Contents
Catecholamines are hormones produced by the adrenal glands. They are released when a person experiences physical or emotional stress. These hormones include epinephrine, norepinephrine and dopamine and also play important roles in the human body. They send nerve impulses to the brain, narrow blood vessels, and increase the heart rate.
People who have a rare type of tumor called a pheochromocytoma have high levels of catecholamines in their urine. They cause high blood pressure. Approximately 95% of these tumors are found in the abdominal cavity.
The patient may need this test if the doctor suspects a tumor, a pheochromocytoma. Signs and symptoms may include: headaches; excessive sweating; rapid pulse; labored breathing; panic attacks; high blood pressure.
It is worth noting that not all patients with this type of tumor have high blood pressure. Up to 15% of patients with pheochromocytoma have normal values.
Other symptoms include heart palpitations, weakness, and panic attacks. Less common symptoms include blurry vision and weight loss.
The doctor may also order additional tests and tests, including: a blood test; computed tomography (CT) or magnetic resonance imaging (MRI) scans; iodine-123-metaiodobenzylguanidine scintigraphy.
Test results may vary depending on age, gender, medical history, method used for the test, etc.
The following amount can be considered the norm: norepinephrine – less than 170 mcg / 24 hours; adrenaline – less than 35 mcg / 24 hours; dopamine – less than 700 mcg / 24 hours; normetanephrine – less than 900 mcg / 24 hours; metanephrine – less than 400 mcg / 24 hours. Higher levels of these hormones may mean that the patient has a pheochromocytoma tumor.
Algorithm for conducting a urine test for catecholamines
This test requires a 24-hour urine sample. For this sample, the patient must collect all of their urine within 24 hours. It is necessary to empty the bladder completely in the morning, without collecting urine. It is important to pay attention to the time and then collect the urine each time the need arises for the next 24 hours. Keep the container with the collected urine in a tightly closed state in the refrigerator. The analysis is submitted to the laboratory in the morning of the next day. The results of the analyzes are transferred to the doctor who wrote out this referral, or the patient himself can pick them up at the appointed time. Usually the results are known the next day.
Urinalysis for catecholamines poses no known risks.
What can affect the results of a urinalysis for catecholamines?
Some medicines may affect the results. These include tricyclic antidepressants and allergy medications. Food products can also affect the results of the analysis, including:
- coffee, including decaffeinated coffee;
- tea;
- chocolate;
- vanilla, including foods and drinks containing vanilla;
- bananas;
- oranges and other citrus fruits;
- walnuts;
- avocado;
- beans;
- cheese;
- beer and red wine;
- licorice;
- products containing wheat flour.
Preparing to test urine for catecholamines
Before taking a urine test for catecholamines, it is recommended that you stop taking tricyclic antidepressants at least 2 weeks before the start of the test. It is important to tell your doctor if you have any drug treatment and he may recommend lowering your dosage or stopping incompatible drugs.
The products listed in the above section should be avoided both before and during analysis. Before the test, the patient should not get into stressful situations, vigorous exercise and beware of viral and infectious diseases. It is important to stop smoking six hours before the test and throughout the day. If a woman has a period on the day of the test, you must inform your doctor about this.
Since the results of the analysis can be influenced by various factors, and tumors of the chromaffin type are rare, the results may be falsely positive. In order to confidently establish the diagnosis, it is necessary to conduct an additional and more thorough examination. During the period of establishing factors that could affect the results of the analysis, it is prescribed again in order to thoroughly verify whether the indicators of catecholamines in the urine have changed or not. In addition to a urine test for catecholamines, the doctor prescribes a test for metanephrine in the urine or blood, as well as an MRI of the abdominal cavity. If a tumor has already been diagnosed and treated, a newly elevated level of catecholamines may indicate tumor recurrence or treatment failure.
It is worth noting that a high level of the hormone in the patient’s urine may indicate the presence of tumors: ganglioneuroma; neuroblastomas; pheochromocytoma, etc.; about the presence of various forms of stress; about the development of myocardial infarction; about taking nicotine, adrenaline, ethyl alcohol, caffeine; about manic-depressive disorders; about reduced thyroid function. In turn, low levels of catecholamines may indicate the presence of neuropathies, diabetes mellitus or parkinsonism.
important points
Testing for catecholamines can help diagnose chromaffin tumors, but this test does not indicate the location of the tumor, its type (malignant or benign), or their number.
The amount of catecholamines in the urine does not always correspond to the size of the tumor, although there is a possibility of an increase in the amount of hormones with the growth of the tumor.
It is important that if the patient observes some negative changes in his body, it is recommended not to delay going to the doctor, as timely diagnosis and properly selected treatment will help get rid of a dangerous disease.