C. diff. Testing and Diagnosis

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Bobbie
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Re: C. diff. Testing and Relapsing - Latest Info.

Postby Bobbie » Wed Dec 24, 2014 12:47 am

Latest info. On Testing and Relapsing

I asked a C. diff. expert these questions as many docs. disagree. I trust his answers above all others.

Q. How long to retest after Flagl/vanco/Dificid during active C. diff.?
A. 7 to l4 days and the longer the better. PCR is false positive for up to two weeks as bits of DNA from killed C. diff. are passed out, and if tested too soon gives a false positive result. Culture early is accurate but not easy to get done by labs.

Q. When to have FMT?
A. After two or three rounds of C. diff. meds.

Q. Is PCR most accurate test?
A. Yes, with above condition.

Q. Do the spores/bacteria lie dormant in your system until another antibiotic/or other cause activate them?
A.Yes, spores do lie dormant -- that is the underlying mechanism of the "relapsing" nature of the disease togethre with the damage to the host microbiota.

"BUT after FMT there are no longer any spores left and antibiotics will not cause a relapse. The reason we use FMT is that the incoming new bacteria possess bacteria which secrete 'antibiotics' that kill the spores.

Relapse after successful FMT generally requires antibiotics + exposure to a new source ( generally different strain) of CDI."

The expert said, "..The best test of FMT in CDI is a course of antibiotics without recurrence. Works if well done. I routinely do 2 infusions. First via colonoscopy next day enema. Get close to 99% cure. Then the patient is GENERALLY safe . Exceptionally (3-5%) antibiotics + close exposure to a new strain eg in hospital .. Will give them another CDI infection.
... So around antibiotic time keep out of hospitals, keep away from sick people, wash hands , no cold meats , pray lol."


So, wash your hands, try to avoid antibiotics (if that is your "trigger"), and know someday soon, with all the new knowledge, treatments, and additional testing, C. diff. will be a disease of the past - like so many others: bubonic plague, polio, small pox, etc - or at least easily treatable. Remember, you aren't necessarily part of this category. Many (the majority) recover from C. diff. easily and never have it again.

Also in Gen. Dis.

roy
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Re: C. diff. Testing - Includes Most Recent Info.

Postby roy » Thu Jan 22, 2015 4:08 pm

This article talks about reliabilty of tests

PAY PARTICULAR ATTENTION to the sections on the right of the pages that prove that testing to prove a cure after meds are up to 50% false positives.

http://www.stmarysmadison.com/physician ... 202013.pdf

Bobbie
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Re: C. diff. Testing - Includes Most Recent Info.

Postby Bobbie » Wed Feb 04, 2015 12:53 am

Contrary to many doctors' opinions, a c diff expert told me recently c diff can be present with constipation instead of the usual,"profuse, watery diarrhea." If you feel you have c diff with this symptom, trust your "gut feeling" and pursue it. Many labs will not test stool samples if they are solid. Call around and find out which labs do.

roy
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Re: C. diff. Testing - Includes Most Recent Info.

Postby roy » Wed Feb 04, 2015 2:43 pm

Any lab will test solid stool if the Dr puts in a specific request and states that they want the solid sample tested.

Bobbie
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Re: C. diff. Testing - Includes Most Recent Info.

Postby Bobbie » Wed Mar 04, 2015 2:43 am


Bobbie
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Posts: 12140
Joined: Sat Aug 06, 2005 8:00 pm

Re: C. diff. Testing and Diagnosis

Postby Bobbie » Wed Apr 15, 2015 2:08 am

Tonya donated this info ater she called about the results of her PCR test.

They had done a PCR for toxinogenic C Diff and a test specifically for the NAP27 strain and both were negative.
Incidentally, just for confirmation and clarification, I asked her (....
Director of Clinical Trials, at the)....exactly what the PCR test looked for. She told me it looks for the organism itself - the c diff bacteria and looks for the gene in its DNA that tells the bacteria to produce the toxins. I asked her if the PCR test would detect the spores. She said, "yes." I also asked if it would detect the presence dead bacteria. She said, "yes." She confirmed that it does not test for the toxin itself. The C Diff does not need to be producing any toxin at all to be detected. She further explained that this was why they don't like to test someone with no symptoms...even someone in the 'carrier' state, whose spores are completely dormant, will return a 'positive' test result. No test is 100 per cent but the PCR Iis one of the most accurate so far.

Bobbie
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Re: C. diff. Testing and Diagnosis

Postby Bobbie » Tue Jan 05, 2016 2:13 am

I asked a doc,who is a C diff expert, several questions people have posted lately. Here are the answers. I trust this doc above all others when it comes to c diff. Would not mention where you got this info as it could be construed as medical advice - not in our job description.

ANSWERS

Ask post-FMT people to avoid PCR and delay at least till week 8. Too many false positives. ( DNA not living CDI)

Best way to measure success is "has the diarrhea gone?"... Then 8 wk PCR. If solid add saline and make it liquid.

I don't know what "invalid" means. Change labs. Complain ! (Bea, this should help you.)

Yes, you can be +ve for CDI with formed stool. Generally such patients have cramping or gas. Some have co-existing constipation.

Bobbie
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Re: C. diff. Testing and Diagnosis

Postby Bobbie » Sat Sep 10, 2016 5:35 pm

Re: Documents and links we can refer posters to
Postby roy » Sat Sep 10, 2016 11:52 am

Molecular Tests Linked to C difficile Overdiagnosis
Janis C. Kelly
September 11, 2015

Another version can also be viewed here

http://archinte.jamanetwork.com/mobile/ ... id=2434732

Thx, Roy.


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