Is it Inflammatory Bowel Disease (IBD) or Irritable Bowel Syndrome (IBS)?

Dr Kelvin Thia, gastroenterologist at Mount Elizabeth Hospital, gives us an overview of each condition and their differences.

What is inflammatory bowel disease (IBD)?

Inflammatory bowel disease (IBD) is a chronic gastrointestinal disorder whereby patients typically suffer from abdominal pain, diarrhoea and rectal bleeding. It could also give rise to nutritional deficiencies, weight loss and symptoms involving the eyes, joints and skin.

IBD most commonly comes in 2 main forms – ulcerative colitis (UC) where inflammation is confined to the colon, and Crohn's disease which can involve any part of the gastrointestinal tract. Complications associated with IBD include bowel cancer, severe bleeding and surgery required for obstruction or rupture of the intestines.

IBD used to be considered a 'white man's disease', but no longer. Recent studies suggest a 5-fold increase in disease cases over the past 2 decades in Asia. Every year, we encounter about 100 newly diagnosed cases locally. This rising trend in IBD may be linked to modernisation, and environmental factors such as diet.

Risk factors of IBD

A diet rich in animal protein, fat and sugar appear to be associated with IBD risk. Genes certainly play an important role together with abnormal host immune system with the gut microbiota. A well-known risk factor is smoking which can worsen symptoms and increase the risk of complications in Crohn's disease.

Diagnosis of IBD is based on a combination of clinical symptoms, laboratory, radiologic, endoscopic and histologic investigations. Making an early diagnosis of IBD is important as any delay can lead to a higher risk of complications. Patients with IBD are also less likely to respond to therapies when the disease had been poorly controlled for years. Treatment of IBD is usually lifelong and involves anti-inflammatory and various immunosuppression medications.

What is irritable bowel syndrome (IBS)?

Irritable bowel syndrome (IBS) on the other hand is a functional disorder (not due to structural abnormality like inflammation) which is estimated to affect between 10 to 20% of the community.

Patients usually experience abdominal discomfort, diarrhoea or constipation symptoms due to bowel wall hypersensitivity. Symptoms can vary in intensity and be intermittent, but remain stable over time.

As IBS is a benign condition, it does not lead to serious health issues or complications requiring surgery, like what can happen in IBD patients.

However, symptoms in IBS can still be troublesome and has been shown to affect the quality of life significantly in sufferers. There are many treatment options including lifestyle and diet management available to help those struggling with IBS, hence there is no need for anyone to suffer in silence.

A test called the stool calprotectin can be helpful to measure bowel inflammation which is present in IBD and not in IBS sufferers. This stool test can be useful in the preliminary assessment since symptoms of IBD and IBS can be similar in the early stages and may be difficult to differentiate. If the stool calprotectin test is abnormal, patients would often be advised to undergo a colonoscopy for further evaluation.