Vague NBOME test questions. Check this one out

[Pinkleton]

So I'm looking at the COMAT IM sample questions on their website that have just answers but no explanations, and encountered a question I would like clarification on. It seems like a poorly written question unless I am missing something...

A 25-year-old female presents to the office for a health maintenance examination. She is found to have new-onset hypertension. Family history is negative for hypertension or hyperlipidemia. Physical examination reveals arteriolar narrowing of the optic fundus but no arteriovenous nicking. Serum laboratory studies reveal:
BUN:normal
Creatinine:normal
Sodium:138 mEq/L
Chloride:100 mEq/L
Potassium:3.1 mEq/L
Bicarbonate:29 mEq/L

Urinalysis is normal. The most likely cause of this patient’s condition is

A. atherosclerotic renal artery stenosis

B. Cushing syndrome

C. medial fibroplasia of the renal artery

D. primary aldosteronism

E. renal artery aneurysm

So I narrowed it down to C or D. C would fit with the sex/age of the pt, but the question mentions no bruit. Are we to assume that if it's left out then it is negative? Also, it says BUN/Cr are normal; you would expect them to be elevated at least slightly in renovascular HTN, NO?

I'm trying to figure out how the test writers want us to think, because it seems like both C and D could be correct

---

Members don't see this ad.

 

[Goro]

Absolutely. A very common mistake my students make is adding information that simply isn't there.



I'm trying to figure out how the test writers want us to think, because it seems like both C and D could be correct[/quote]

 

[cliquesh]

Ll

 

[MerickManual]

So I'm looking at the COMAT IM sample questions on their website that have just answers but no explanations, and encountered a question I would like clarification on. It seems like a poorly written question unless I am missing something...

A 25-year-old female presents to the office for a health maintenance examination. She is found to have new-onset hypertension. Family history is negative for hypertension or hyperlipidemia. Physical examination reveals arteriolar narrowing of the optic fundus but no arteriovenous nicking. Serum laboratory studies reveal:
BUN:normal
Creatinine:normal
Sodium:138 mEq/L
Chloride:100 mEq/L
Potassium:3.1 mEq/L
Bicarbonate:29 mEq/L

Urinalysis is normal. The most likely cause of this patient’s condition is

A. atherosclerotic renal artery stenosis

B. Cushing syndrome

C. medial fibroplasia of the renal artery

D. primary aldosteronism

E. renal artery aneurysm

So I narrowed it down to C or D. C would fit with the sex/age of the pt, but the question mentions no bruit. Are we to assume that if it's left out then it is negative? Also, it says BUN/Cr are normal; you would expect them to be elevated at least slightly in renovascular HTN, NO?

I'm trying to figure out how the test writers want us to think, because it seems like both C and D could be correct

Slightly low potassium with low-normal sodium points me towards long-standing primary aldosteronism. Narrow arterioles on fundus exam just points to long-standing nonspecific HTN. BUN/Cr being WNL points me away from answer C.

 

[Pinkleton]

I'm ******ed. I left out that they had the right answer as C

 

[WonderBoy]

I would pick C, because I remember Dr. Sattar (pathoma) speaking about this in his lectures as most common cause of hypertension in young females. But these are the kind of questions you face on comlex, get used to it.

 

[DopaDO]

This is actually not a bad question imo. Everything that you need to answer is right there. I've taken almost all the shelf exams I need to take as a 3rd year and I can promise you there are tons of questions written much worse than this.

 

[MerickManual]

I'm ******ed. I left out that they had the right answer as C

Really? Wow. I guess the "most common reason" was more important than lab values, seeing the hyperplasia is more common than primary aldosteronism. Welcome to the COMLEX.

(and LOL to the resident who also picked primary aldosteronism but edited his response when he was wrong, c'mon man, own your answer!)

 

[cliquesh]

Really? Wow. I guess the "most common reason" was more important than lab values, seeing the hyperplasia is more common than primary aldosteronism. Welcome to the COMLEX.

(and LOL to the resident who also picked primary aldosteronism but edited his response when he was wrong, c'mon man, own your answer!)

I know. I know.

 

[MerickManual]

I know. I know.

😛

 

[Pinkleton]

Really? Wow. I guess the "most common reason" was more important than lab values, seeing the hyperplasia is more common than primary aldosteronism. Welcome to the COMLEX.

(and LOL to the resident who also picked primary aldosteronism but edited his response when he was wrong, c'mon man, own your answer!)

Exactly. I feel like you had to just look at age/gender and pick the most common disease in that age group and ignore the labs

 

[babdoc]

This is actually not a bad question imo. Everything that you need to answer is right there. I've taken almost all the shelf exams I need to take as a 3rd year and I can promise you there are tons of questions written much worse than this.

I agree. Renal artery stenosis is the common type of secondary HTN in young females. It will also cause a bit of a secondary aldosteronism by activating the renin-angiotensin-aldosterone system.

 

[Pinkleton]

I agree. Renal artery stenosis is the common type of secondary HTN in young females. It will also cause a bit of a secondary aldosteronism by activating the renin-angiotensin-aldosterone system.

So you would likely see normal BUN/Cr in these patients that have a form of renal artery stenosis?

 

[babdoc]

BUN and creatinine can be normal in RAS patients. They can also increase, especially in bilateral RAS. It's the aldosterone/renin ratio that you're interested in, which, of course, they do not give you. ;-) Interestingly, if you give an ACEI, creatinine will tend to rise in RAS (more than the normal transient rise when you start an ACEI).

 

[MedicineMike]

Agree with nbome writing some of the worst questions in history. However, this one is fine.

Normal phys exam, normal sodium. They try to throw you off with the k+, but the COMAT would give you high Na in hypoaldost.

 

[MerickManual]

Agree with nbome writing some of the worst questions in history. However, this one is fine.

Normal phys exam, normal sodium. They try to throw you off with the k+, but the COMAT would give you high Na in hypoaldost.

Not always. If it's long standing it will normalize.

 

[MedicineMike]

Not always. If it's long standing it will normalize.

True, but the question states "new-onset"

 

[MerickManual]

True, but the question states "new-onset"

I was saying in regards to questions on the COMAT in general about primary aldosteronism, not about this question.

 

[MerickManual]

Besides "new-onset" means you just caught it, you don't know how long she's had it (as narrow arterioles on funduscopic exam points to longer-standing htn as well)

 

[MLT2MT2DO]

Not always. If it's long standing it will normalize.

It'll still be normal-high, not normal-low.

 

[MerickManual]

It'll still be normal-high, not normal-low.

you're right, my bad. totally misread the number.

 

[Pinkleton]

Agree with nbome writing some of the worst questions in history. However, this one is fine.

Normal phys exam, normal sodium. They try to throw you off with the k+, but the COMAT would give you high Na in hypoaldost.

I assume you mean hyperaldosteronism? And you would have that in both primary (choice D) and secondary (choice C), so I'm not sure you can differentiate by looking at electrolytes

And I believe that you're much more likely to find normal Na in any form of high aldosteronism, because of the aldosterone escape effecting of ANP, right? High/low sodium are caused by shifts in free water, not solutes

 

[babdoc]

Bottom line: any question, COMLEX or USMLE, that involves a young woman with hypertension, medial fibroplasia of the renal artery(ies) should be at or near the top of your list. Electrolytes, etc. are just confirmatory