5-Hydroxyindoleacetic Acid (5-HIAA), 24-Hour Urine
- $184.95
The following is a list of what is included in the item above. Click the test(s) below to view what biomarkers are measured along with an explanation of what the biomarker is measuring.
5-HIAA, Urine
Creatinine, Urine
Total Volume
The 5-Hydroxyindoleacetic Acid (5-HIAA), 24-Hour Urine test contains 1 test with 3 biomarkers.
Brief Description: The 5-Hydroxyindoleacetic Acid (5-HIAA) 24-hour urine test is a diagnostic test that measures the amount of 5-HIAA in the urine collected over a 24-hour period. 5-HIAA is the primary metabolite of serotonin, a neurotransmitter found primarily in the brain, gastrointestinal tract, and platelets. By assessing the levels of 5-HIAA, health care providers can gain insight into the body's serotonin metabolism.
Collection Method: Urine Collection
Specimen Type: Urine
Test Preparation: No preparation required
When and Why a 5-Hydroxyindoleacetic Acid 24-Hour Urine Test May Be Ordered
A healthcare provider may order the 5-HIAA urine test under the following circumstances:
- Suspicion of Carcinoid Tumors: These are slow-growing tumors typically found in the gastrointestinal tract or lungs. These tumors often release large amounts of serotonin, leading to elevated 5-HIAA levels in the urine.
- Monitoring Treatment: In patients diagnosed with a carcinoid tumor and undergoing treatment, the test can help in monitoring the effectiveness of the treatment.
- Carcinoid Syndrome Symptoms: If a patient presents with symptoms such as flushing, diarrhea, abdominal pain, and difficulty breathing, which are characteristic of carcinoid syndrome.
What the 5-Hydroxyindoleacetic Acid 24-Hour Urine Test Checks For
This test specifically measures the amount of 5-HIAA excreted in the urine over a 24-hour period. Elevated levels of 5-HIAA can indicate an increased production and breakdown of serotonin, which is often associated with the presence of a carcinoid tumor.
Additional Lab Tests Ordered Alongside the 5-Hydroxyindoleacetic Acid 24-Hour Urine Test
When a 24-Hour Urine 5-HIAA test is ordered, it's typically part of a broader evaluation for carcinoid syndrome and neuroendocrine tumors. Here are some tests commonly ordered alongside it:
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- Purpose: To measure chromogranin A levels in the blood, a marker often elevated in patients with neuroendocrine tumors.
- Why Is It Ordered: CgA can help in the diagnosis and monitoring of neuroendocrine tumors, complementing the 5-HIAA test.
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- Purpose: To measure the level of serotonin in the blood.
- Why Is It Ordered: Since carcinoid tumors often secrete serotonin, elevated levels can support the diagnosis.
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- Purpose: To evaluate overall blood health, including red and white blood cells, and platelets.
- Why Is It Ordered: To assess for anemia or other hematological abnormalities that can occur with chronic illness or as a result of the tumor.
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- Purpose: To assess the health of the liver (enzymes, bilirubin, protein levels).
- Why Is It Ordered: To evaluate for liver involvement or metastasis, which can occur with advanced neuroendocrine tumors.
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- Purpose: To measure the level of pancreatic polypeptide, which can be elevated in some patients with neuroendocrine tumors.
- Why Is It Ordered: To provide additional information on pancreatic function and to assist in the diagnosis of neuroendocrine tumors.
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Gastrin, Insulin, and Glucagon Levels:
- Purpose: To measure levels of various hormones that can be produced by neuroendocrine tumors.
- Why Is It Ordered: To assess for the presence of other types of functional neuroendocrine tumors.
These tests, when ordered alongside a 24-Hour Urine 5-HIAA test, provide a comprehensive evaluation for the diagnosis and management of carcinoid tumors and related neuroendocrine tumors. They help in confirming the diagnosis, determining the extent of the disease, and guiding treatment decisions. The specific combination of tests will depend on the individual's symptoms, clinical presentation, and suspected location of the tumor.
Conditions or Diseases Requiring a 5-Hydroxyindoleacetic Acid 24-Hour Urine Test
The primary condition that this test screens for is carcinoid tumors, especially those associated with carcinoid syndrome. Carcinoid syndrome is a set of symptoms that result from the release of large amounts of serotonin and other chemicals by carcinoid tumors.
