Diagnose IBS and target gut microbiota and metabolites to improve symptoms

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The educational content in this post was created in collaboration with Bromatech and independently developed and approved by the GMFH publishing team and editorial board.

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Diagnosed with IBS

The use of symptom-based criteria for the diagnosis of gastrointestinal dysfunction may help physicians diagnose and justify such disorders, rather than seeing them solely as a combination of symptoms. A major improvement towards the understanding of these disorders was introduced by the Rome Foundation standards. A number of standards have been adopted, the last being related to the Rome IV standards (2016). Rome IV changed the term from functional disorder to disordered gut-brain interaction (DGBI) because the term “functional” implied illegality and stigmatized patients.¹.

Even if the diagnosis is made according to the above criteria, Specific tests can rule out inflammatory bowel disease and celiac disease, as well as bile acid diarrhea, congenital sucrose isomaltase deficiency, histamine-mediated diseases, systemic nickel allergy, and high fecal burden associated with pelvic floor dysfunction. It may be helpful to do so.³. It has also been reported that post-infectious irritable bowel syndrome may occur in approximately 11% of people suffering from acute infections.^Four. Recent studies have also shown that COVID-19 infection may increase the risk of developing chronic bowel symptoms and irritable bowel syndrome.^5,6.

Many patients diagnosed with IBS may also seek further diagnosis. However, if the doctor can identify the patient’s complaints as factual and make a diagnosis based on these criteria, Patients are more likely to accept the diagnosis if you engage them in a patient-centered dialogue by providing empathy, explaining disease mechanisms, and finding possible solutions to improve their physiological condition. Masu..

The easier it is to understand the disease, the more appropriate the treatment will be! The good news is that a positive diagnosis of IBS using symptom-based criteria and limited investigation is durable and safe, highlighting that IBS is not associated with the development of organic gastrointestinal disease. Masu.².

IBS subtypes and overlapping symptoms impact clinical management

IBS is divided into four subtypes based on your primary bowel habits.

• IBS with frequent constipation
• IBS with major diarrhea
• IBS with mixed bowel habits
• IBS unclassified

Additionally, if these symptoms are not accompanied by pain, you may have functional diarrhea or constipation. Functional bloating and bloating are only diagnosed if these are the main symptoms, and neither is necessary for his diagnosis of IBS.

To meet the Rome IV diagnostic criteria for IBS, the following symptoms must be present: abdomen I have had pain on average at least 1 day a week for the past 3 months (if the first onset was at least 6 months before diagnosis), With two of the following symptoms: pain related to defecation, a change in the frequency of defecation, or a change in the shape (appearance) of the stool.¹.

Targeting the gut microbiome to improve IBS symptoms

Although the pathogenesis of IBS is still partially unknown, an understanding of potential mechanisms including the gut microbiome, gut-brain axis, changes in intestinal motility, epithelial barrier, immune system, enteric nervous system, and specific diseases continues to improve. It has progressed rapidly over the years.Food antigens, psychological and genetic factors⁷.

Post-infectious IBS model shows that changes in gut microbiota play a central role as a key mechanism of IBS. Other clinical scenarios linking IBS and gut microbiota include increased risk of IBS induced by systemic administration of antibiotics and improvement of IBS symptoms after ingestion of probiotics or non-absorbable antibiotics. will appear.

Microbiome dysbiosis in IBS has been recognized by the Rome Foundation as a factor that may contribute to this disorder⁸. Experiments using animal models aimed at demonstrating the importance and possible etiological role of the microbiota in IBS have shown that when the microbiota of IBS patients colonizes germ-free animals, it induces visceral hypersensitivity and induces intestinal hypersensitivity. There is evidence that permeability may be impaired and gastrointestinal transit times altered.⁹.

specific bacteria (example: Bifidobacterium and Faecalibacterium genus and increase Lactobacillus family family, Bacteroides genus and Enterobacteriaceae family) Associated with the gut microbiome of IBS patientsHowever, it is too early to determine whether these microorganisms are the product or cause of IBS.^Ten. The severity of IBS symptoms may be associated with specific characteristics of the composition of the gut microbiota (i.e., low microbial richness; Bacteroides This highlights the potential of modulating the gut microbiota as a means to improve IBS symptoms and quality of life in these patients.

Involvement of the gut microenvironment in IBS symptoms suggests that antibiotics, prebiotics, and prebiotics exert therapeutic activity through their effects on gut microbiota composition, the level of microbial metabolites (e.g., short-chain gut microbiota). This has led to the publication of a series of studies suggesting the potential of chain fatty acids) and intestinal barrier integrity. However, the use of these gut microbiome-based therapies has not always been widely approved. This is the case of rifaximin as a non-absorbable antibiotic in IBS, and its use is based on its potential ability to alter the altered intestinal flora, but regarding the therapeutic role of antibiotics in IBS. More clinical research is needed to better establish an understanding of the¹¹.

