Irritable Bowel Syndrome, also known as IBS, is the most commonly diagnosed digestive disorder. While the cause of IBS is unknown, physicians are able to make a diagnosis based on the symptoms alone. IBS can be split into four categories based on which symptoms patients have, and each has its own treatment plan.
Roughly 70-80% of all patients diagnosed with IBS have SIBO/IMO, or Small Intestinal Bacterial Overgrowth/Intestinal Methogen Overgrowth. A Hydrogen and Methane breath test can test for this.
Who Can Have IBS
IBS is a common condition, with very few patients developing severe symptoms. While anyone can develop this disorder, younger people are more likely to develop it. Women are also twice as likely to develop IBS than men.
What IBS Does
Individuals with IBS can experience abdominal pain as well as altered bowel habits. The cause of this condition is largely unknown, so chronic cases are common.
Symptoms of IBS
Symptoms include diarrhea, abdominal pain, belching, constipation, bloating, gas, and anxiety. Due to the nature of the disease, there may be times where symptoms worsen and others where they disappear.
Our body utilizes muscle contractions to push substances through the digestive tract. IBS can alter these normally regulated contractions. If these muscle contractions are weakened, it can lead to constipation as the substances are unable to move. And if these contractions are strengthened or occur more frequently, it can lead to diarrhea, gas, and bloating.
Diagnosis
IBS is a syndrome diagnosis, usually made by a total investigation of symptoms. As such, a physician should rule out other conditions before giving a diagnosis of IBS. A combination of laboratory and other tests are the best way to rule out another digestive diagnosis that could be causing IBS symptoms. It is also possible to break down the diagnosis into one of four subcategories. If the patient has constipation, they can be diagnosed with IBS-C. If the patient has diarrhea, they can be diagnosed with IBS-D. And if the patient has a mixture of both, they can be diagnosed with IBS-M. The fourth category is IBS-U, or unknown.
The IBS Smart test is a blood test that can determine the cause of IBS-D or IBS-M. Gastroenterologists designed this test to check for two antibodies, Anti-CdtB and Anti-Vinculin. These two antibodies can be found in patients who have a history of gastroenteritis, or food poisoning. Anti-Cytolethal Distending Toxin B, or Anti-CdtB, is a toxin from bacteria infections that can trigger an immune response from the body. This immune response fights back against the toxin, triggering Anti-Vinculin antibodies. When the infection is over, the remaining antibodies can damage certain cells, called Interstitial cells, inside the intestinal tract. This can cause bloating, diarrhea, and abdominal pain. This can also cause damage to the cells lining the intestinal tract, causing malabsorption or leaky gut.
E. coli, C. jejuni, Shigella, and Salmonella infections are usually responsible for creating Anti-CdtB.
Research studies have shown that 1 in 9 people who have a history of food poisoning develop IBS and that up to 60% of cases of IBS-D are post-infectious in nature.
Rome Criteria
Physicians also use a process known as the Rome criteria to help make a diagnosis. This is an internationally recognized symptom checklist that is updated to have the most accurate information possible.
In order to diagnose IBS in accordance with Rome IV criteria, a patient needs to meet the following criteria:
| Recurrent abdominal pain on average at least 1 day/week in the last 3 months, associated with two or more of the following criteria: |
|---|
| 1. Related to defecation |
| 2. Associated with a change in the frequency of stool |
| 3. Associated with a change in the form (appearance) of stool |
These criteria should be fulfilled for the past three months, with symptom onset at least 6 months prior to diagnosis (6).
DDX
To first make a diagnosis, certain other diseases must be ruled out, as this is a diagnosis of exclusion. Doctors must first rule out Ulcerative Colitis, Crohn’s Disease, lactose intolerance, bowel obstruction, malabsorption, and cancer, among others. Doctors do not usually rule out SIBO and IMO Due to a current lack of knowledge in the mainstream medical community.
Allopathic Treatment
Allopathic treatment changes depending on the symptoms. Physicians typically recommend a course of antibiotics for individuals with diarrhea. For those with constipation, a laxative (Linaclotide) or a Cl channel blocker called Lubiprostone is used. Muscle relaxants (Dicyclomine) may help reduce any abdominal pain, along with anti-spasmodic Dicycloverine or the anticholinergic Hyoscyamine. Patients who aggravate their symptoms with stress may be given anti-depressants (amitriptyline, imipramine) of the TCA class. Symptomatic relief of nausea can also be given (Ondansetron). For Patients suffering from IBS-D, diphenoxylate or loperamide can provide relief.
Naturopathic Treatment
PNM’s goal is to flush out the bad bacteria and repair the digestive tract. We can achieve this through the use of probiotics such as L. rhamnosus GG, LC705, B. infantis 35624, B. animalis, etc (5). We can also use dietary modifications, and supplements tailored to your body and needs.
PNM uses the Hydrogen and Methane breath test and lab work to determine the source of these symptoms. We must first rule out SIBO, IMO, leaky gut, and malabsorption before diagnosing IBS. The breath test looks for bacteria in the digestive tract, which may be responsible for causing the symptoms.
By changing the bacteria that live in the gut microbiome, we are able to reduce the levels of bad bacteria and replace them with good bacteria. This will not only ease symptoms and reduce inflammation but help repair the gut. There are also supplements that can help restore the digestive lining, returning your digestive tract back to normal.