Usage of 5-Hydroxyindoleacetic Acid 24-Hour Urine Test Results by Health Care Providers
Elevated levels of 5-HIAA in the urine are a strong indicator of a carcinoid tumor. However, certain foods and medications can also affect 5-HIAA levels, so it's essential to consider the patient's diet and medication history. If the test indicates elevated levels of 5-HIAA, the healthcare provider will likely order further tests, including imaging studies, to locate and assess the tumor's size and spread.
On the other hand, if a patient known to have a carcinoid tumor shows reduced 5-HIAA levels after treatment, it may indicate that the treatment is effective. Regular monitoring using the 5-HIAA test can help in tracking the disease's progression and the treatment's effectiveness.
Most Common Questions About the 5-Hydroxyindoleacetic Acid (5-HIAA), 24-Hour Urine test:
Understanding the Basics
What is the purpose of the 5-Hydroxyindoleacetic Acid 24-Hour Urine test?
The 5-Hydroxyindoleacetic Acid (5-HIAA) 24-Hour Urine test measures the amount of 5-HIAA, a metabolite of serotonin, in urine over a 24-hour period. The test is primarily used to detect and monitor carcinoid tumors, which are rare tumors that secrete large amounts of serotonin.
Why is the 5-HIAA level important?
The 5-HIAA level is essential because it reflects the amount of serotonin being metabolized and excreted by the body. Elevated levels of 5-HIAA may indicate the presence of a carcinoid tumor, as these tumors often produce excessive serotonin. Monitoring 5-HIAA levels can also help determine the effectiveness of treatments and check for tumor recurrence.
Medical Implications and Applications
How is the 5-Hydroxyindoleacetic Acid 24-Hour Urine test helpful in diagnosing carcinoid tumors?
Carcinoid tumors, originating from neuroendocrine cells, often produce an excess of several hormones, with serotonin being one of the most prominent. When serotonin is metabolized, 5-HIAA is produced and then excreted in the urine. By measuring 5-HIAA levels in the urine over a 24-hour period, healthcare providers can gain insights into the body's serotonin production, indirectly indicating the potential presence of a carcinoid tumor.
Can the 5-Hydroxyindoleacetic Acid 24-Hour Urine test be used to monitor the progress of carcinoid tumor treatment?
Yes, the 5-Hydroxyindoleacetic Acid 24-Hour Urine test can be utilized to monitor the progress of carcinoid tumor treatment. A decline in 5-HIAA levels after treatment initiation typically indicates a positive response to the treatment. On the other hand, rising levels might suggest tumor growth or recurrence. Regular monitoring helps tailor the treatment plan to the patient's needs.
General Knowledge and Considerations
Is the 5-Hydroxyindoleacetic Acid 24-Hour Urine test the only method to detect carcinoid tumors?
While the 5-Hydroxyindoleacetic Acid 24-Hour Urine test is a valuable diagnostic tool for carcinoid tumors, it's not the only method. Other tests, such as blood tests, imaging scans (like CT or MRI), and tissue biopsies, are also employed to diagnose and assess the extent of carcinoid tumors. The urine test is a non-invasive way to screen and monitor the disease, but a comprehensive diagnosis usually involves a combination of multiple tests.
What conditions or factors might falsely elevate 5-HIAA levels, making them appear higher than they truly are?
Certain foods, such as bananas, tomatoes, pineapples, plums, and walnuts, as well as beverages like coffee and tea, can elevate 5-HIAA levels in the urine. Additionally, specific medications, including acetaminophen, cough syrups, diazepam, MAO inhibitors, and methocarbamol, might also increase 5-HIAA levels. It's essential to discuss diet and medication with a healthcare provider before undergoing the test to ensure accurate results.
Test Interpretation
What do normal and abnormal results from the 5-Hydroxyindoleacetic Acid 24-Hour Urine test indicate?
Normal results indicate that the levels of 5-HIAA in the urine are within the typical range, suggesting that there's no excessive serotonin production. This result usually indicates the absence of a carcinoid tumor or effective management of a known tumor. Abnormal or elevated results suggest increased serotonin metabolism, which can be indicative of a carcinoid tumor. However, elevated levels can also result from specific foods, medications, or other conditions, so further testing and assessment are crucial for a definitive diagnosis.
We advise having your results reviewed by a licensed medical healthcare professional for proper interpretation of your results.