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Maxx B
04-13-2014, 05:41 AM
To cut a long story short, I have a character that is ill. He has abnormally high levels of epinephrine and norepinephrine in his system. The doctor treating him does not know that hormones are not being produced by his own body, but rather from a plot device they will discover later. His other symptoms are anxiety, raised blood pressure, heart palpitations, paranoia and increasing levels of anger.

Blood and urine tests indicate high levels of the hormones, is Pheochromocytoma the only disease that a doctor would think to look for as a cause? If so what tests would they order. The doctor in question is an A&E / ER doctor.

ap123
04-13-2014, 06:21 AM
I'm not a doctor, but I think Cushing's would be one of the first, if not the first thing they look for.

Kregger
04-14-2014, 01:00 AM
An ER doc is going to test for illegal drugs based on pt's combined signs and symptoms. In a typical ER they look for the typical, anything outside of the ordinary usually gets turfed to medicine.

Maxx B
04-14-2014, 01:20 AM
An ER doc is going to test for illegal drugs based on pt's combined signs and symptoms. In a typical ER they look for the typical, anything outside of the ordinary usually gets turfed to medicine.

This is an ongoing case, the doctor is one of my MCs and for plot reasons is following up on the initial consult (the patient is my other MC). The epinephrine indicators have shown up in a 24 hour urine test. If she suspected Pheochromocytoma would she request MRI or different scans? I've read the wikipedia article on Pheochromocytoma, and am looking for information from someone in the medical field.

Maxx B
04-14-2014, 01:26 AM
I'm not a doctor, but I think Cushing's would be one of the first, if not the first thing they look for.

Cushing's is an excess of cortisol not epinephrine, also the patients symptoms does not match that of Cushing's. The illness only needs to present like Pheochromocytoma to act as a temporary distraction from the actual cause.

smellycat6464
04-14-2014, 01:00 PM
Hi there!

So I studied biochemistry--I don't have an MD (and MDs out there?) so I will give it my best shot!

Typically, epinephrine and norepinephrine are not released chronically. They are rather exhaustive on the body and aren't meant to hang around.

After googling that cancer you mentioned, the effects of norepinephrine would be more pronounced, as epinephrine biosynthesis would occur to a lesser (but greater than the physiological norm) extent.

But for the sake of your story, lets assume that your reader doesn't have a wikipedia's worth of knowledge on the pathology's fine details (heck, I didn't, and I did rather well in physiology).

Symptoms that might be worth including: Remember, if you're dealing with an overload of an acute stress response, the body is going undergo decreased appetite (but that may change after a period of increased basal metabolic rate), decreased immune function, and other tiny things. Whatever, isn't necessary to fighting or flighting is going to be disregarded.

The subject would most likely get the shakes, glycogen stores would be depleted (so he will use up readily available forms of energy rather fast), also, you got the high blood pressure down, but you also get restricted blood flow to the periphery (like your fingers), so tingling or numb hands might happen later. As for the palpitations, I can see that, but if this dude is getting pumped on these hormones, the rate will skyrocket and he could possibly get a heart attack.

However, other things can exacerbate the effects/half life of epinephrine. For example, if you want to know some of the nitty-gritty, epinephrine stimulates what's called a messenger cascade--it binds to a protein on a cell and "turns it on." This turned on protein generates a lot of signalers, typically one called "cyclic AMP" (or cAMP), which is similar to ATP. There are molecules we intake, typically stimulants like caffeine, that inhibit the breakdown of these cAMPS. With more cAMPs, the cell "does more stuff" (possibly synthesize more epinephrine, but I'm not sure.

As per diagnosing this condition, I think that p-word cancer is your best bet--I cant think of any others. But, the tests to confirm this wouldn't be urine based alone I'd imagine. They would start with urine, of course, and would probably consist of a catecholamine test: http://www.nlm.nih.gov/medlineplus/ency/article/003613.htm

^Here's some info on that diagnostic.

If the doctor suspected cancer, that would most likely lead to adrenal biopsies, which would of course turn up negative since the plot is causing these hormone levels to rise, not a tumorous growth.

I'd imagine the doctor would try to rule out other conditions, or conduct the biopsy as non invasively as possible--possibly through a laprascope (if I spelt that right).

Remember, the body's biochemical pathways are anything by isolated--affect one and you change them all. The body could ramp up cortisol production, too, since it is experiencing what it interprets as stress for long term. Cortisol is the long term stress hormone, not the "ephrines" as I call them (at least not to the same extent, oh, biology and your well of exceptional cases).

Well, that might have been too long-winded, but I hope it helped you out just a little. Remember, I'm no MD, so anyone is free to counter me on this. I'm just going off what I remembered in my biology classes.

Happy writing!

boron
04-15-2014, 12:29 AM
MaxxB, so discovering the high blood epinephrine level is the first event in this part of the story? Or the patient complains of symptoms first? I mean, from which exact reason a doctor start the tests? (The ongoing monitoring, as you mentioned?)

As for pheochromocytoma, other typical symptoms (not necessary always present) are: fever, excessive sweating, headache and excessive urination (excessive amount of urine, more than 3 liters per day).

Blood/urine epinephrine level is not a routine lab test. The first abnormal test in pheochromocytoma (or a device producing epinephrine...) would likely be increased blood (and urine) glucose levels. The next logical test would be glucose tolerance test (drinking a sugary liquid, then, after 2 hours, measuring glucose levels - this is to check for diabetes mellitus; pheochromocytoma actually causes temporary diabetes).

Other causes of increased epinephrine (with most symptoms you mentioned): severe stress, or overdose of caffeine, amphetamines or cocaine (urine tests can be done for the drugs).

The first imaging test in pheochromocytoma is CT. MRI is more expensive, so it is done as the first test in children or pregnant women to avoid excessive X-ray exposure.
Here's one easy-to-read article about pheochromocytoma (Mayo Clinic (http://www.mayoclinic.org/diseases-conditions/pheochromocytoma/basics/definition/con-20030435)). More detailed testing for pheochromocytoma (http://emedicine.medscape.com/article/124059-workup#showall). In your case, they would not find the tumor, so they would order scintigraphy, in which the contrast substance collects in the tumor. They would not find a tumor again, so they could think of other tumors.

In a rare multiple endocrine neoplasia, pheochromocytoma can appear together with a parathyroid and pituitary tumor, so the neck and head CT or MRI scans could be performed to confirm/exclude them.

Lauram6123
04-15-2014, 01:09 AM
Okay, Hubby is a Radiologist, so I'm taking dictation.

10% of pheochromocytomas are not in the adrenal glands and are elsewhere in the body. So, if the patient has the laboratory findings and the clinical syndrome, the normal adrenals on the CT do not exclude the diagnosis. So your MC doc would find this out from the radiologist and recommend a nuclear medicine (Octreotide or MIBG) test to find out where it may be elsewhere in the body.