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Top Labs To Run Bi-Annually On Your SIBO Patients

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Top Labs To Run Bi-Annually On Your SIBO Patients

SIBO (small intestinal bacterial overgrowth) is a digestive issue that is commonly overlooked or misdiagnosed because of its similarities to IBS (Irritable Bowel Syndrome). In fact, up to 80% of IBS patients have SIBO suggesting that SIBO may be a primary cause for a proportion of these patients.

This insight provides a positive outlook as it offers ways to address digestive issues that were once thought to be psychogenic in cause, such as in the case of IBS. Regular testing can be valuable in investigating underlying causes such as SIBO for these previously unexplained digestive issues. These tests can highlight organic reasons that may be contributing to the symptoms enabling more targeted treatment approaches to improve health outcomes.


What is SIBO?

SIBO refers to when there is an increase in bacterial overgrowth in the small intestine. The small intestine usually has a relatively small amount of bacteria. The issue arises when there is an over-accumulation of bacteria in this area. The overgrowth of bacteria will ferment consumed carbohydrates, which produces excess gas and causes symptoms.

SIBO can be classified into three distinct subtypes based on the gases produced by the bacteria in the intestines. The first subtype is Hydrogen (H2)-dominant SIBO, diagnosed by elevated hydrogen levels on the SIBO breath test. It is associated with an overgrowth of specific bacteria like Streptococcus, E. coli, and Staphylococcus and is commonly linked to IBS-diarrhea (IBS-D). The second subtype is Intestinal Methanogen Overgrowth (IMO), previously known as methane (CH4) dominant-SIBO, resulting from an overgrowth of methanogens, which are archaea, not bacteria. IMO is more strongly correlated with IBS-constipation (IBS-C). The third and most recently discovered subtype is Hydrogen Sulfide (H2S)-dominant SIBO, characterized by excessive bacterial production of H2S gas. This type is associated with diarrhea presentations and involves certain bacteria like Escherichia, Klebsiella, Proteus, and Desulfovibrio.

What Causes SIBO? 

SIBO can develop due to medications such as proton pump inhibitors, various medical conditions, and lifestyle habits. This digestive condition is primarily associated with diminished intestinal immunity, motility, and compartmentalization. One of the main factors contributing to SIBO is the deficiency of stomach acid, pancreatic enzymes, and bile, which allows bacteria to overgrow in the upper digestive tract. This deficiency can be caused by chronic stress, the use of acid-blocking medications, H. pylori infection, or gallbladder removal surgery. Additionally, impaired intestinal motility, specifically the diminished migrating motor complex (MMC), can hinder the proper movement of bacteria through the small intestine. Factors like frequent eating, stress, hypothyroidism, diabetes, and gastroparesis can negatively impact intestinal motility. Structural abnormalities in the intestines and abdomen, such as an incompetent ileocecal valve, abdominal surgeries leading to scar tissue, and fistulas, also contribute to SIBO development.

SIBO Symptoms

SIBO symptoms result from bacterial fermentation in the small intestine, intestinal immune activation, inflammation, increased intestinal permeability, and poor nutrient digestion and absorption.

Common SIBO symptoms include:

●  Abdominal pain

●  Gas

●  Flatulence

●  Bloating

●  Abdominal distension

●  Diarrhea

Other gastrointestinal symptoms may include:

●  Heartburn

●  Reflux

●  Nausea

●  Burping

●  Constipation

●  Fatty stools

●  Increasing food sensitivities

SIBO-related leaky gut can cause symptoms outside the digestive tract, such as:

●  Fatigue

●  Brain fog

●  Headaches

●  Mood changes

●  Skin issues

●  Joint pain

What Are The Benefits of Regular Lab Testing For Patients With SIBO?

Regular testing for SIBO is essential to monitor treatment progress and confirm eradication. After completing antimicrobial therapy, patients have the option to repeat the SIBO breath test. Unlike the initial test, they don't need to wait two weeks after finishing antibiotics. Promptly repeating the test provides accurate results on treatment effectiveness. Successful treatment is typically achieved when symptoms are improved by 80-90%. Regular testing utilizing the breath test and other functional tests ensures proper management and helps decide whether treatment should continue or stop.

