A simple blood test that can reveal the root cause of your gut problems

A Simple Blood Test That Can Reveal The Root Cause of Your Gut Problems

IBS Smart Test

Being sick is bad enough…

But being sick without knowing WHY or WHAT is causing your symptoms is truly torturous.

And for millions of people with gut health problems, it has been their reality.

  • You’re guessing at the right treatment (and getting it wrong more often than not)
  • Feeling isolated and alone
  • Struggling to explain what’s going on to your family and friends
  • You fear that it could be something really bad – like cancer or an autoimmune disease

This was my story, too: since I was five years old I have struggled with gut problems. I bounced from doctor to doctor and tried every treatment you can imagine (with varying success) before finally being diagnosed with Irritable Bowel Syndrome in 2013 and with Small Intestine Bacterial Overgrowth in 2015.

I know firsthand the pain of undiagnosed gut problems! That’s why I am really excited about a new development in the testing and treatment of gastrointestinal disease that could potentially change this reality for so many people! 

The Problem with Diagnosing Irritable Bowel Syndrome

Until recently Irritable Bowel Syndrome (IBS) was a “diagnosis of exclusion.”

That meant that if you had IBS symptoms like:

  • Constipation
  • Diarrhea
  • Bloating
  • Gas
  • Incomplete or painful bowel movements
  • Mucus in the stool

Your doctor couldn’t diagnose you with IBS until they had ruled out other causes like:

  • Inflammatory Bowel Disease (Crohn’s, Ulcerative Colitis, and Celiac Disease)
  • Food allergies or intolerances
  • Bowel obstruction
  • Gastroesophageal Reflux Disease (GERD)
  • And more…

The process of testing for these other diseases could be costly, risky, and time consuming, including:

  • Elimination diets
  • Allergy testing
  • Colonoscopy
  • Endoscopy
  • CT scans
  • Blood testing

When all those other causes were ruled out, your doctor could finally tell you that you (most likely – not conclusively) had IBS.

My symptoms were so bad I actually ASKED for a colonoscopy! I was in so much pain, I knew there had to be *something* going on. I was devastated when my doctor told me the results of my colonoscopy were totally normal. It gave me the strangest feeling: why am I frustrated that I had a good result on my colonoscopy? (Eventually I was relieved the results were normal, of course.) But at the time all I wanted was a DIAGNOSIS! I wanted a name for what I was experiencing.

Why Has IBS Been A Diagnosis of Exclusion?

Until now, IBS has been a “diagnosis of exclusion” because doctors didn’t know what caused IBS in the first place.

Without identifying the root cause of IBS, they couldn’t test for it – so it had to be diagnosed by exclusion.

That’s how I wound up diagnosed with IBS in 2013: the doctors couldn’t find any other root cause for my bloating, food intolerances, and digestive pain.

But all that has changed thanks to groundbreaking research completed in part by Dr. Mark Pimentel and Dr. Kapil Gupta of Cedars-Sinai Medical Center. They discovered that in a significant number of cases diagnosed as IBS, the root case was food poisoning. (And about 1 in 9 people who get food poisoning then develop IBS!) It’s called post-infectious IBS. (And they’ve created a way to test for it!)

How Does Food Poisoning Cause IBS?

IBS Smart Test

Here’s how the folks at ibs-smart™ explain it:

It has to do with a toxin called Cytolethal Distending Toxin B, or CdtB for short. It turns out that every one of the most common bacteria that cause food poisoning releases CdtB.

When a toxin like CdtB enters your body, your immune system fights back with an antibody – in this case, anti-CdtB.

Anti-CdtB can confuse your body into developing another antibody called anti-vinculin. This harms a naturally occurring protein in your body called vinculin that helps cells migrate and connect to each other.

This is an autoimmune response and leads to gut nerve damage and improper functioning of the Interstitial Cells of Cajal (ICC) and Migrating Motor Complexes (MMC), which regulate the contractions of your gut.

