Can't get over this U World Question! Someone help

[DoctorDude]

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"28 year old man suffers from muscle weakness and periodic headaches. BP is 200/120 and pulse is 90/min. Serum K+ is 3.0 mEq/L. Plasma renin activity is high, as is his urinary aldosterone secretion. Which is a potential cause of this patient's symptoms?"

A) Adrenal Cortical Tumor
B) Juxtaglomerular Cell Tumor
C) Pituitary Tumor
D) Adrenal Medullary Tumor
E) Essential Hypertension

The answer according to UWorld is B.. Which is cool cuz they are going for the hypokalemia thing.. But can anyone tell me why the answer cannot be D? Pheochromocytoma can account for ALL of these symptoms.. Watch: Periodic headaches (very characteristic of pheochromocytoma). High heart rate (due to beta-1 stimulation on the heart). High BP (due to alpha-1 stimulation). High Renin (due to beta-1 stimulation of the juxtaglomerular apparatus). High renin then causes High aldosterone levels. High aldosterone levels cause Hypokalemia. Am i crazy?? Someone help me out here.

Also... B does account for MOST of these symptoms.. but how does it account for the high HR and the periodic headaches?

Would really appreciate help... Thanks!

 

[suji0]

i believe what they are going for, is that renin would usually eventually get low in most other high blood pressure states via negative feedback, but in a juxtaglomerular tumor renin is the actual primary source of the isse

 

[sharklasers]

Hmm I would have chosen B but I do see and understand your reasoning.

The periodic headaches I THINK might be accounted for by the malignant hypertension causing an increase in intracranial pressure? Which is why you get papilledema with malignant hypertension.

And the high HR... I guess it still falls within the normal range? I'm not sure what else.

And I think periodic hypertension is the key presentation of pheochromocytoma. If the stem doesn't say anything about periodic hypertension, I think its always best to not assume that there is some information you don't know!

Also, even though B1 activity stimulates renin release, I think the increase in blood pressure would have some sort of negative feedback as well, decreasing that effect.

Again, all of these are just POSSIBLE explanations. Hopefully someone will chime in and give you more information/correct me if I'm wrong 🙂

 

[coolforschool]

The responses are spot on.

Third paragraph under "Treatment." http://en.wikipedia.org/wiki/Pheochromocytoma

"The patient with pheochromocytoma is invariably volume depleted. In other words, the chronically elevated adrenergic state characteristic of an untreated pheochromocytoma leads to near-total inhibition of renin-angiotensin activity, resulting in excessive fluid loss in the urine and thus reduced blood volume."

 

[DoctorDude]

Alright thanks everyone.. I guess i just read too much into the question! Keep it simple stupid lol

 

[SLC]

Aldosteronoma (Conn syndrome) always presents with low renin. Can't be D.