Are We Defining SIBO Properly?

Intro:

Welcome to Dr. Ruscio radio, providing practical and science-based solutions to feeling your best. To stay up to date on the latest topics as well as all of our prior episodes, make sure to subscribe in your podcast player. For weekly updates visit DrRuscio.com. The following discussion is for educational purposes only and is not intended to diagnose or treat any disease. Please do not apply any of this information without first speaking with your doctor. Now let’s head to the show.

DrMichaelRuscio:

Hi everyone. Welcome back to another episode of Dr. Ruscio radio. I’m excited for today because we get to nerd out on an assortment of concepts from the past few months of our Future of Functional Medicine Review clinical newsletter. I’m really proud of the FFMR. In writing the newsletter now for a number of years, it’s been very encouraging to see that I can write about a concept in the newsletter, other doctors can read it and apply some of the concepts in their practices and then produce similar results. It’s this pseudo external validity, meaning that these things are not just dependent upon me and how I’m looking at things. You could even argue that having a podcast gives you a little bit more of a placebo effect. That additional placebo that’s garnered by having some visibility online could allow me to have results that are unique to me only because of that placebo.

DrMR:

That would be a fair criticism. The fact that other clinicians are able to replicate this really shows me that there is something efficacious here. So I’m very proud of the newsletter. We run a promotion once or twice a year for people who have not yet joined the newsletter, but who may be thinking about it to make it easy for them to have a look, see if it resonates, and if it is beneficial and insightful. That’s what we’re doing for the month of April. For just $1, you can get all access for the entire month of April. You not only have the current newsletters, but also the backlogs. So there is a lot of information there that you can read through. You can learn from case studies, from research reviews. These are really the main tools that we try to use to teach. The case studies, which is where everything comes together into application. Also taking a research study, which may take anywhere from 30 to 60 minutes to read and take notes on, and then distilling it down to the most important bullets as cogently as possible so that you can, in five minutes, take away all the information from a research study rather than having to spend 30 to 60 minutes extracting all that yourself. So remember the newsletter is there as a resource. If you go to DrRuscio.com/review, you can learn a little bit more and plug in for $1 for your first month of all access.

DrMR:

Today we’ll be talking about a number of things. The first is a case study. This is actually from one of the clinicians, Dr. Robert Abbot, who is now part of the practice, the Austin Center for Functional Medicine, which is the new name that my clinic is operating under. The case study is regarding pediatric hypothyroidism. Previously functional medicine had failed the individual and the appropriate and careful use of T3 was actually a game changer. We’ll go into some of the details here. We’ll also cover a research study summary on the small intestinal microbiota and underlying dysbiosis that may be the cause of functional gastrointestinal disorders. Functional gastrointestinal disorder is a broader umbrella term under which we can classify IBS, GERD, and some other conditions that may affect about 40% of the US population. Also in this study, we’ll highlight the differences between small intestinal dysbiosis versus SIBO (Small Intestinal Bacterial Overgrowth), which is also important. Then we’ll also look at another study that looked at and correlated breath testing and small intestinal d aspirates.

DrMR:

So let’s jump in and start with the case study. This case study originally comes from the September, 2020 Future of Functional Medicine Review clinical newsletter, and it’s entitled “Case Study Pediatric Hypothyroidism and Gut Dysfunction Combining Traditional and Functional Approaches. And so in this case, the patient was a seven year old male with a history of developmental delay, hypotonia hypothyroidism, and within one year of life he continued having worsening thyroid labs, increasing TSH, despite being on T4 medication in the context of functional medicine care. The primary symptoms were constipation and the neuro cognitive failure of failure to thrive. Poor school functioning mainly and also food allergies and food reactivity. And the mother is well-educated in regards to health and currently was following a paleo diet. Now the initial blood chemistry showed a TSH (Thyroid-stimulating hormone) of 7. This is a high TSH paired with a high reverse T3 and a high T4. Kind of a paradoxical set of findings here. Total T3 was normal, free T3 was normal, and the TPO antibodies were normal. So we’re seeing this high TSH plus high T4 in a high reverse T3. So this is a very anomalous pattern.

