Irritable Bowel Syndrome and Functional Gastrointestinal Disorders

The most common cause of abdominal discomfort and change in bowel habit (diarrhoea or constipation) is functional gastrointestinal disorder (FGID) which encompasses irritable bowel syndrome (IBS), gastroesophageal reflux and constipation. This is a group of conditions where the way the intestines work is abnormal yet no structural abnormality is detected. It may be caused by abnormality in the hormones, nerves, intestinal bacteria or movement of the intestinal tract. While it generally does not result in death, the symptom may be very bothersome. There is no “cure” for this condition but the bothersome symptoms can usually be brought under control.

The doctor would assess the patient with interview and physical examination. The diagnosis of FGID can be made based on the presence of typical symptoms. In the case of IBS, the ROME III diagnostic criteria is used. It defines IBS by the presence of abdominal pain or discomfort for at least three days per month in the last three months associated with at least two of the following features:

• Improvement of abdominal pain after passing motion.
• Change in frequency of passing motion.
• Change in the form of the stool.

Investigations to exclude the presence of structural abnormality may be necessary especially in the presence of “alarm features” such as age more than 45 years old, difficulty in swallowing, blood in stool, unintended weight loss, pain while sleeping at night, fever, personal or family history of gastrointestinal cancer, abnormal physical examination and failure to improve with treatment. These investigations may include blood tests, abdominal scans and endoscopy (intestinal camera tests).

In some instances, further gastrointestinal function tests which assess the movement or the amount of bacteria in your intestines may be performed to establish the underlying cause and guide treatment but it is not necessary in most cases.

Irritable bowel syndrome and functional gastrointestinal disorders are longstanding conditions. The symptoms may come and go and even change with time. In the absence of alarm features there is no urgent need for excessive investigations. There is no “cure” but the bothersome symptoms can usually be brought under control by reducing it to a manageable level.

Due the varying symptoms and potential causes, the treatment may require using different methods which include diet, stress and lifestyle management in addition to medications and occasionally surgery. A combination of these treatments is often required for severe cases. Our centre offers a comprehensive and integrated service to manage these disorders comprising of gastroenterologist, gastrointestinal surgeons, psychiatrist and dieticians. Our current resources include:

• Integrated multidisciplinary functional gastrointestinal disorder clinic( “IBS Clinic”)
• Comprehensive psychological intervention for functional gastrointestinal disorders.
• Specialised IBS dietician service for Low FODMAP (Fermentable Oligo- Di-Monosaccharides and Polyols) Diet.

Gastrointestinal function investigations include:

• High resolution esophageal manometry
• 24 hour pH impedance monitoring
• Hydrogen breath test
  
• High resolution anal manometry
• Balloon expansion rectal sensation
• Pudendal nerve terminal latency test
• Endoanal ultrasound
• Magnetic resonance evacuation proctography
• Gastrointestinal transit studies.