Irritable Bowel Syndrome (IBS): Causes, Treatment and Diagnosis

What is irritable bowel syndrome (IBS)?

Do you experience ongoing bouts of stomach pain, bloating, indigestion, diarrhoea or constipation? Have you seen doctors, gone for tests and taken medication, yet have not received satisfactory answers and still live with the symptoms?

It is estimated that close to a million people in Singapore have these symptoms. Patients and doctors often worry that these symptoms could be due to diseases like infections, gallstones, ulcers or cancers. However, every year, the number of people with functional disorders like IBS outnumber the people with gastrointestinal cancers by 500 times.

It is therefore more likely that you might be suffering from irritable bowel syndrome (IBS), a common but complex problem that takes time, expertise and dedication to diagnose and treat.

Common causes of irritable bowel syndrome (IBS)

Our understanding of IBS has progressed beyond the old idea that it is largely a psychological problem due to stress and anxiety. It is now recognised that in many IBS patients the following could also play a role.

1. Infection with intestinal bacteria and parasites.
2. Mild microscopic inflammation.
3. Immune reactions to specific foods.
4. The collection of bacteria found naturally in the intestine (gut microbiota) could be either excessive (small intestinal bacterial overgrowth, SIBO) or unbalanced (dysbiosis).
5. Sensitivity of the nerves and the smooth muscles of the intestine (visceral sensitivity).
6. Inefficient movements or contractions of the gut (gut motility).
7. Increased production of gas in the intestine.

Symptoms of irritable bowel syndrome (IBS)

IBS, along with other functional disorders of the digestive system, is the most common cause of symptoms like:

• abdominal pain
• bloating
• indigestion
• burping
• gas
• constipation
• diarrhoea
• difficult or incomplete bowel movements
• changes in stool consistency

If you are suffering from symptoms like these, please seek help from your doctor for diagnosis and treatment.

How is irritable bowel syndrome (IBS) diagnosed?

There is no specific test to diagnose IBS. Instead, your doctor will first need to take note of your medical history and symptoms.

While the Rome criteria is often mentioned, this is meant for research. In the real world, IBS is not a condition that is diagnosed simply by doing blood or stool tests, x-rays, ultrasound scan or even endoscopy. Instead, IBS can be diagnosed when the doctor carefully listens to the patient's history.

Tests can serve to exclude possible causes of the bowel irritation, which can range from irritable bowel to infection to even cancer. However, many patients are unwilling to go for tests, and sometimes tests are not only unnecessary, but can make a patient's IBS worse. Therefore, the doctor must consider various factors regarding the patient's personal profile, symptoms and history, to decide if further tests are required. It is also important to remember that a person can have IBS along with some other disease like ulcers or cancers.

Several tests may need to be done including:

• Colonoscopy to examine the length of the colon
• Gastroscopy to exclude stomach ulcers, malabsorption and Celiac disease
• X-rays, MRI scan or CT scan to check for pancreatic disease
• Stool tests to check for infection, and inflammation
• Blood tests for gluten sensitivity

Seeking treatment for irritable bowel syndrome (IBS)

Treating IBS always needs a multi-faceted and customised approach. There is no 'one size fits all' kind of treatment plan. It is not enough just to know that a patient has IBS. It is important also to define and find as many factors contributing to the disturbed functions as possible. The combination of factors that are present in any given IBS patient varies from individual to individual. Therefore, treating IBS needs a vastly different and personalised plan for every individual.

To achieve this, the doctor will have to ask detailed and probing questions, sometimes including a carefully selected set of tests, and listen carefully to the patient to get an understanding of the patient's problem. The doctor also needs to help the patient develop a clear understanding of the condition, paying particular attention to lifestyle and psychological factors. Some patients will also benefit from medications, but these have to be carefully selected. Unnecessary surgery should be avoided.

Is there any general diet advice? Are popular detox diets helpful?

The short answer is no, there is no single right diet for IBS patients. The diet that helps one person may actually make another feel worse.

For example, a widespread idea is to eat a high-fibre diet. However, this is unhelpful for many people as a diet high in fibre can further disturb the digestive system. A high-fibre diet is particularly bad for patients suffering from bloating and gas.

Other popular health trends promote the idea of clearing toxins from the body. However, mainstream science does not support the concept of detoxification except in very few circumstances like liver cirrhosis or liver failure. Many herbal detox teas contain a laxative ingredient known as senna, which forms the basis for the over-the-counter laxative known as Senokot. While senna is generally safe, unsupervised use by patients may give rise to tolerance, and thus increasingly higher doses are needed. Senna will also stain the colon lining an abnormal brown colour.

The low FODMAP diet can help many patients especially those who suffer from bloating, gas and diarrhoea. FODMAP is an acronym for fermentable sugars that are found in plant foods and dairy products. This does not mean that patients are forbidden from eating FODMAP containing foods. They just have to be aware that they will be more sensitive to these foods, and should eat them in small quantities when they are not feeling well.

Your doctor may also recommend medication to help with your more troublesome symptoms. These may include:

• Anti-spasmodic medication to reduce intestinal contractions and abdominal pain.
• Some probiotics may also help to reduce bloating, gas and diarrhoea. Some probiotics may have anti-inflammatory property. However, the majority of off-the-shelf probiotics have not been tested for treatment of IBS. Some of these may even aggravate diarrhoea and bloating.
• Certain specialised antibiotics may also be used to overcome SIBO and dysbiosis.
• A class of medications known as prokinetics can help patients who suffer from bloating with constipation. Prokinetics are useful for patients who experience incomplete bowel movements. They can also be used as part of a comprehensive programme to train patients with constipation to develop a regular bowel routine.
• A new class of medications known as secretagogues can be effective for patients who suffer abdominal pain with constipation.
• A class of drugs described as neuromodulators is useful to reduce the visceral sensitivity that contributes to pain, and also to reduce the hypermotility that contributes to the urgent need to rush to the toilet.

As with all forms of medication, you may experience some side effects, and it's best to speak to your doctor about the pros and cons of any recommended therapies.

Is irritable bowel syndrome (IBS) curable?

There is clear evidence that the issues caused by IBS can be largely resolved with proper diagnosis and treatment. Studies report that, with a confirmed diagnosis of IBS, a clear explanation and time spent working with the patient on an individualised treatment plan over a period of up to 6 months, as many as 85% of patients become largely symptom free.

Treating IBS always needs a multi-faceted and customised approach. There is no 'one size fits all' treatment plan hence it is also important to identify as many triggers as possible. For best results, each and every person suffering from IBS needs a personalised plan.

If you would like to find out more about IBS or other digestive disorders, speak to a gastroenterologist.