5-HIAA
- Description
- Analysis by liquid chromatography-tandem mass spectrometry (LC-MS/MS)
- Clinical details
5-Hydroxy-indole-acetic acid (5-HIAA) is the metabolite of 5-hydroxytryptamine (serotonin). Serotonin is produced by the argentaffin cells of the GI tract. Serotonin is over-produced in the carcinoid tumours of the GI tract. These are associated with flushing attacks, diarrhoea and abdominal pain. Most carcinoid tumours are metastatic to the liver at the time of detection. Resection of the primary tumour, partial hepatectomy and embolization are the primary forms of treatment, although radiolabelled octreotide has been used more recently. 5-HIAA is invariably increased in classical carcinoid, although some tumours may be non-secretory. 5-HIAA is also increased with high dietary serotonin intake or other GI tract disease e.g. coeliac disease.
- Reference range
< 42 umol/24h or <4.0 umol/mmol creat
- Units
umol/24h (timed) or umol/mmol creat (random)
- Testing site
- Synnovis : Reference Services : Blackfriars Hub
- Laboratory
- Metabolic
- Sample type and volume required
Timed (24h) urine collections are preferred for investigations of adults for carcinoid syndrome. Samples should be collected into containers with an anti-bacterial agent (boric acid) or into acid containing bottles. Acidification of the sample prior to despatch provides greater stability for the analytes measured. A 10-25 mL aliquot is preferred with the 24h urine volume provided. Random samples can be used in adults. Please see below for 24hr Urine Collection instructions:
- Storage and transport
Send by overnight first class post.
- Turnaround time
7 working days
- Patient instructions
Pre-sample preparation is important for accurate 5HIAA test results. Food staff rich in serotonin should be avoided for 48hr prior to and during urine collection. These include avocados, bananas, pineapples, plums, walnuts, tomatoes, kiwi fruit, sweetcorn, broccoli, spinach and eggplant. There are also certain cough medicine that contain serotonin that can affect the 5HIAA test
- Contacts
Metabolic Laboratory at Blackfriars Hub
Phone: 020 4591 0011
Email: Metabolic.Laboratory@synnovis.co.uk
Metabolic Laboratory at Synnovis
Reference Chemistry, Floor One
Friars Bridge Court, 41-43 Blackfriars Road
London, SE1 8NZ