Catecholamine Blood Test
Catecholamines is a general term for several hormones that naturally occur in your body, mainly dopamine, norepinephrine, and epinephrine. Your body produces more catecholamines during times of stress. They make your heart beat faster, your blood pressure rise, and in general prepare your body to respond to stress.
What Does the Catecholamine Blood Test Do?
The catecholamine blood test determines whether the level of catecholamines in your blood is too high.
Why Has My Doctor Ordered a Catecholamine Blood Test?
Most likely, your doctor has ordered a catecholamine blood test because he or she is concerned that you might have a pheochromocytoma. This is a tumor that grows on your adrenal gland, where catecholamines are released. Most pheochromocytomas are benign, but it is important to have them removed so they do not interfere with regular adrenal function.
Your Child and the Catecholamine Blood Test
Your child’s doctor may order a catecholamine blood test for your child if he or she is concerned your child has neuroblastoma, a common childhood cancer. According to the National Cancer Institute (NCI), two-thirds of cancers in children below the age of five are neuroblastomas. (NCI). The sooner a child is diagnosed with neuroblastoma and begins treatment, the better his or her chances of beating the disease. According to the Ped-Onc Resource Center, 90 percent of children under the age of 1 who are diagnosed with neuroblastoma will survive (Ped-Onc, 2011).
What Symptoms Would Make My Doctor Order a Catecholamine Blood Test?
The symptoms of a pheochromocytoma are:
- high blood pressure (although not everyone with high blood pressure has a pheochromocytoma)
- rapid heartbeat
- unusually hard heartbeat
- heavy sweating
- weight loss
- severe headaches off and on for an extended period
- pale skin
- unexplained weight loss
You might also feel unusually frightened for no reason, or feel strong, unexplained anxiety.
The symptoms of neuroblastoma are:
- painless lumps of tissue under the skin
- abdominal pain
- chest pain
- back pain
- bone pain
- swelling in the legs
- high blood pressure
- rapid heartbeat
- bulging eyeballs
- dark areas around the eyes
- any changes to the shape or size of eyes, including changes to the size of pupils
- unexplained weight loss
What Are the Possible Outcomes?
Because catecholamines are related to stress—even small amounts of stress—the level of catecholamines in your body changes based on whether you’re standing, sitting, or lying down (supine).
The Mayo Clinic Medical Laboratories list the normal, adult levels of catecholamines as:
- Norepinephrine: supine: 70 to 750 pg/mL; standing: 200 to 1,700 pg/mL
- Epinephrine: supine: undetectable to 110 pg/mL; standing: undetectable to 140 pg/mL
- Dopamine: less than 30 pg/mL (no postural change) (Mayo Clinic)
Children’s levels of catecholamines vary dramatically and change, in some cases, by the month, because of their rapid growth. Your child’s doctor will know what the healthy level is for your child.
High levels of catecholamines in adults or children can indicate the presence of neuroblastoma or a pheochromocytoma. Further testing will be needed.
How Do I Prepare for a Catecholamine Blood Test?
Your doctor may tell you not to eat or drink anything for six to 12 hours before the test. Follow your doctor’s orders carefully. Your test results could be incorrect if you don’t.
What Might Interfere With Readable Test Results?
There are a number of common medications, foods, and beverages that can interfere with catecholamine blood test results. Coffee, tea, and chocolate are examples of things you might have recently consumed that make your catecholamine levels rise. Over-the-counter medications like allergy medicine could also interfere with the reading. Your doctor should give you a list of things to avoid before your test. Make sure to tell your doctor all the medicines you are taking, both prescription and over-the-counter.
Since catecholamine levels in blood are affected by even small amounts of stress, some people’s levels may rise because they are nervous about having a blood test.
Breastfeeding mothers also need to check with their doctor about their intake before their child’s catecholamine blood test, since catecholamines pass from mother to child through breast milk.
What Happens in the Test?
A small sample of blood is taken from your veins. You will probably be asked to remain quietly seated or to lie down for as long as half an hour before your test.
The person assisting your doctor will tie a tourniquet around your upper arm and look for a vein large enough to insert a small needle in. When they’ve located the vein, they will clean the area around it to make sure no germs are introduced into your bloodstream. Next, they will insert a needle connected to a small vial into which some of your blood will collect. This could sting a little. The collected blood is sent to a diagnostic lab for accurate reading.
Sometimes, the person taking your blood sample will access one of the veins on the back of your hand instead of inside your elbow.
What Are the Next Steps?
Your test results should be ready in a couple of days. Your doctor will read them and discuss likely next steps.
The catecholamine blood test is not a definitive test for a pheochromocytoma, neuroblastoma, or any other condition, but it does help your doctor narrow down the list of ailments that could be causing your symptoms. More testing will need to be done, including possibly a catecholamine urine test.