DrMR:

And the initial differential includes thyroid insensitivity versus impaired conversion of T4 to T3, a potential Ts OMA or a TSH secreting tumor, or potentially some type of pituitary dysfunction. So the main clinical question here that Dr. Abbott is pondering is can I treat this child? He has already been working with functional medicine providers – what else can I offer? Which is I think a fair question. So one of the things that Robert discusses here, and I think this is a very important insight is not everyone may be comfortable treating children. And that’s something that’s gonna depend on your training, your background, your interests, but the purpose of the newsletter is to document the care of our patients. Often those whom have been treated by multiple functional medicine providers without any benefit or resolution. And we’re trying to provide people a model of thinking and application.

DrMR:

This is in order to be able to help these patients, which may otherwise be intimidating. So the clinical approach here, and some of the clinical questions are: why would TSH keep rising in a setting of being on T4 medication, recognizing the child has overt gut symptoms and not overlooking the gut thyroid connection research, potential reasons for the T4 T3 disparity issue that we’re seeing here rule out rare, but more serious conditions treat what you see the gut and allergies and explore safe clinical treatment to address thyroid dysfunction, T3 medication trial, and how will this potentially impact TSH? The treatment here was to decrease T4 medication and to start on 2.5 micrograms of T3. The follow-up testing revealed that the TSH was now 3.74. So now the TSH has gone from high, down into the normal range. Now this is where being a bit precise with the levels is warranted.

DrMR:

Meaning there’s general agreement that a TSH at or below 2.5 should really be the target. That is the TSH suppressive target of medication. Note – this is oftentimes misrepresented in functional medicine-ville, proclaiming that people who are not on medication should natively have a TSH below 2.5 and a huge, in my opinion, egregious mistake is occurring in the field in claiming that people who have normal endogenously occurring TSHs of above 2.5 should start on medication. In this case, in this setting of a patient on medication, that is when a TSH goal of 2.5 or below is warranted. So here we’ve made some noteworthy improvement from abnormally high – now down to in the normative range of 3.7. This may not be ideal, but certainly a great start. And the remainder of the panel has also normalized –  Free T4 is 1.57, Total T4 is 11.3, Free T3 is 3.6, Total T3 is one 35.

So we went from a TSH of 7 down to a TSH of 3.7, with the addition of T3. This also overlaps with the thyroid algorithm that we’re developing, which you can access once you’re a member of the FMR.  You can click through and read our thyroid algorithm, which is slowly and steadily evolving over time and with new data emerging all the time, but essentially the recommendations there – to state it briefly – are to start on T4 monotherapy. And then if an individual is not responding, consider one of two things; improving or addressing gut health, because malabsorption can be an issue; and also, consider a trial on T3. So in this case, this is where it’s now warranted. And I just want to highlight that because I’ve often been critical of the over-use of T3, but it doesn’t mean that I’m absolutely opposed to the use of T3.

DrMR:

It’s just, unfortunately T3 is often used prematurely. We want to be using T3 at the right time, hence the kind of algorithmic or hierarchical approach.  The initial dose of 2.5 micrograms of T3 seems to have helped normalize the TSH. There are no signs of pituitary dysfunction or tumor on other testing. The thyroid ultrasound also returns as normal. He appears to have some slight iron overload and elevated eosinophils that are worth following up and addressing. And that shouldn’t be too surprising given some of the inflammatory symptoms he’s also exhibiting. So at this point, we’re moving in the right direction. We’re seeing that the TSH, which was the most concerning lab value start to rectify, and the following changes were then made to his care plan; the addition of probiotics, the addition of gut repaired nutrients, a mass cell support, and an increase of T3 to five micrograms leading to a clinical outcome and some conclusions.