Future microbiome therapeutics in the pipeline for IBS include fecal microbiota transplants, microbial consortia, phages, and engineered bacteria, but these strategies may translate their physiological effects into potential clinical practice. I’m still researching to do that. For example, Quigley and colleagues recently discovered the next generation of probiotics. Blautia hydronotropica (MRx1234) is a new potentially safe treatment option for patients with IBS constipation, IBD-D, or mixed symptoms¹².

Recent studies also support other novel targets of potential interest for managing IBS symptoms. Histamine produced by certain intestinal bacteria is involved in abdominal pain, suggesting a role for targeting bacterial histamine in the management of abdominal pain in IBS. Continuation of a low FODMAP diet was also superior to the antispasmodic drug otilonium bromide in improving symptoms in primary care patients with IBS. Sequestration of harmful molecules in the intestinal environment via intestinal adsorbents holds promise for improving stool consistency, abdominal pain, stool frequency, and sense of urgency in patients with IBD-predominant diarrhea It has also been shown that Overall, these findings suggest the possibility of influencing the gut microbiota and metabolites as a means to improve IBS symptoms.¹³.

take home message

• Symptom-based criteria for IBS allow doctors to make a diagnosis with limited investigation.
• Certain tests may be helpful to help rule out less common organic diseases.
• IBS can develop slowly or rapidly in association with an infection (post-infectious IBS).
• Changes in the composition and function of the gut microbiota are thought to be involved in the onset and development of IBS, and specific gut microbiota profiles are associated with the severity of IBS symptoms.
• Future microbiome treatments in the pipeline for IBS include fecal microbiota transplants, microbial consortia, phages, and engineered bacteria, but are not yet ready for use in clinical settings.

References:

1. Drosman DA. Functional gastrointestinal disorders: history, pathophysiology, clinical features, and Rome IV. Department of Gastroenterology. 2016 2 19:S0016-5085(16)00223-7. doi:10.1053/j.gastro.2016.02.032. Epub ahead of print.
2. Casone M, Craig OF, Gracie DJ, et al. Diagnosis of irritable bowel syndrome using Rome IV criteria and limited research is valid even in second-line treatment. Clin Gastroenterol Hepatol. 2023 6 9:S1542-3565(23)00444-5. doi:10.1016/j.cgh.2023.05.022. Online ahead of print.
3. Camilleri M, Boexterns G. Irritable Bowel Syndrome: Pathophysiology and Biomarker-Based Treatment. intestines. 2023 Mar;72(3):590-599. doi:10.1136/gutjnl-2022-328515.
4. Barbara G, Grover M, Bercik P, et al. Rome Foundation Working Team Report on Post-Infectious Irritable Bowel Syndrome. Department of Gastroenterology. 2019 January;156(1):46-58.e7. doi: 10.1053/j.gastro.2018.07.011.
5. Marasco G, Clement C, Barbaro MR, et al. GI-COVID19 Research Group. Irritable bowel syndrome after the new coronavirus infection. intestines. 2022 12 9:gutjnl-2022-328483. doi:10.1136/gutjnl-2022-328483. Epub ahead of print.
6. Noviello D, Costantino A, Muscatello A, et al. Functional gastrointestinal and somatoform symptoms 5 months after SARS-CoV-2 infection: a controlled cohort study. neurogastrointestinal rollmotil. 2022 Feb;34(2):e14187. doi: 10.1111/nmo.14187.
7. Chey WD, Kurlander J, Eswaran S. Irritable bowel syndrome: a clinical review. Japan Automobile Manufacturers Association. 2015 March 3;313(9):949-58. doi: 10.1001/jama.2015.0954.
8. Simren M, Barbara G, Flint HJ, et al. Rome Foundation Committee. Gut microbiota in functional bowel diseases: a Rome Foundation report. intestines. 2013 Jan;62(1):159-76. doi:10.1136/gutjnl-2012-302167.
9. Kruse L, Gaultier E, Delhomme C, Cartier C, Delmas E, Dapoigny M, Fioramonti J, Bernalier-Donadille A. Hypersensitivity to colonic distension in IBS patients may also be transferred to rats via the fecal microbiota. neurogastrointestinal rollmotil. 2013 Apr;25(4):e272-82. doi: 10.1111/nmo.12103.
10. Pittayanon R, Lau JT, Yuan Y, et al. Intestinal microbiota of patients with irritable bowel syndrome – a systematic review. Department of Gastroenterology. 2019 Jul;157(1):97-108. doi: 10.1053/j.gastro.2019.03.049.
11. Iribarren C, Maasfe L, Ohman L, et al. Modulation of the intestinal microenvironment as a therapeutic strategy for irritable bowel syndrome: a narrative review. intestinal microbiota. 2022;3:e7. doi:10.1017/gmb.2022.6.
12. Quigley EMM, Markinson L, Stevenson A, et al. Randomized Clinical Trial: Efficacy and Safety of Live Biotherapy Product MRx1234 in Irritable Bowel Syndrome Patients. nutritional pharmacotherapy. 2023; 57(1):81-93. doi: 10.1111/apt.17310.
13. Simren M. Targeting the intestinal microenvironment of IBS to improve symptoms. Nat Rev Gastrointestinal Roll Hepatol. 2023; 20(2):69-70. doi: 10.1038/s41575-022-00718-3.