This can ultimately result in Diarrhea-Predominant and Mixed-Type (Diarrhea with Constipation) Irritable Bowel Syndrome, sometimes many years after the initial infection.

That means anyone who has ever eaten a questionable salad or sandwich that sat out too long is at risk of developing IBS! (Even if you haven’t had food poisoning in years.)

Understanding the root cause of IBS allowed these brilliant doctors to create a test for it…

Does This Test Work for SIBO Too?

I knew you’d ask that!

The answer is a bit complicated.

There is so much overlap between Small Intestine Bacterial Overgrowth and IBS. Dr. Steven Sandberg-Lewis says 75% of people with IBS have SIBO. And we know food poisoning is a major root cause of SIBO too.

That means you could have post-infectious IBS and SIBO. (I did!) I was tested and sure enough – I was positive for post-infectious IBS. 

Bottom line: whether you’ve been diagnosed with SIBO or IBS – or neither one yet! –  I think this test is incredibly valuable. It can change your entire path of healing.

The Blood Test for Irritable Bowel Syndrome

It’s a simple blood test your doctor orders for you – and it can definitively tell you if you have post-infectious IBS.

It works by measuring levels of the anti-Cdtb and anti-vinculin antibodies in your blood. High levels of these antibodies is a sign you have post-infectious IBS.

It’s called ibs-smart™.

Why This Is So Important

Knowing your root cause can save you years of uncertainty, potentially risky medical procedures, medications you don’t need, and a lot of heartache.

Personally, once I knew *for sure* that I had post-infectious IBS, it was like things clicked in my brain. I knew the post-infectious IBS was causing issues with my motility -so I finally started using a prokinetic religiously. BINGO – a huge reduction in symptoms for me.

Knowledge is power!

Get The Test (At A Discount with Online Prescription)

And even MORE good news – now you can order the test kit with an online prescription and get answers right away!

Get 25% off your ibs-smart™ test here! IBS Smart Test by using the coupon code “sibosos2021” upon checkout

Outside the United States? Go here to get the test: Get an IBS blood test internationally

Then pop into the comments and tell me what you think. Do you have (or suspect) post-infectious IBS? 

There has been so much buzz about this test in the SIBO SOS™ community and on Facebook, so I wanted to get accurate info about this test out and set the record straight. I hope this was helpful to you!

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22 thoughts on “A simple blood test that can reveal the root cause of your gut problems”

  1. How can I obtain a Transcript of Dr Mark Pimentel’s talk, entitled “Digestive Disease Week 2022
    Update for SIBO, IMO, and IBS?” I would like to provide a copy of it to my Gastroenterologist. Thank you very much.

  2. Very intrigued by the IBS Smart test. Having some difficulty finding info in how it applies regarding the distinction between SIBO and IMO. Personally having methane-dominant SIBO (or technically IMO now) I’m wondering if this test would be applicable for me? Most of what I read mentions IBS-D, but it also lists SIBO. Do you have any insight on whether these markers of anti-CdtB and anti-vinculin also apply to methane / IMO? Thanks so much!

    1. Hi Matthew,

      Yes, you’re absolutely right! Unfortunately, it’s mostly recommended for IBS-D and IBS-mixed! And the reason is that Dr. Pimentel says that they just don’t find these blood biomarkers for autoimmunity in IBS-C and that what they find is that the “pathophysiology of IBS-C is different.”

      Keep on searching, SIBO warrior. It sounds like you’re down to finding your underlying root cause! You’ve got a bit of investigative work to do and I can appreciate the enormity of that task. If you ever think we can help in any way, we’re here and we’ll try our best to help you navigate all these overwhelming amount of information. We’ll be around!

      1. So, if you have had food poisoning, you more likely to experience diarrhea problems? I’ve had diarrhea but am constipation dominant.

