gastroenterology q9 - USMLE Forums
USMLE Forums Logo
USMLE Forums         Your Reliable USMLE Online Community     Members     Posts
Home
USMLE Articles
USMLE News
USMLE Polls
USMLE Books
USMLE Apps
Go Back   USMLE Forums > USMLE Step 3 Forum

USMLE Step 3 Forum USMLE Step 3 Discussion Forum: Let's talk about anything related to USMLE Step 3 exam


Reply
 
Thread Tools Search this Thread Display Modes
  #1  
Old 05-20-2013
USMLE Forums Master
 
Steps History: 1+CK+CS
Posts: 720
Threads: 217
Thanked 552 Times in 309 Posts
Reputation: 562
Default gastroenterology q9

A 54-year-old male presents with 1 month of diarrhea. He states that he has 8–10 loose bowel move-ments a day. He has lost 4 kg during this time. Vital signs and physical examination are normal. Serum laboratory studies are normal. A 24-hour stool collection reveals 500 g of stool with a measured stool osmolality of 200 mosmol/L and a calculated stool osmolality of 210 mosmol/L. Based on these findings, what is the most likely cause of this patient’s diarrhea?

A. Celiac sprue B. Chronic pancreatitis C. Lactase deficiency D. Vasoactive intestinal peptide tumor E. Whipple’s disease
Reply With Quote Quick reply to this message



  #2  
Old 05-20-2013
XpaezX's Avatar
USMLE Forums Master
 
Steps History: 1+CK+CS+3
Posts: 1,216
Threads: 41
Thanked 1,327 Times in 711 Posts
Reputation: 1342
Default

Quote:
Originally Posted by cingulate.gyrus View Post
A 54-year-old male presents with 1 month of diarrhea. He states that he has 8–10 loose bowel move-ments a day. He has lost 4 kg during this time. Vital signs and physical examination are normal. Serum laboratory studies are normal. A 24-hour stool collection reveals 500 g of stool with a measured stool osmolality of 200 mosmol/L and a calculated stool osmolality of 210 mosmol/L. Based on these findings, what is the most likely cause of this patient’s diarrhea?

A. Celiac sprue B. Chronic pancreatitis C. Lactase deficiency D. Vasoactive intestinal peptide tumor E. Whipple’s disease
I dont understand.. I may sound stupid.. for what I see the stool osmolal gap is less than 50 .. (it is 10 to be exact).. no history is given that specific meals cause the symptoms.. and the patient is losing weight.. I will pick VIPoma as the answer..
Reply With Quote Quick reply to this message
The above post was thanked by:
cingulate.gyrus (05-20-2013)
  #3  
Old 05-20-2013
USMLE Forums Master
 
Steps History: 1+CK+CS
Posts: 720
Threads: 217
Thanked 552 Times in 309 Posts
Reputation: 562
Default

Quote:
Originally Posted by XpaezX View Post
I dont understand.. I may sound stupid.. for what I see the stool osmolal gap is less than 50 .. (it is 10 to be exact).. no history is given that specific meals cause the symptoms.. and the patient is losing weight.. I will pick VIPoma as the answer..
Exactly u r correct......Great.....
The answer is D.

This patient has a stool osmolality gap (measured stool osmolality - calculated stool osmolality) of less than 50 mosmol/L, suggesting a secre-tory rather than an osmotic cause for diarrhea. Secretory causes of diarrhea include toxin-mediated diarrhea (cholera, enterotoxigenic Escherichia coli) and intestinal peptide–mediated diarrhea in which the major pathophysiology is a luminal or circulating secretagogue. The distinction between secretory diarrhea and osmotic diarrhea aids in forming a differential diagnosis. Secretory diarrhea will not decrease substantially during a fast and has a low osmolality gap. Osmotic diarrhea will generally decrease during a fast and has a high (>50 mosmol/L) osmolality gap. Celiac sprue, chronic pancreatitis, lactase deficiency, and Whipple’s disease all cause an osmotic diarrhea.
Reply With Quote Quick reply to this message
The above post was thanked by:
XpaezX (05-20-2013)



Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the USMLE Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:
Medical School
Choose "---" if you don't want to tell. AMG for US & Canadian medical schools. IMG for all other medical schools.
USMLE Steps History
What steps finished! Example: 1+CK+CS+3 = Passed Step 1, Step 2 CK, Step 2 CS, and Step 3.

Choose "---" if you don't want to tell.

Favorite USMLE Books
What USMLE books you really think are useful. Leave blank if you don't want to tell.
Location
Where you live. Leave blank if you don't want to tell.

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes


Similar Threads
Thread Thread Starter Forum Replies Last Post
Gastroenterology q6 cingulate.gyrus USMLE Step 3 Forum 6 05-26-2013 12:42 AM
Gastroenterology q7 cingulate.gyrus USMLE Step 3 Forum 2 05-20-2013 09:54 AM
Gastroenterology q8 cingulate.gyrus USMLE Step 3 Forum 2 05-20-2013 09:26 AM
Gastroenterology q5 cingulate.gyrus USMLE Step 3 Forum 2 05-19-2013 12:27 PM
gastroenterology q4 cingulate.gyrus USMLE Step 3 Forum 10 05-19-2013 12:08 PM

RSS Feed
Find Us on Facebook
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.

USMLE® & other trade marks belong to their respective owners, read full disclaimer
USMLE Forums created under Creative Commons 3.0 License. (2009-2014)