Top
30
Doctor insights on: Can You Explain The Relationship Between Catecholamines And Metanephrines

Share
1

1
Can you explain the relationship between catecholamines and metanephrines?

Can you explain the relationship between catecholamines and metanephrines?

Phenol vs ether: The chemical structure of epinephrine, the natural hormone generated in excess by a pheochromocytoma tumor, has an aromatic carbon ring with two adjacent -oh (phenol) groups and a side-chain amino group. Compounds with this structure are called catecholamines. Metanephrine is a metabolite of this hormone, with one phenol converted to an ether (-och3). If elevated, it implies the tumor. ...Read more

Dr. Creighton Wright
52 Doctors shared insights

Metanephrines (Definition)

Metanephrins are metabolic products of cathecolamines: epinephrin and norepinephrin and can be used to diagnose excess production of these adrenal/sympathetic hormones. They can be measured in blood and urine and are very elevated in a condition called pheochromocytoma which is a tumor found mostly in the adrenal glands ...Read more


4

4
Why do I have to refrain from tobacco for catecholamines  and metanephrine urine test?

Why do I have to refrain from tobacco for catecholamines  and metanephrine urine test?

Nicotine...: Tobacco contains nicotine. Nicotine gives the body its kick because it stimulates the adrenal glands to produce adrenaline. Adrenaline, or epinephrine, is a catecholamine. If you use tobacco, the test may return as a false positive. ...Read more

7

7
Should I redo 24 hrs urine test for catecholamines  metanephrine if I had a cigarette or just give it to lab?

Should I redo 24 hrs urine test for catecholamines  metanephrine if I had a cigarette or just give it to lab?

See below: Urine collection for metnephrines requires a lot of precautions. It would be better to redo. See the website given below for details about precautions or this test.
http://labtestsonline. Org/understanding/analytes/urine-metanephrine/tab/sample. ...Read more

8

8
Can you tell me about elevated catecholamines?

Can you tell me about elevated catecholamines?

Stress response: Hi. Elevated catecholamines are part of the "fight or flight" response mediated by the sympathetic nervous system in response to a serious threat to your survival. If someone has a tumor that makes catecholamines (pheochromocytoma or paraganglioma), they have elevated catecholamines, and usually bad high blood pressure, palpitations, sweating, headache, and pallor. Interesting stuff! ...Read more

9

9
What to do if everything you know about elevated catecholamines?

What to do if everything you know about elevated catecholamines?

Incomplete sentence: Hi. That's not a complete thought or question. Would you like to clarify it? I can tell you elevated catecholamines can be either physiological (the "fight or flight" response") or pathological (tumors of the adrenal medulla or related tissue). But I can't for the life of me understand what you're thinking or trying to ask. Good luck! ...Read more

10

10
What makes the plasma metanephrine test different?  

What makes the plasma metanephrine test different?  

Different from urine: The plasma test compared to the urine is newer and more sensitive.
In other words if you have pheochromocytoma the plasma test is less likely to miss the diagnosis by coming back normal. ...Read more

11

11
What does it mean if my metanephrines are low and 5-hiaa is high?

What does it mean if my metanephrines are low and 5-hiaa is high?

A test for carcinoid: The 5-hiaa level is a test for the carcinoid tumor. You need to discuss this issue with the doctor who ordered the test. Carcinoid is a slow growing neuroendocrine tumor that often originates in the appendix or other areas of the GI tract. ...Read more

12

12
Who would need a urine catecholamine fractionation?

Who would need a urine catecholamine fractionation?

Possible tumor: Urine catecholamines are separated into dopamine, epinephrine, norepinephrine, vma, and dopa, among others. Each of these metabolites are differently expressed by certain tumors, often in the adrenal gland, or sometimes in other sites. This gives a guide to where to test further, or what else may be giving rise to the symptoms (often high blood pressure, heart beat abnormalities, etc). ...Read more

13

13
Can methylphenidate causehigh lvls catecholamines fractionated blod test? +mking result undifferentiat so hyperadrnrgcpots cannot be diagnosis b/c of med use?

Can methylphenidate causehigh lvls catecholamines fractionated blod test? +mking result undifferentiat so hyperadrnrgcpots cannot be diagnosis b/c of med use?

Ritalin (methylphenidate) and POTS: Methylphenidate shows up as methampetamine in a blood test. To DX hyperadrenergic postural orthostatic tachycardia syndrome (pots) would be a clinical issue not primarily based on a blood test. I can see trying methylphenidate for the chronic fatigue aspects of pots, but the best treatment is often regular aerobic exercise. ...Read more

14

14
What is the definition or description of: 24hr urine catecholamines?

See below: A 24 hr urine catecholamine test is done to help diagnose and susequently resect a tumor in the adrenal glands called a pheochromocytoma which results in BP elevation to very high levels periodically.

It measures the amount of the hormones epinephrine, norepinephrine, metanephrine, and Dopamine in the urine. ...Read more

16

16
What does it mean when the metanephrine level is 23 on a 24 hour urinalysis?

What does it mean when the metanephrine level is 23 on a 24 hour urinalysis?

Normal: All laboratory results need to be interpreted in the clinical context and the doctor who ordered the tests is usually in the best position to do that. Having said that, your result seems to be normal. You may consult this site for more info on this topic.
https://medlineplus. Gov/ency/article/003613.htm ...Read more

17

17
Free metanephrine 64, total plasma metanephrine 301 and normetanephrine 237. 3 weeks post total thyroidectomy. Anything to worry about?

