24 hour urine collection (random/spot urine sample is not suitable)
Food high in serotonin content (avocados, bananas, tomatoes, plums, walnuts, pineapples and eggplant) should be avoided for 3 to 4 days prior to and during the urine collection, otherwise falsely elevated 5-HIAA results may be obtained.
Age and sex appropriate reference ranges and units are reported with all clinical results. Reference ranges and units can also be found on the ‘Procedure Catalogue’ in EPIC.
Measurement of urinary 5-HIAA is useful in the diagnosis and monitoring of patients with the carcinoid syndrome. Excessive serotonin secretion is responsible for many of the symptoms associated with carcinoid syndrome, including: flushing, diarrhoea, bronchoconstriction, wheezing, right heart valve disease, and fibrosis of the endocardium, blood vessels, and skin.
Carcinoid tumours are small, slowly growing tumours of enterochromaffin cells, which are part of the neuroendocrine system. Generally, carcinoid tumours are indolent, but a subset is malignant. Serotonin is primarily metabolized to 5-HIAA in the liver and kidney. 5-HIAA is water soluble and excreted almost entirely in the urine.
https://labtestsonline.org.uk/
This test is referred to an external laboratory for analysis.
2 – 4 weeks
This test can be added onto 24 hour urine samples up to 4 days from sample receipt.
Please refer to the UKAS website for test accreditation status.
Search UKAS accredited organisations
1. On waking, empty your bladder/discard your first morning void. Note the time when this occurs. This is the “starting time”. Write this time and the date in the space provided on the label of the urine container.
2. Collect all of the urine passed throughout the rest of the day and night, until the same start time the following morning. Your first void of the morning should also be collected and added to the urine container, so that a full 24 hour urine has been collected. Write this time and the date in the space provided on the label of the urine container.
3. Remember to collect any urine before opening your bowels, or you may forget and lose some of the collection in the toilet.
4. If you make a mistake, throw away all of the urine collected and start again on the following morning.
24 hour urine collection instructions for patients
Specimen Labelling Procedure
8210