DrMR:

These are: testing thankfully did not reveal more serious and rare concerns behind the thyroid dysfunction; increasing the amount of T3 improved the TSH; probiotics – the gut repair nutrients in the mass cell support resulted in improved constipation, less allergic reactions and correlated in nutritional labs and markers or improvements; nutritional labs and markers of immune functions, namely the eosinophils. So this iterative cost effective model without excessive testing and hitting these simple fundamentals of proper execution of the thyroid algorithm helped to vector T3 at the appropriate time, but also paying attention to one’s gut health and how support there led to resolution of the other symptoms. So this is a great case study of how an otherwise intimidating looking case when thought through in this kind of stepwise hierarchical and algorithmic approach led to a great outcome.

SponsoredResources:

Hey everyone, this is Dr. Ruscio with a quick note about immunoglobulins. If you haven’t yet tried immunoglobulin therapy, I hope you will try our Intestinal Support Formula. To make it a little easier for you to do so, we are running a promotion of 10% OFF if you go to our website, drruscio.com/isf you can use the code TryISF. What’s novel and unique about immunoglobulins is they seem to attenuate immune system overzealousness in the gut by glomming onto and kind of deactivating, almost like taking a shard of glass and covering it with wax, against toxins and bacterial fragments like LPS. What ends up happening is instead of these fragments triggering an overzealous immune system, causing inflammation, exacerbating leaky gut, leading to a whole array of different things like dysbiosis, food reactive brain fog or bloating, that cascade is attenuated by the immunoglobulins. Perhaps the best study looking at this was the one by Weinstock that found a 75% response rate, albeit uncontrolled, in patients who did not respond to diet, who did not respond to Rifaximin, who did not respond to antispasmodics. Certainly an exciting and novel therapy. If it’s not one that you’ve tried, or if you want to try it again, go and check out our Intestinal Support Formula, use the code, TryISF for 10% OFF.

DrMR:

So moving on to a study review from October, 2020, entitled “Small Intestinal Microbial Dysbiosis Underlies Symptoms Associated with Functional Gastrointestinal Disorder.”

A few notes here, the majority of microbiome studies focus on stool, while the small intestinal microbiome remains relatively unexplored. This is something that I discussed in my book “Healthy Gut, Healthy You” (more details at https://drruscio.com/gutbook/), it’s a very important concept. It provides a mooring preventing us from falling into too much speculation based upon interesting stool testing.  Nonetheless, it’s something that gives us an incomplete picture of the gut. So we don’t want to fall into this hubris of thinking that just because we’re seeing certain things on healthy versus disease populations on stool testing, that’s going to give us all of the clinical interventions that may help those people.

 

One of the key questions here are symptoms associated with SIBO, and, can a quantitative definition of SIBO or something else, perhaps dysbiosis, explain match symptoms in a cohort of individuals? To quote the intervention here, we characterize the small intestinal microbiota of patients with GI symptoms, undergoing testing for SIBO. We found significant alterations in the small intestinal microbial composition, especially in a subset of symptomatic patients.

 

Here’s some of the key findings here.  We show that SIBO (based on culture, not on a breath test) based on duodenal aspirate culture that reflects an overgrowth of anaerobes, does not correlate with patient symptoms, and may be a result of dietary preferences. Importantly, small intestinal microbial composition on the other hand is significantly altered in symptomatic patients, and does not correspond with aspirate culture results. So I said more simply SIBO, as defined by a culture, did not correlate with symptoms and may have been a result of dietary preferences.  But this disruption of microbial composition, more loosely termed dysbiosis, did correlate with patient symptoms.

DrMR:

So there is an important delineation here that shows us that culturing for SIBO -while some will say that this is the gold standard – may not always correlate with symptoms, which is one of the reasons why I always harp on making sure that we put clinical outcome above mechanism, right? Because in this case, what may be happening is the definition of SIBO may not capture all symptomatic patients.  That shouldn’t be surprising, or perhaps now that we’re learning about the third type of gas, hydrogen sulfide, SIBO, perhaps incorporation of that into the analysis will have altered the finding. At the end of the day, the clinical decision-making process should be centered around clinical symptoms. And asking the question, “Does a given test help identify and distinguish those who have symptoms from those who do not?” And outside of even the hydrogen sulfide piece, there may be this entity, as this study is suggesting, that is not dependent upon overgrowth, but as more a disruption of the balance, ie dysbiosis.

