Personalized Probiotic Treatments for Irritable Bowel Syndrome

Irritable bowel syndrome (IBS) is characterized by stomach pain and altered bowel habits. It affects about 5 million people in Canada. Doctors don't fully understand what causes IBS, so treatments often don't work well. Many patients say certain foods make their symptoms worse. This may be due to how gut bacteria break down food. Some bacteria produce harmful chemicals like histamine and lysophosphatidylcholine (LPC)/lysophosphatidic acid (LPA), which can cause pain and gut problems. These chemicals may affect about 35% of IBS patients. The goal is to find out which patients have these bacteria. Then, doctors can give them treatments that match their gut bacteria. This could help reduce symptoms and improve their lives. If the study is successful, it could change how we understand, diagnose, and treat IBS, leading to new treatments that focus on personalized microbiota-directed treatments targeting specific causative mechanisms.

Inclusion Criteria: * Diagnosis of Irritable Bowel Syndrome * Willing and able to sign written informed consent * At least moderate IBS symptoms (IBS-SSS \>175) Exclusion Criteria: * Use of antibiotics, antibiotics or probiotics, currently or within the last 4 weeks * New IBS treatments (mediations, diet or psychotherapy) started within last 3 months. Medications will be allowed, provided the patient is on a stable dose for more than 3 months. * Current organic gastrointestinal or autoimmune diseases, such as type 1 diabetes, celiac disease or inflammatory bowel disease * History of major gastrointestinal surgery (bariatric surgery, gastrectomy, colectomy, bowel resection) * Connective tissue disease * Alcohol or drug abuse * Concurrent systemic disease and/or laboratory abnormalities considered by investigators to be a risk or that could interfere with data collection Participation in another dietary or pharmacological treatment study within the last 4 weeks