USMLE confusion about the ans to this uw question

[Northerncardinal]

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A 38 yr old man comes to office with frequent bulky, foul smelling loose stools over the past year. he has lost 10kg despite normal apetite. he eats a well balanced diet that includes variety of fruit, vegies, meats, whole grains and dairy products. he has had no recent international travel, works indoors as office manager and has no sick contacts. Past medical hisotry is insignificant, and pt takes no medications. he drinks alcohol occasionally and does not smoke. vital signs and physical exam is normal. what is the most appropriate next step in the workup of this pt's condition?

A. Abdo utrasound
B. colonoscopy
C. jejunal biopsy
D. stool test for ova and parasites
E. stool with sudan III stain
F. vitamin B 12 level

what do u guys think the answer should be?

 

[GODinyou99er]

Celiac disease.?!!!!! C!

 

[Northerncardinal]

the ans is E.

but my confusion is...the vignette clearly points to malabsorption then why do we need to perform Sudan III stool test to screen for malabsorption? do we need to order it everytime we come across a potential case of malabsorption??

 

[tvb]

While I would have picked biopsy too, I guess they are getting at a need to prove indication for the biopsy before doing it? I suppose if you did the biopsy and he ended up not having malabsorption at all you would have jumped the gun.

 

[MissNomer]

but my confusion is...the vignette clearly points to malabsorption then why do we need to perform Sudan III stool test to screen for malabsorption? do we need to order it everytime we come across a potential case of malabsorption??

They are asking for a screening test for malabsorption and Sudan III is the only choice which makes sense as others are either invasive test or are not looking for malabsorption.
So you first need to confirm malabsorption and then take it from there.

 

[Reperfused]

First, it just can't be celiac disease because celiac disease "typically" presents in children less than 2 years of age.
Second, as mentioned above, you always start with a non-invasive test first.
I personally think this question is pointing more towards pancreatic insufficiency, considering the age of the patient and absence of any other findings.