestinal carcinoid tumours along with neuroendocrine tumours can produce excess amounts of serotonin (5-hydroxytryptamine, 5-HT), which is a vasoactive, powerful smooth muscle stimulant. Serotoni...
Intestinal carcinoid tumours along with neuroendocrine tumours can produce excess amounts of serotonin (5-hydroxytryptamine, 5-HT), which is a vasoactive, powerful smooth muscle stimulant. Serotonin is metabolised to 5-hydroxyindoleacetic acid (5-HIAA) and excreted into urine. Elevated 5-HIAA levels are almost always associated with carcinoid syndrome while mildly elevated levels can occur in non-tropical sprue or from a dietary source such as walnuts, bananas and other serotonin containing fruits.
Test Details
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Discipline:
Biochemistry
Biochemistry
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Specimen Container Adult:
24 urine collection: a 24 hour urine collected into a container with sand and sulphuric acid preservative.
Overnight urine collection: an overnight urine collection into a container with sand and s...
Read More24 urine collection: a 24 hour urine collected into a container with sand and sulphuric acid preservative.
Overnight urine collection: an overnight urine collection into a container with sand and sulphuric acid preservative.
Random urine collection: white universal container [Send to laboratory immediately].
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Specimen Container Paediatric:
Random urine collection: white universal container [Send to laboratory immediately].
Random urine collection: white universal container [Send to laboratory immediately].
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Minimum Volume Adult:
1 - 10 mL urine
1 - 10 mL urine
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Minimum Volume Paediatric:
1 - 10 mL urine
1 - 10 mL urine
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Special Requirement:
Screening: Overnight urine with sand/sulphuric acid preservative. Random urine acceptable if sent to lab immediately.
Diagnosis and monitoring of known carcinoid: 24h urine with sand/sulphuric acid...Read MoreScreening: Overnight urine with sand/sulphuric acid preservative. Random urine acceptable if sent to lab immediately.
Diagnosis and monitoring of known carcinoid: 24h urine with sand/sulphuric acid preservative. -
Sample Stability:
Once pH has been adjusted to 3.0-3.5, samples are stable at 4°C for up to 10 days.
For long-term storage, store samples at –20°C.
Once pH has been adjusted to 3.0-3.5, samples are stable at 4°C for up to 10 days.
For long-term storage, store samples at –20°C.
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Transport Requirements:
Ambient temperature.
Ambient temperature.
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Interpretation:
Elevated excretion of urine 5-hydroxyindoleacetic acid (5-HIAA) is a probable indicator of the presence of a serotonin-producing tumor, if pharmacological and dietary artifacts have been ruled out....
Read MoreElevated excretion of urine 5-hydroxyindoleacetic acid (5-HIAA) is a probable indicator of the presence of a serotonin-producing tumor, if pharmacological and dietary artifacts have been ruled out.
Intake of food with a high content of serotonin (avocados, bananas, plums, walnuts, pineapple, aubergine, tomatoes/tomato products, kiwifruit, dates, grapefruit, nuts, cantaloupe/honeydew melon) within 48 hours of the urine collection could result in falsely elevated 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. -
Reference Ranges:
24-hour urine collection:
Less than 40 µmol/24h
Random (and overnight) urine collection:
Less than 4.0 µmol/mmol creatinine24-hour urine collection:
Less than 40 µmol/24h
Random (and overnight) urine collection:
Less than 4.0 µmol/mmol creatinine -
Factors Affecting Result:
Intake of food with a high content of serotonin (avocados, bananas, plums, walnuts, pineapple, aubergine, tomatoes/tomato products, kiwifruit, dates, grapefruit, nuts, cantaloupe/honeydew melon) wi...
Read MoreIntake of food with a high content of serotonin (avocados, bananas, plums, walnuts, pineapple, aubergine, tomatoes/tomato products, kiwifruit, dates, grapefruit, nuts, cantaloupe/honeydew melon) within 48 hours of the urine collection could result in falsely elevated 5-HIAA excretion.
Drugs that can increase 5-HIAA secretion include paracetamol, caffeine, diazepam (Valium), nicotine, some cough medicines (containing ephedrine or glyceryl guaiacolate, and phenobarbital. Drugs hat can decrease 5-HIAA include aspirin, ethyl alcohol, imipramine, levodopa, MAO inhibitors, heparin, isoniazid, methyldopa, and tricyclic antidepressants. If possible, following discussion with a doctor, potential interfering drugs should be discontiued at least 48-hours prior to and during urine collection.
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Routine Contact Name:
Duty biochemist
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Routine Telephone:
Freeman: 0191 244 8889
RVI: 0191 282 9719Freeman: 0191 244 8889
RVI: 0191 282 9719 -
Routine Email:
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Specialist Test:
Yes
Yes