5- HIAA

The 5-HIAA test is a urine analysis used to measure the levels of 5-hydroxyindoleacetic acid (5-HIAA), a product of serotonin metabolism in the liver. Serotonin is a hormone that plays a key role in nerve impulse transmission, affecting sleep and mood, and is normally excreted through urine. This type of biochemical urine analysis is part of the services offered by the private laboratory in Belgrade, IntroLab.

Why is the 5-HIAA test done?

This analysis is most commonly performed if there is suspicion of a carcinoid tumor. These tumors secrete serotonin, leading to increased production of 5-HIAA. Symptoms of a carcinoid tumor can vary, but typically include:

• Facial and neck flushing
• Diarrhea and abdominal cramps
• Nausea and vomiting
• Low blood pressure
• Unexplained weight loss
• Irregular heart activity
• Watery eyes
• Asthma-like symptoms
• Sexual dysfunction in men

How is the analysis performed?

This analysis requires a 24-hour urine sample. It is important to keep the sample in a cool, dark place during collection.

Interpreting the results

Normal results range from 2 to 9 milligrams (mg) of 5-HIAA over 24 hours. Women usually have lower levels than men. Elevated levels of 5-HIAA may indicate carcinoid tumors, non-carcinoid tumors, cystic fibrosis, or malabsorption. Decreased levels of 5-HIAA may indicate depression or migraines.

Preparation for the test

It is recommended to avoid foods containing serotonin at least 3 days before the test or during the testing period. Also, you may need to stop taking certain medications before the test. Be sure to inform your doctor about all medications, vitamins, and supplements you are taking. This includes over-the-counter medications and any illegal drugs you may be consuming.

Possible factors affecting the results

Consumption of certain foods containing serotonin can increase 5-HIAA levels. These foods include bananas, pineapple, kiwi, plums, tomatoes, eggplant, avocado, and certain types of nuts, such as walnuts and pecans. Also, certain medications can increase or decrease 5-HIAA levels. These medications include acetaminophen, ethyl alcohol, some antidepressants, cough medicines or antihistamines, muscle relaxants. Strenuous physical activity can also raise 5-HIAA levels.

Test safety

This test is completely safe and carries no health risks for patients.

Cost and time required to obtain 5-HIAA test results

To perform the 5-HIAA test at IntroLab laboratory in Belgrade, it costs 1,420.00 RSD. Results are usually available within 4 days.