Ultimately, it will be the combination of different symptoms that will determine the treatment plan. Because every case can be different, they need their own personalized, tailored plan. Common supplements used include L-tryptophan, 5-HTP, Peppermint oil, probiotics, glutamine, Low FODMAP Diets, and high fiber. Lifestyle changes may include stress reduction, exercise, long-term personal dietary advice, and more.
Potential Complications of IBS
There are minimal complications for people who suffer from IBS. There doesn’t appear to be an increased risk of inflammatory bowel diseases or colorectal cancer in people with IBS.
Related Bacteria
Research has linked the Alistipes spp. bacteria to IBS. Patients affected by depression disorder showed overexpression of Alistipes. This bacteria, a genus in the Bacteroidetes phylum, have shown overexpression in other disorders as well. Patients with chronic fatigue syndrome and IBS also show overexpression of Alistipes. This bacteria can generate inflammatory molecules that are able to spread into the bloodstream when the intestinal wall has been weakened by inflammation. Just as these molecules can inflame the intestine wall, creating IBS, once they reach the bloodstream they can spread inflammation.
Another study, carried on by Jiang et al, confirmed the overexpression of Alistipes in psychiatric disorders and observed a negative correlation between the expression of Faecalibacterium and the severity of depressive manifestations. [PMC 4698498]
The Bacteroidetes and Faecalbacterium bacteria strains are among many covered in Dr. Brody’s microbiome analysis.
Related Genes
TPH2 is a gene that creates a precursor to serotonin. This precursor can cause the muscles in the digestive tract to relax. According to this PubMed article, serotonin is localized in some of the cells within the digestive tract and the nervous system. It can be released into the blood, or into the gut. As such, serotonin – and therefore TPH2 – can affect our digestion and digestive tract in multiple ways. HTR2A is a serotonin receptor gene and is another key gene to look at for its effects on serotonin.
The gene NR3C1 is where cortisol and other stress hormones bind. This gene is present in almost every cell in the body. Therefore, any mutations can cause inflammation and imbalance with other genes and cytokines, and little proteins are created to communicate and interact in certain ways between cells.
Any mutations to the CACNA1B gene can cause higher susceptibility to pain and inflammation in the body, including the digestive tract.
Women who have the SLC6A4 gene are more likely to experience IBS-D, according to this PubMed article. This gene plays a key role in internal peristalsis, the involuntary muscle contractions that move food throughout the digestive system. NXPH1 can also increase the risk of IBS-D in both genders, according to this PubMed article.
For more information on genes, there is an article on PubMed article which can be read here.
References
(1) Irritable bowel syndrome. (2018, March 17). Retrieved May 18, 2020, from https://www.mayoclinic.org/diseases-conditions/irritable-bowel-syndrome/symptoms-causes/syc-20360016
(2) Prevalence, Risk Factors, and Outcomes Of Irritable Bowel Syndrome After Infectious Enteritis: A Systematic Review and Meta-analysis Klem F;Wadhwa A;Prokop LJ;Sundt WJ;Farrugia G;Camilleri M;Singh S;Grover M; – https://pubmed.ncbi.nlm.nih.gov/28069350/
(3) Development and Validation Of a Biomarker For Diarrhea-predominant Irritable Bowel Syndrome in Human Subjects Pimentel M;Morales W;Rezaie A;Marsh E;Lembo A;Mirocha J;Leffler DA;Marsh Z;Weitsman S;Chua KS;Barlow GM;Bortey E;Forbes W;Yu A;Chang C; – https://pubmed.ncbi.nlm.nih.gov/25970536/
(4) Altered Fecal Microbiota Composition in Patients With Major Depressive Disorder Jiang H;Ling Z;Zhang Y;Mao H;Ma Z;Yin Y;Wang W;Tang W;Tan Z;Shi J;Li L;Ruan B; – https://pubmed.ncbi.nlm.nih.gov/25882912/
(5) Yarnell, E. (2011). Natural Approach to Gastroenterology (Second, Vol. 1). Seattle: Healing Mountain Pub.
(6) Rome Criteria and a Diagnostic Approach To Irritable Bowel Syndrome Brian Lacy-Nihal Patel; – https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5704116/
(7) Action Of Serotonin on the Gastrointestinal Tract Ormsbee JD; – https://pubmed.ncbi.nlm.nih.gov/3919396/
(8) Association Between a Functional Polymorphism in the Serotonin Transporter Gene and Diarrhoea Predominant Irritable Bowel Syndrome in Women Yeo A;Boyd P;Lumsden S;Saunders T;Handley A;Stubbins M;Knaggs A;Asquith S;Taylor I;Bahari B;Crocker N;Rallan R;Varsani S;Montgomery D;Alpers DH;Dukes GE;Purvis I;Hicks GA; – https://pubmed.ncbi.nlm.nih.gov/15361494/
(9) Genetic Variants in CDC42 and NXPH1 As Susceptibility Factors For Constipation and Diarrhoea Predominant Irritable Bowel Syndrome Wouters MM;Lambrechts D;Knapp M;Cleynen I;Whorwell P;Agréus L;Dlugosz A;Schmidt PT;Halfvarson J;Simrén M;Ohlsson B;Karling P;Van Wanrooy S;Mondelaers S;Vermeire S;Lindberg G;Spiller R;Dukes G;D’Amato M;Boeckxstaens G; – https://pubmed.ncbi.nlm.nih.gov/24041540/
(10) The Role Of Genetics in IBS. Yuri Saito – https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3056499/