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Small Intestinal Bacterial Overgrowth and Irritable Bowel Syndrome

Testing and Treatment Options

I’ve spent past blogs talking in detail about digestion 101, IBS, leaky gut, etc.. This month will be much less about each of these and direct info about testing for both IBS and all different types of SIBO, which you’ll learn are quite interrelated.

IBS is a chronic digestive disorder that often is not connected to any other cause and becomes the diagnosis of exclusion of things like Celiac, Crohn’s, Colitis, and food sensitivities. IBS is no more than a collection of symptoms without a specific cause, which can be incredibly frustrating from a treatment perspective. IBS is typically a disorder in the large intestine-but as you read further I’ll share how often the origin of it may be something else. IBS is often a motility disorder that includes increased sensitivity to pain as well among other symptoms.

The first test for IBS is now available directly to patients! Let me explain a bit… IBS - SMART measures the levels of two biomarkers: anti-CdtB and anti-vinculin. One or both of these are elevated in those patients with diarrhea or mixed diarrhea and constipation. These markers are not elevated in those with IBS-C. If you go to you can fill out a symptom profile and order a test and get actionable results emailed to you and do a post-test consult with a doctor online. Food poisoning is found to be the leading cause of IBS-M and IBS-D. If you have either of these conditions, either diagnosed officially or not and also have abdominal pain and bloating this may be a good first step for you. If your test comes back positive, treatments to target your gut microbiome can be used. Your doctor can also order IBS-SMART online for you. If you’re a research buff you can view the article online on this HERE “The microbiome and its role in IBS”. You can then work with a doctor or Functional Health provider to assist in managing your care.

SIBO (Small Intestinal Bacterial Overgrowth) is the cause of IBS over 70 percent of the time. SIBO is defined by the overgrowth bacteria in the small intestine. The normal balance in the gut is significantly disrupted with SIBO. SIBO can be a result of other diseases, or large doses of antibiotics. The symptoms of SIBO arise from the malabsorption of nutrients, alteration in intestinal permeability, inflammation, and or immune activation that arises from the abnormal bacterial fermentation in the small bowel. SIBO is an actual diagnosis that has treatment options, thus you likely don’t have “IBS” you have SIBO…. The TRIO-SMART triple breath test is great for patients who experience bloating, gas, abdominal pain and fast or slow motility. TRIOSMART measures the level of certain gases in your breath: hydrogen, methane, and hydrogen sulfide. Elevated gases of any of these indicate SIBO, or IMO, or excess hydrogen sulfide. Data from the test can help you take steps towards treatment and feeling better. Like IBS-SMART, you’ll complete a symptom checklist, and order a test kit to be shipped to your home. You’ll collect breath samples and send the test kit away to be analyzed and receive your results via email. There are 9 breath samples over about a 2-hour period (one every 15 min) You’ll get a bill that is itemized to send to insurance if you like as well. I have the CPT code if you like. Both of these tests are very new and advanced and its something to celebrate! The level of these tests will not be avail in your GI or GP office likely at this time.

Let’s break down the 3 gasses a bit more…

Hydrogen is produced when bacteria consume sugars. Hydrogen levels are considered abnormal when the rise is greater than 20 ppm (parts per million) from the baseline within 90 minutes.

Methane is produced when archaea consume hydrogen. Methane levels are considered abnormal if they reach above 10ppm at any point during the breath test. IMO or Intestinal methanogenic overgrowth is an overgrowth of methane producing archaea in the small and large intestine. Elevated methane levels are associated with constipation and the level of methane ppm is associated with the degree of constipation.

Hydrogen sulfide is produced when sulfate reducing organisms consume hydrogen. Hydrogen sulfide levels are considered abnormal if they reach over 3ppm at any point during the test. Excess hydrogen sulfide is associated with diarrhea and the level of hydrogen sulfide is associated with the degree of diarrhea.

All the gasses interact with each other. For example, hydrogen is produced by fermented bacteria but also consumed by other organisms, resulting in the production of other gasses.

The first breath sample is a baseline. The remainders measure a rise in gasses after swallowing either lactulose (suggested but you need a script) or a glucose substrate. You may get bloated to not feel good after swallowing this substrate. It should be better within 24 hours. A step by step instructional video is online at TRIOSMART is the ONLY breath test available that can measure all 3 fermented gasses in your microbiome. The results can lead to a personalized tx plan more quickly. The third test I really like to get a full picture of your large intestinal make-up is the GI-MAP. HERE is a link that explains this test. Contact me if you are interested in this test, it can be ordered by a professional locally.

SIBO and IBS are very connected. Using the breath test for SIBO and the antibody test for IBS are both important to diagnose and treat GI symptoms. The IBS test can clinically rule out post infectious IBS, or IBS caused by food poisoning. I hope this helps all of you get answers quickly! Contact me anytime with questions or after your test results!

Keep Moving Forward 😊 Sarah

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