Improvement in Food Intolerance Symptoms after Pretreatment with Antibiotics Followed by Faecal Microbiota Transplantation: A Case Report

Irritable bowel syndrome (IBS) is a chronic gastrointestinal condition characterized by abdominal pain and altered bowel habits. Non-immune food reactions or food intolerances affect up to 20% of the general population and are commonly seen in patients with IBS. Faecal microbiota transplantation (FMT) has been described as an emerging, effective treatment for IBS. To date, there have been no reports on changes in food intolerances in patients with IBS treated with FMT. A 35-year-old female presented with an 18-month history of nausea, abdominal pain, alternating bowel habits, headaches/migraines, brain fog, and fatigue. The patient described severe food intolerances to dairy, gluten, egg, and soy. Extensive investigation identified no pathology, and IBS was diagnosed. The patient underwent treatment with antibiotics followed by treatment with FMT enema infusions decreasing in frequency for 12 months. At 12-week follow-up during FMT infusions, the patient reported an 80–90% improvement in her symptoms with formed bowel motions 1–2/day, occasional abdominal pain, and nausea and improved energy levels. The patient reported progressive improvements in her food tolerance from approximately 2 months into the FMT treatment. At week 24, she was tolerating gluten and dairy foods in her diet. At week 52, she was including gluten and dairy in her diet with no symptoms. This case demonstrates that antibiotics, followed by FMT may be an effective treatment for IBS and food intolerances pointing to the gut microbiome as a potential target for treatment.