Laboratory normals: Your question cannot be answered unless we know the following:
1. What laboratory did the tests and what are their normal reference ranges.
2. Did you take any medications that could interfere with the assays?
3. Did you have any foods that might interfere with the assays?

Also, why were these tests done? If you are looking for a pheochromocytoma, they might help. Otherwise, probably not. ...Read more

19

19
What are the risks of catecholamine surges for fetus and mother?

What are the risks of catecholamine surges for fetus and mother?

Generally this is: In the context of some other problem.
Adrenal tumors with catecholemine surges just due to the chemicals. Raised blood pressure and risk of circulation cutting off (miscarriage). Drugs of abuse
http://www. Nerdpocalypse. Net/cocaine. Html and methamphetamine can be very dangerous with that.
Thru the main page, you can connect directly to me to ask more detailed questions http://www. Nerdpocalypse. Net ...Read more

20

20
Can you explain metanephrines?

Can you explain metanephrines?

BP related hormones: Metanephrines are hormone compounds related to the presence of an endocrine tumor called a pheochromacytoma. These tumors cause hypertension, the metanephrines are elevated in the blood and urine and mark the presence of the tumor. This test should lead to further localization of the tumor and possible removal. ...Read more

21

21
What is the definition or description of: metanephrines?

What is the definition or description of: metanephrines?

Metabolic product: Metanephrins are metabolic products of cathecolamines: epinephrin and norepinephrin and can be used to diagnose excess production of these adrenal/sympathetic hormones. They can be measured in blood and urine and are very elevated in a condition called pheochromocytoma which is a tumor found mostly in the adrenal glands that causes severe hypertension. ...Read more

22

22
What substances interfere with the plasma metanephrine test?  

What substances interfere with the plasma metanephrine test?  

Metanephrine: You should discontinue Epinephrine and epinephrine-like drugs for at least 1 week before the test, stop using Acetaminophen 48 hours beforehand, and fast for 8-10 hours prior to collection. It is especially important not to have any caffeine containing food (soda, chocolate), coffee (including decaf), tobacco (smoking cigarettes or cigars), tea, or alcohol for at least 4 hours before specimen coll. ...Read more

23

23
What causes low metanephrines in 24h urine?

What causes low metanephrines in 24h urine?

Low metanephrines: The answer to your question is too long to explain in the space provided. For the causes of low metanephrines go to this link and read about them : http://www. Webmd. Com/heart-disease/catecholamines-14697

Good luck. ...Read more

24

24
What is the reason for checking catecholamine levels in the urine?

What is the reason for checking catecholamine levels in the urine?

Pheo: Anyone found to have hypertension that isn't classic, or to have other symptoms of pheochromocytoma (or in a youngster, neuroblastoma) will get one or more catecholamine checks. ...Read more

26

26
What if the results are negative in the 24 hour catecholamine urine test?  

R/O adrenal tumor: Catecholamines are typically produced by functioing adrenal tumors causing elevated blood pressure and rapid pulse. This can be ruled out with a normal 24 hour test. ...Read more

27

27
What could a plasma metanephrines blood test mean if it is slightly elevated?

What could a plasma metanephrines blood test mean if it is slightly elevated?

Keep testing: Most labs are set up so that a few percent of healthies come out a bit high. You are getting worked up for pheochromocytoma, I bet. You will get seem real biochemical tests, and if others are suggestive, imaging. ...Read more

28

28
Should the urine tests still be performed even though the plasma free metanephrine has been done?  

Should the urine tests still be performed even though the plasma free metanephrine has been done?  

Often no: The plasma has more sensitive and more specific and generally adequate (better) in most situations. It would depend if the doctor is more worried about a false positive (finding pheochromcystoma you really don't have), or more worried about false negative (missing the disease when you really have it). Your doctor would decide based on your symptoms which is the bigger worry /risk. ...Read more

29

29
24 hour urine catecholamine for a pheo- if a person does not have an episode during the 24 hours would it still show elevated levels. If so how?

24 hour urine catecholamine for a pheo- if a person does not have an episode during the 24 hours would it still show elevated levels. If so how?

Usually, yes: A pheo usually secretes catecholamines continuously, so it is not usually necessary to time the collection. These catecholamines yield a lot of breakdown products (eg. metanephrines). However, in some circumstances, if there is a very high suspicion for pheo and the initial tests are negative, and the attacks are sporadic, a urine collection timed with the episode is reasonable. ...Read more

30

30
If mteanephrine, fractionated 24hrurine came back abnormal, what is the likehood that the metanephrine, fractionated blood test will be abnormal to?

If mteanephrine, fractionated 24hrurine came back abnormal, what is the likehood that the metanephrine, fractionated blood test will be abnormal to?

High: All laboratory results need to be interpreted in the clinical context and the doctor who ordered the tests is usually in the best position to do that. Having said that, For the diagnosis of pheochromocytoma, 24-hour urine test is better than plasma metanephrine levels. You may consult this site for information: https://www. Urmc. Rochester. Edu/encyclopedia/content. Aspx? Contenttypeid=167&contentid=metanephrines_blood ...Read more