Catecholamines, Urine 24-hr Test
20,500 Kshs | Home Collection Available
Synonyms
dopamine, epinephrine, fractionation, urinary free catecholamines, norepinephrine.
Purpose
The Catecholamines, Urine 24-hr Test measures the levels of catecholamines, including epinephrine (adrenaline), norepinephrine (noradrenaline), and dopamine, excreted in the urine over 24 hours. Catecholamines are hormones produced by the adrenal glands and are released in response to stress or physical activity.
The test helps to:
- Diagnose and monitor tumors of the adrenal glands, such as pheochromocytoma and neuroblastoma
- Investigate symptoms like high blood pressure, headaches, rapid heart rate, sweating, and palpitations that suggest excess catecholamine production
- Evaluate the causes of secondary hypertension in patients who do not respond to standard treatments
- Monitor the effectiveness of treatment or detect recurrence after tumor removal
- Collecting urine over 24 hours provides a more accurate measurement of hormone levels than a single blood test, as catecholamines are released in short bursts and can fluctuate throughout the day.
To support diagnosis and improve clinical accuracy, the test can be done alongside Plasma Free Metanephrines, 24-Hour Urine Metanephrines, Imaging Studies, Blood Pressure Monitoring, Electrolyte Panel and Kidney Function Tests, and Chromogranin A Test.
This test plays a key role in identifying rare but serious conditions, guiding timely treatment, and preventing complications from hormone-secreting tumors.
Patient Preparation
The patient should avoid stress and drugs that may interfere with the test discontinue two weeks before the test.
Samples
30ml aliquot with a minimum volume of 4ml of urine, 24-hour collection in a brown urine container with 30ml 6N HCL preservative. All urine should be collected, including the final specimen at the end of the 24-hour collection period, mixed, and the lid secured. Label the container with the patient’s details (name, date of collection, time). Add preservative to the container before collection. The sample should be refrigerated during and after collection.
Reference Range
Epinephrine: 0-20µg/24hrs, norepinephrine;0-135µg/24hrs, dopamine:0-150µg/24hrs
Results Turnaround
4-7days after receipt of samples.
Diseases / Diagnostic indicators
The 24-hour Urine Catecholamines Test is primarily used to help diagnose rare tumors that produce excess catecholamines, such as:
- Pheochromocytoma – a tumor of the adrenal medulla that causes high levels of epinephrine and norepinephrine, leading to episodes of high blood pressure, headaches, sweating, and palpitations
- Neuroblastoma – a cancer that develops from immature nerve cells, typically affecting infants and young children, and can produce elevated catecholamines
- Paraganglioma – a related tumor occurring outside the adrenal glands, also capable of catecholamine overproduction
These conditions may cause symptoms that come and go, making hormone testing over 24 hours more reliable.
Some possible outcomes of the test include:
Elevated Catecholamine Levels:
Suggest overproduction by tumors such as pheochromocytoma, paraganglioma, or neuroblastoma. Further imaging and confirmatory tests are usually needed to locate and characterize the tumor.
Normal Catecholamine Levels:
Indicate that the symptoms are unlikely due to excess catecholamines. However, if symptoms persist, doctors may explore other causes or repeat the test if a tumor is still suspected.
Mildly Elevated Levels:
It can result from stress, medications (e.g., decongestants, antidepressants), or certain foods. A detailed review of medications and possible repeat testing may be needed.
This test provides critical diagnostic information, allowing early detection and treatment of hormone-secreting tumors, which can be life-threatening if left unmanaged.
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