Top Labs To Run Bi-Annually On Patients With SIBO

Before discussing the top labs to run for SIBO patients, it's important to note that the quantitative jejunal aspirate culture is seen as the most accurate way to diagnose SIBO. However, hydrogen breath tests have gained popularity due to their noninvasive nature, and there is no universal standard SIBO breath test. With that stated, here are the top functional labs that are typically run bi-annually for SIBO patients:

SIBO Breath Test

The SIBO breath test can be easily done at home by the patient following a one-day preparatory diet. It helps diagnose SIBO and its different subtypes by measuring bacterial fermentation gas products exhaled through the lungs. High levels of H2, CH4, and H2S in the breath indicate H2-dominant SIBO, Intestinal Methanogen Overgrowth (IMO), and H2S SIBO, respectively. This test measures all three gas types associated with SIBO. It should be utilized as a baseline before and after treatment to assess for eradication and if treatment should continue.

Comprehensive Stool Panel

This comprehensive stool test offers valuable information about SIBO by measuring fecal biomarkers. This test can identify potential contributors to SIBO development, such as digestive enzyme deficiencies, intestinal inflammation, and dysbiosis. Additionally, the tests can screen for consequences of SIBO, including malabsorption and intestinal permeability. The comprehensive stool panel results can guide specific treatment protocols to address underlying factors that can increase the risk of developing SIBO. It can also provide insights into the effectiveness of those treatment strategies so proper adjustments can be made.

Cortisol Stress Test

Salivary cortisol testing can detect disrupted stress responses by assessing cortisol secretion patterns. This functional test can identify chronic stress and cortisol imbalances that have a negative impact on gut function, which can contribute to the development of SIBO by assessing cortisol levels throughout the day. Healthcare providers can analyze test results to identify adrenal imbalances, which may result from excessive or insufficient cortisol levels. They can create personalized treatment plans by correlating the results with specific symptoms. Regular retesting allows for monitoring and adjustments to the treatment as necessary, and follow-up test reports help track progress over time.

Micronutrient Panel

SIBO can create long-lasting absorption issues. This condition can create nutrient deficiencies, worsen extraintestinal symptoms, and hinder gut healing. These issues can continue if the gut issues aren't fully addressed. Therefore, a thorough nutritional assessment that detects suboptimal and deficient levels of key micronutrients such as iron, vitamin D, and zinc may be necessary to run regularly to analyze these levels. The micronutrient panel is completed through a blood sample, and the results allow healthcare providers to make the adjustments needed for targeted dietary and supplement recommendations.

Thyroid Panel

Hypothyroidism negatively affects digestive enzyme secretions and intestinal motility, leading to ongoing inflammation in the intestines, which can trigger SIBO. Therefore, patients with hypothyroidism should have their thyroid levels checked regularly not only to manage their thyroid but also to reduce their risk of developing SIBO. Hypothyroidism can also worsen symptoms like fatigue and constipation. To assess thyroid function, a complete thyroid panel measures hormones and immune proteins involved in thyroid hormone production, screening for thyroid function via a blood sample.

Hemoglobin A1c (HbA1c)

Nerve damage from diabetes can affect the intestines, leading to gastroparesis (slowed stomach emptying), impaired intestinal motility, and can result in SIBO. Patients who are at risk for diabetes or who have diabetes should regularly check their HbA1c levels. This test which provides a three-month average of blood sugar levels, can help practitioners monitor diabetes risk and the effectiveness of treatment. Regular monitoring can guide practitioners on any adjustments needed for treatment, which can also reduce the risk of SIBO due to gastroparesis caused by diabetes.



SIBO is a prevalent digestive disorder that presents with IBS-like symptoms, making it sometimes missed in diagnosis. SIBO breath testing is a crucial tool for diagnosing gastrointestinal symptoms and identifying SIBO as a potential underlying cause of seemingly unrelated health conditions. Some conditions disrupt the body's natural defenses against bacterial overgrowth, contributing to SIBO development. On the other hand, SIBO can trigger imbalances that lead to extraintestinal symptoms and diseases. The relationship between SIBO and other health conditions emphasizes the importance of regular testing with multiple functional labs for a comprehensive analysis. The functional medicine approach uses comprehensive testing to uncover the root causes of illness. These test results can help tailor holistic treatment recommendations that address the underlying causes.

The information provided is not intended to be a substitute for professional medical advice. Always consult with your doctor or other qualified healthcare provider before taking any dietary supplement or making any changes to your diet or exercise routine.
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