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  #1  
Old 09-14-2011
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GIT Clostridium difficile

Which of the following statements regarding Clostridium difficileľassociated disease relapses is true?
A. A first recurrence does not imply greater risk of further recurrences.
B. Most recurrences are due to antibiotic resistance.
C. Recurrent C. difficileľassociated disease has been associated with a higher risk of colon cancer.
D. Recurrent disease is associated with serious complications.
E. Testing for clearance of C. difficile is warranted after treating recurrences
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  #2  
Old 09-14-2011
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D. Recurrent disease is associated with serious complications.
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  #3  
Old 09-14-2011
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is it D?............
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  #4  
Old 09-14-2011
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B.recurrence due to anbx resistance
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  #5  
Old 09-15-2011
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I think its B.
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  #6  
Old 09-15-2011
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Its. B. . . . . .. . . .
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Old 09-16-2011
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the correct answer is D
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  #8  
Old 09-18-2011
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Quote:
Originally Posted by ricko335 View Post
the correct answer is D
can u explain why D is the correct answer?
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Old 09-18-2011
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very confused
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  #10  
Old 10-19-2014
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A 35-year-old woman underwent a surgery due to a ruptured ectopic pregnancy. On postoperative day 5, while still on a prophylactic antibiotic, she developed malaise, abdominal pain, nausea, anorexia, and watery diarrhea. Pseudomembranous colitis is suspected. Which of the following tests has the highest specificity for the causative organism?

a) Culture on selective medium
b) Cytotoxicity assay
c) Detection of specific antibodies against the organism
d) ELISA
e) Feeding of an experimental animal with the stool filtrate

B.



Watery diarhea with recent ABO use like this case - The antibiotic associated diarhear/C.difficile colitis should be R/O

Since theys ask for 'the most specificity' - The gold standard is stool assay

However, if they ask what to do next - The practical rapid screening tesis stool toxin A,B - which is ELISa to detect pathogenic toxin.

There are nonpathogenic strain of C.difficile made C) less likely

Although A) toxigenic C/S -culture on selective media and test for toxin also provide high specificity but it take too long time for result
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Old 01-18-2015
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Quote:
Originally Posted by ricko335 View Post
the correct answer is D
could you mind to explain us?

thx
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  #12  
Old 01-19-2015
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Quote:
Originally Posted by Trabalista View Post
could you mind to explain us?

thx
Answer to ricko335 question

Its B. Most recurrences are due to antibiotic resistance.

The broadspectrum antibiotics we use to clear of the normal gut flora,this bacteria starts to grow in excess due to its resistance to antibiotics and then cause pseudo-membranous colitis.
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Old 01-20-2015
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Quote:
Originally Posted by CleverFOX View Post
Answer to ricko335 question

Its B. Most recurrences are due to antibiotic resistance.

The broadspectrum antibiotics we use to clear of the normal gut flora,this bacteria starts to grow in excess due to its resistance to antibiotics and then cause pseudo-membranous colitis.
The question talks about recurrences. This means that you got it, possibly due to broad-spectrum antibiotic overuse, took another antibiotic, got rid of C. difficile, and how you have it AGAIN.

Here's why I think it's D.

The normal gut flora is what keeps C. difficile in check.

This is because the gut has a limited number of "slots" to which bacteria can "attach to". If most of those slots are occupied by normal flora, C. difficile doesn't have an opportunity to bind enough to your intestinal mucosa to produce an acute infection. However, if you take an antibiotic that C. diff. is resistant to, it will produce an infection.

I guess if the question asked about recurrence IMMEDIATELY AFTER antibiotic use, then I could see B being the answer. But a random recurrence would indicate that your normal flora isn't thriving well, which could be do to other serious complications.
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  #14  
Old 01-20-2015
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Quote:
Originally Posted by serbanm View Post
The question talks about recurrences. This means that you got it, possibly due to broad-spectrum antibiotic overuse, took another antibiotic, got rid of C. difficile, and how you have it AGAIN.

Here's why I think it's D.

The normal gut flora is what keeps C. difficile in check.

This is because the gut has a limited number of "slots" to which bacteria can "attach to". If most of those slots are occupied by normal flora, C. difficile doesn't have an opportunity to bind enough to your intestinal mucosa to produce an acute infection. However, if you take an antibiotic that C. diff. is resistant to, it will produce an infection.

I guess if the question asked about recurrence IMMEDIATELY AFTER antibiotic use, then I could see B being the answer. But a random recurrence would indicate that your normal flora isn't thriving well, which could be do to other serious complications.
Now that you say it actually makes it clear...

Ok as I am still a student and I didnt even complete micro/path as of yet can you mention what can be actually those complications which get rid of the flora...sorry for my ignorance :P
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Old 01-21-2015
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I'm a student myself, and I havent yet taken Step 1. So Im not sure how correct my thinking was. It was just my logic based on what I know about immunology.
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