DrMR:

Some of the clinical takeaways from this paper, SIBO is NOT the same thing as small intestinal dysbiosis, for which we really don’t have any readily available test for small intestinal dysbiosis.  Patients with clinical symptoms of SIBO may actually have small intestinal dysbiosis and not SIBO as defined by current definitions.  Treatment should likely not be dependent on the formal definition of SIBO or even a SIBO breath test.

DrMR:

It’s important that we don’t limit how we treat a patient based on testing exclusively. Does that sound familiar? Something I’ve been saying for quite a while.  This is really, in my opinion, an evolution of, at first, and especially when I was new in practice, I wanted to try to be as scientific as possible. And I certainly didn’t want to feel like I was a heretic, because to be honest with you, I felt like there was a lot of heresy around me where I would speak with people and everyone was jazzed about what they were doing, but no one seemed to be at all critical. And so this is where I think for many of us, the testing has the appeal. I don’t want to be heretic. I want to be evidence-based. I want to be scientific.

DrMR:

So, I’m going to do the tests. I’m gonna treat the labs. That’s a pretty sound case, but it breaks down when we start realizing that the tests aren’t perfect. And while the tests can reveal some things, they can’t reveal all things. So there’s this blending of testing plus empiricism. And this is why I say that testing is one third or one fourth of the data needed to make a decision.

How would this translate into clinical practice? Would we not use any of the “SIBO treatments” for someone who was exhibiting digestive symptoms, even SIBO like digestive symptoms, but had a negative SIBO breath test? In my opinion, no, we would still use anti-microbial therapy, probiotics, immunoglobulins, elemental dieting, all these are viable when understanding and operating underneath the construct of “I’m not going to limit my therapeutic intervention solely to what the tests are saying.”

DrMR:

This is sometimes difficult for patients to wrap their heads around because, and understandably so, when you’re not feeling well, you want a thing to be able to say, it’s THIS thing that is causing my problem. And that’s why I think the diagnosis of SIBO is so alluring to many because I’m a person in the world having symptoms, not feeling well. I’d love to point my finger at what it is that is causing them, but it’s not always that simple. And this is why I repeatedly have the conversation in the clinic that yes, while testing can be revelatory, it doesn’t give us every insight that we need and why I look at your gut and your gut ecosystem more as a garden. And I know that may sound a little bit kind of aethereal and hippy dippy and in terms of the analogy, but it holds true clinically meaning we can manipulate all these variables to try to make the health of the soil –

DrMR:

that is your garden – as healthy as possible. There’s not necessarily a test for every one of these. So we use a test to some extent, but we also make some interventions with the soil, the amount of sunshine, the amount of rain, the amount of fertilizer, the amount of shade, a degree of weeding here and there. And we tend to the garden, we observe the health of the soil and the health of the growths from that soil to help us hone in more fully on what this ecosystem needs. So while on its face, it may sound a bit non-scientific, but it actually leads to much more clinically efficacious care. So that was an insightful study. The main takeaway is disruptions and problems in the small intestine shouldn’t be looked at solely through the lens of SIBO (yes or no), overgrowth (yes or no). There can also be this dysbiosis, which we don’t really have a way of testing other than doing a digital aspirate, which, shoving a tube down someone’s nose or throat is not something that’s able to be done routinely in clinical practice.

