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Navigating irritable bowel syndrome: Causes, testing, and functional medicine treatment options

Updated: Dec 7, 2023

Irritable Bowel Syndrome (IBS) is a condition that affects millions of people worldwide, causing chronic abdominal pain and altered bowel habits. While it's a common disorder, many individuals have experienced the frustration of living with IBS without a proper diagnosis or understanding of the condition. In this interview Dr. Meeneghan shares his personal journey with IBS, shedding light on why treating this condition is personal for him, and then we delve into the diagnostic criteria, potential causes, and treatment options for IBS.

Dr. Meeneghan's Personal Experience

Dr. Meeheghan shares that he's had digestive issues since he was a child, and for the longest time, simply accepted it. It wasn't until he embarked on his medical school journey that he learned about his condition, its official name, IBS, and that there were steps he could take to manage it better. This revelation made him passionate about helping others with IBS because he understands firsthand the challenges and uncertainties that come with this condition.

Understanding IBS and IBS-D

How Common is IBS?

IBS is incredibly common, affecting approximately 1 in 10 people. Some studies even suggest that as many as 1 in 5 individuals may experience IBS at some point in their lives. However, Dr. Meeneghan reports he was part of the 40% of people with IBS who went undiagnosed for a significant period.

Diagnosing IBS-D: The Rome IV Criteria

Doctors use a set of criteria known as the Rome IV criteria to diagnose IBS-D. These criteria include recurrent abdominal pain occurring on average at least once a week for the past three months, associated with specific factors such as changes in stool frequency and appearance.

It's essential to note that there isn't a specific test that can definitively confirm IBS, so diagnosis often relies on the exclusion of other conditions through various tests and assessments.

What's Not Common in IBS?

While IBS-D can present with various symptoms, certain signs are NOT typically associated with this condition. These include large-volume diarrhea, bloody stools, nocturnal diarrhea, and greasy stools. Alarm features like these may indicate a different underlying condition, prompting further investigation.

Diagnostic Tests for IBS-D

Doctors may perform a range of tests, as there is no single test that tells you you have IBS. However, it is important to rule out other potential causes of digestive symptoms before diagnosing IBS. These tests might include a complete blood count to check for anemia, stool tests to screen for infections like giardia, and blood and stool tests to assess inflammation markers or abnormalities in thyroid hormones. An upper and lower endoscopy can also be used to rule in or rule out inflammatory bowel disease (IBD), although it's not always necessary for an IBS-D diagnosis.

This model of IBS shows how IBS is influenced by biological, psychological, and social factors. Early life experiences, psychosocial trauma, and maladaptive coping mechanisms can influence the severity of IBS symptoms. Assessments like the Adverse Childhood Experiences questionnaire look at childhood trauma exposure and can help uncover relevant factors. The treatment of IBS typically needs to address all three factors: biological, psychological and social.

Exploring the Potential Factors that contribute to IBS-D symptoms

The causes of IBS-D can be complex and multifaceted. Various factors may contribute to the development of this condition, including:

Visceral Hypersensitivity: Increased sensitivity to stimuli can result in heightened sensations and discomfort in response to normal gut activities and normal distension. This is an important area to target in the treatment of IBS.

Intestinal Inflammation: White blood cells and mast cells can release mediators that stimulate abnormal intestinal responses and motility may be a factor in IBS.

Post-infectious IBS: Acute gastrointestinal infections can increase the likelihood of developing IBS-D, with various risk factors influencing this outcome.

Alteration in Microbiota: The gut microbiome may play a role in IBS-D, with studies highlighting differences between individuals with IBS-D and those without the condition. Probiotics may offer benefits for some, but not all. There still needs to be more research done on how the microbiome may influence IBS.

Bacterial Overgrowth: Overgrowth of certain microorganisms, including bacteria and yeast, may also contribute to IBS-D symptoms. At modrn med we use a lactulose breath test to evaluate for bacterial overgrowth (SIBO) and intestinal methanogen overgrowth (IMO).

Food Sensitivities: Sensitivity to specific foods, such as foods high in fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAPs) may worsen symptoms of IBS in some people.

Genetics: There is evidence to suggest that genetics may play a role in IBS, but the relationship is complex and not fully understood. One study found that having a parent with IBS was a greater independent predictor of IBS than having an affected twin, suggesting that the familial nature of IBS could be due to social learning, as well as genetics.

Treatment Options for IBS-D

Effective treatment for IBS-D starts with a precise diagnosis. Conventional treatment options include dietary modifications, medications, and lifestyle changes. Some common approaches include:

Dietary Modification: Eliminating gas-producing foods, following a low-FODMAP diet, lactose avoidance can provide relief for many.

Medications: Antidiarrheal drugs, bile acid sequestrates, antispasmodics, antidepressants, antibiotics, mast cell stabilizers, and simethicone are among some of the medications used to treat IBS-D.

Gut-brain axis: There's a significant component of the gut-brain axis involved in IBS, particularly concerning visceral hypersensitivity. This heightened sensitivity to pressure changes can lead to increased pain perception, which is a key diagnostic criterion for IBS.

Testing: Specialized tests, such as the lactulose breath test, anti-vinculin and anti-CdtB antibody testing can provide valuable insights into the underlying causes of IBS-D. In addition to these, we also do a comprehensive blood panel to rule out other factors that could be contributing to symptoms, some of these blood tests include thyroid markers and inflammatory markers, sucrose breath test, H. pylori test, pancreatic markers and PCR stool test for infectious organisms. Testing is always individualized to the person based on their specific presentation.

Gluten sensitivity: A study in patients with irritable bowel syndrome with diarrhea who did not have celiac disease found that dietary gluten altered small intestinal permeability and had a greater effect on bowel movement frequency in patients who were HLA-DQ2/8 positive compared with those who were HLA-DQ2/8 negative.

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The information in this blog is not intended or implied to be a substitute for professional medical advice, diagnosis or treatment. All content, including text, graphics, images and information, contained on or available through this blog is for general information purposes only. Modrn med and Dr. Mary Pardee make no representation and assume no responsibility for the accuracy of information contained in or made available through this blog, and such information is subject to change without notice. This blog does not provide medical services, diagnosis or counsel. You are encouraged to confirm any information obtained from or through this email with other sources, and review all information regarding any medical condition or treatment with your physician. Never disregard professional medical advice or delay seeking medical treatment because of something you have read on or accessed through this information.

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