        1. SIBO SOS® Support

          Hi Julie,

          Hmmm… that’s tricky! I’m almost tempted to suspect you’re probably in the IBS-mixed group – “mixed” meaning you are alternating between diarrhea and constipation.

          I think you could request a call from the ibs-smart™ support desk. They should be able to tell you if you might be a good candidate for the test.

          Good luck!

  3. So what’s the treatment plan if you test positive? It’s great to know the root cause but having steps to fix it is what is really needed…

    1. Hi Hailey! We recently did a webinar with Dr. Siebecker where she walked us through her 9-step SIBO recovery protocol. If you can carve out some time to watch it, you can find it here: SIBO Recovery Roadmap. I hope that helps!

  4. we couldn’t have said it better! appreciate you chiming in! To everyone else, please watch the video! Ani was brilliant at explaining it!!!

  5. What are some good prokinetics that you used successfully for help now? I know I react to foods, with an autoimmune, response, vs. an allergy just not sure always what it was, and then get constipated as a result.

    1. Hi Lyn,
      Dr. Allison Siebecker mentions 6 prokinetic options. Three are pharmaceuticals… namely low dose erythromycin, low dose prucalopride, and low dose naltrexone (LDN). And then, herbally, it would be Iberogast, MotilPro or just ginger root (straight ginger).
      She actually has an entire masterclass on just prokinetics alone if you want to look that up here: Using Prokinetics for SIBO Treatment & Prevention.

  6. What if your GI dr confirms Hydrogen SIBO and wants further testing like MRI to detect anatomical abnormalities and extensive blood tests to determine immunodeficiency. Is she on the right tract?

    1. Hi Kim,
      Anatomical or structural abnormalities is one of the many potential underlying causes of SIBO, absolutely. And yes, there are markers to watch out for in blood tests that could spell autoimmunity!
      It does sound like your GI is working not only to resolve your SIBO, but he/she is being really proactive with finding what might be causing the SIBO too! That’s wonderful to hear actually since at least two-thirds of SIBO cases are actually likely to relapse! So you can resolve the SIBO, but get right back into it anyhow if you don’t address those underlying causes!
      Good luck! It’s sounding to me like you and your GI have got some investigative work cut out for you!!!

  7. Looks v interesting but does it change the course of treatment if you know you have SIBO/IBS? If you’ve got a postitive SIBO test what’s the additional benefit from having this test (apart from knowing you need motility agents long term etc – which you know you do if you have SIBO anyway?)

    1. Hi Helen, we believe so!! That’s why Shivan was so intent in getting a collaboration together with ibs-smart for us all! Yay!!

      But if you want the tiny nuances of why we think it impacts treatment, scroll up please and watch the video! It’s definitely gonna be worth the 30 minutes! Ani prefaced the whole presentation with answering exactly that question!

      Good luck 🙂

    1. Hi Kristie! Not necessarily – it really depends on each person. That being said, even if you do have ‘chronic SIBO’ that doesn’t mean you can’t put it in remission and keep it there (even for long periods of time) – so don’t give up hope!

  8. Great information, I’ve been struggling for years with gut / constipation issues,
    I have just been diagnosed by mri with
    Severe extensive sigmoid diverticular disease
    What are your thoughts??
    Thanking you,

    1. Glad you found the information useful. And it sounds like you have a diagnosis. Not sure I can offer you any thoughts here. This question is best answered by your physician. I hope you’ve found the key to unlock your years of struggling. Good luck with your journey and be well.

    2. Lori, I like you have struggled for years with the same gut/constipation issue and just recently got a GI Doc to do the breath test and I have Hydrogen SIBO. I have a family history of intestinal issues and my mother’s two sisters died post surgery of “intestinal blockages”. Do not give up. I have found most GI Doctor’s will ignore your complaints or if you insist give you a “test” (ie: breath test) a diagnosis of SIBO and a prescription for antibiotics with no follow up at all. Sivan wrote a book that is well worth buying! You have my sincere sympathy. I am still struggling to get help. Linda Q

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