DrMR:

So we want to use the treatments that we know, or at least we think can help with dysbiosis, using someone’s symptoms as a barometer of, “are we helping with what is perhaps presumed dysbiosis and within the same theme from the November, 2020 FFMR” where we did a rapid review, meaning a short review.  So in the newsletter, some studies are worth a further elaboration than others. For some, we give an ultra-concise review known as a rapid review. So this was from November, 2020, the title of this case study we reviewed here rapidly was, “Does a Glucose-Based Hydrogen and Methane Breath Test Detect Bacterial Overgrowth in the Jejunum”. And the takeaway here was that SIBO breath testing, in keeping with the same theme, did not adequately correlate with juvenile sampling, also showing overgrowth. So the SIBO breath test for overgrowth, small intestinal bacterial overgrowth, did not tightly correlate to taking a direct sample from the jejunum and showing overgrowth, but it did show disruptions of balance or dysbiosis.

DrMR:

This is even more evidence as we’re learning more about these different ways of assessing what’s going on in the small intestine, and we’re seeing that yes, there is evidence showing that those with SIBO breath test with a positive result are more likely to have symptoms – that’s been shown in meta-analyses. And there have been studies showing that mainly in the model of using Rifaximin, that treatment with antibiotics will produce improvements in the SIBO testing that will track with symptoms.  So pre/post SIBO breath test using Rifaximin as the intervention, post-intervention SIBO breath test improves, and that correlates with IBS symptom inventories improving, but it’s not perfect. And it doesn’t account for every patient for every case. And there’s probably patients listening to this or clinicians who are reflecting back on patient cases, listening to this saying, yes, clearly I’ve seen individuals who are negative for SIBO, but still exhibit all the symptoms we typically associate with SIBO.

DrMR:

Again, part of that could be, now we have the ability to test for hydrogen sulfide. However, we don’t want to put all of the eggs in the hydrogen sulfide basket and kind of honor and understand that there’s different ways. Things can go askew. It’s not just overgrowth or no overgrowth. There can be disruptions in the balance. And that’s what this study is also supporting. What this does is hopefully coaxes the clinician into a heuristic that integrates much more of the patient’s symptoms and how they respond to therapeutics given empirically rather than solely guided based upon objective markers. The objective markers have their time and their place, but we don’t want to make the lab values the only thing that help us guide our treatments.

RuscioResources:

Hi everyone. This is Dr. Ruscio. In case you need help, I wanted to quickly make you aware of what resources are available to you. If you go to drruscio.com/Resources, you will see a few links you can click through for more. Firstly, there is the clinic, which I’m immensely proud of. The fact that we deliver cost-effective, simple, but highly efficacious, functional medicine. There’s also my book, Healthy Gut, Healthy You, which has been proven to allow those who’ve been unable to improve their health, even after seeing numerous doctors, to be able to help them finally feel better. There’s also our store where there’s a number of products like our Elemental Heal line, our probiotic line, and other gut supportive and health-supportive supplements. We now offer health coaching. So if you’ve read the book or listened to a podcast like this one, or are reading about a product and you need some help with how or when to use, or how to integrate with diet, we now offer health coaching to help you along your way. And then finally, if you are a clinician, there is our clinicians’ newsletter, the Future of Functional Medicine Review. I’m very proud to say, we’ve now had doctors who’ve read that newsletter, find challenging cases in their practices, apply what we teach in the newsletter and be able to help these patients who were otherwise considered challenging cases. Everything for these resources can be accessed through drruscio.com/Resources. Alrighty, back to the show.

DrMR:

So that was an assortment of a few of the case study or research studies from the Future of Functional Medicine Review. I really hope that you will sign up during the month of April to obtain your first month of all access for a dollar.  Start reading through this to get a better sense of what the case studies look like. They are a combination of all the research and learning and reflection that we’re doing at the clinic. And also some of these important studies that are what underlies the evolving opinion that I and the clinical staff have on things like SIBO. Again, you’ve probably noticed over the past few years, my position on SIBO has become softer. And these last two research studies were part of that softening. In any case, there are some hopefully pearls from the Future of Functional Medicine Review. I do hope that you will join, read, learn, and join us in trying to take a great field and make it even better by excising some of the things that are a bit wasteful and really focusing on the things that work.

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