FMT for Patients With IBS With Fecal and Mucosal Microbiota Assessment

Irritable bowel syndrome (IBS) is a common functional bowel disorder of the gastrointestinal tract affecting up to 20 percent of the adolescent and adult populations. It is characterised by abdominal pain, irregular bowel habits, altered stool consistencies and bloating, and is associated with impaired quality of life. IBS can be categorised into diarrhoea predominant type (IBS-D), constipation predominant type (IBS-C), and mixed type (IBS-M). Until recently, the development of an effective therapy for this condition has been hampered by a poor understanding of the etiology of the disease. Traditionally the underlying pathogenesis of IBS has been centered on the brain-gut axis whereby stress and psychological conditions alter the perception of IBS symptoms. Emerging evidence however supports the observation that at least in a subgroup of patients with IBS, peripheral mechanisms within the intestine including low grade mucosal inflammation, abnormal immune activation and altered visceral sensitivity may be the main drivers of the manifestations in IBS.

Accumulating data suggest that the intestinal microbiota play an important role in the pathophysiology of IBS. This is derived from early observation that post-infectious IBS developed in a subgroup of patients following a bout of gastroenteritis. Several studies have shown that the fecal microbiota was altered in IBS and IBS symptoms can be improved by therapeutic interventions that target the microbiota including antibiotics, probiotics and prebiotics. Rifaximin, an oral, non-systemic broad spectrum antibiotics has also been shown to provide significant relief in IBS symptoms in a randomized controlled trial.

Fecal microbiota transplantation (FMT) defined as infusion of feces from healthy donors to affected subjects has shown impressive results with high cure rates in patients with recurrent clostridium difficile infections.The mechanism of FMT in IBS is not completely clear.

The investigators propose a randomised, placebo-controlled trial of FMT in patients with IBS.

Inclusion criteria

• Patients are aged 18 or above
• Patients have a diagnosis of IBS consistent with the Rome III criteria (13)
• Patients did not have adequate relief of global IBS symptoms and of IBS-related bloating at both the time of screening and the time of randomization
• Patients had undergone clinical investigations with colonoscopy within five years of recruitment
• Patients with written informed consent form provided

Exclusion criteria

• Patients have constipation predominant IBS (according to the definition of Rome III criteria)
• Patients have a history of inflammatory bowel disease or gastrointestinal malignancy
• Patients have previous abdominal surgery (other than cholecystectomy or appendectomy)
• Patients have human immunodeficiency virus infection
• Patients have renal disease manifested by 1.5 times the ULN of serum creatinine or blood urea nitrogen level
• Patients have hepatic disease manifested by twice the upper limit of normal (ULN) for any of the following liver function tests: alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, or total bilirubin (except in isolated elevation of unconjugated bilirubin
• Patients have diabetes mellitus manifested by HbA1C > 6.5%
• Patients have abnormal thyroid function manifested by values of serum Sensitive Thyroid Stimulating Hormone and serum free T4 fall outside the reference range which is not controlled by thyroid medications
• Patients have a history of psychiatric illness (mania and schizophrenia)
• Patients have depression defined by having a Patient Health Questionnaire-9 (PHQ-9) score > 15
• Patients have anxiety defined by having a Generalized Anxiety Disorder 7 (GAD7) score > 10
• Patients have active infection at the time of inclusion
• Patients have used antibiotic therapy or anti-inflammatory drugs within the past 7 days
• Patients have any other organic causes that can explain the symptoms of IBS
• Current pregnancy