What is Crohn's disease?

This is a disease of chronic inflammation involving any part of the intestinal tract. It most commonly affects the last part of the small intestine (ileum) and/or the large intestine (colon and rectum). It is relatively uncommon in the Asian population.

Crohn's disease is a chronic condition and may recur at various times over a lifetime. Some people have long periods with no disease, sometimes years, when they are free of symptoms. There is no way to predict when the disease can flare.

What are the types of Crohn's disease?

There are several types of Crohn's disease, classified based on the area of the digestive tract affected:

1. Ileocolitis: The most common type, affecting the ileum (the end of the small intestine) and part of the colon. Symptoms include diarrhoea, weight loss and pain in the lower right abdomen.
2. Ileitis: Involves only the ileum. Symptoms are similar to ileocolitis, and complications such as fistulas or abscesses may occur.
3. Crohn's Colitis: Involves only the colon. It can cause diarrhoea, rectal bleeding and skin lesions.
4. Gastroduodenal Crohn's Disease: Affects the stomach and the beginning of the small intestine (duodenum), causing nausea, vomiting and upper abdominal pain.
5. Jejunoileitis: Characterised by patchy inflammation in the upper half of the small intestine, leading to abdominal pain and cramping after meals.
   

What are the symptoms of Crohn's disease?

Symptoms of Crohn's disease can vary depending on the part of the digestive tract affected and the severity of inflammation. Common symptoms include:

1. Diarrhoea: Often persistent and may be accompanied by urgency.
2. Abdominal pain and cramping: Usually felt in the lower abdomen but can vary depending on the area affected.
3. Fatigue: Due to inflammation, poor nutrient absorption or lack of sleep caused by discomfort.
4. Weight loss: Resulting from poor nutrient absorption or loss of appetite.
5. Fever: A mild fever may occur during flare-ups.
6. Blood in the stool: In cases where the intestine is bleeding, causing dark or bloody stools.
7. Reduced appetite: Caused by discomfort or pain leading to unintentional weight loss.
8. Mouth ulcers: Sores may appear in the mouth during flare-ups.
9. Perianal disease: Including fissures, fistulas or abscesses around the anal area.
   

How can Crohn's disease be controlled?

There is no way to prevent Crohn's disease, but lifestyle changes can help manage symptoms and reduce flare-ups:

1. Dietary changes: Avoid trigger foods and focus on a balanced, digestible diet.
2. Quit smoking: Smoking worsens Crohn's and quitting can reduce flare-ups.
3. Stress management : Techniques like exercise or meditation can help manage stress and symptoms.
4. Medications: Prescribed treatments help control inflammation and maintain remission.
5. Regular medical care: Regular check-ups help monitor and adjust treatments.
   

What causes Crohn's disease?

The cause of Crohn's disease is unknown. However, it is believed to result from a combination of various factors. These include an abnormal immune response, where the immune system mistakenly attacks healthy cells in the digestive tract, and environmental factors that may trigger inflammation. Genetic predisposition also plays a role.

What are the risk factors for Crohn's disease?

The risk factors for Crohn's disease include:

1. Family history: Having a close relative with Crohn's increases the likelihood of developing the condition.
2. Smoking: Smoking is strongly linked to a higher risk and severe forms of Crohn's disease.
3. Age: Although Crohn's can occur at any age, it is more commonly diagnosed in people under 30.
4. Ethnicity: People of European, particularly Ashkenazi Jewish descent, have a higher risk.
5. Environmental factors: Living in urban or industrialised areas or in northern climates, may increase the risk.
6. Nonsteroidal Anti-Inflammatory Drugs (NSAIDs): These medications can worsen inflammation in the digestive tract, potentially triggering or exacerbating symptoms.

These factors may contribute to the likelihood of developing Crohn's disease, but they do not directly cause it.

How is Crohn's disease diagnosed?

Crohn's disease is diagnosed medical history, physical examination and various tests to confirm inflammation in the digestive tract. The diagnostic process typically includes:

1. Blood tests: To check for signs of inflammation, infection or anaemia, which are common in Crohn's disease.
2. Stool tests: Used to detect blood or infections in the stool, helping to rule out other conditions.
3. Endoscopy and colonoscopy: A camera is used to examine the inside of the digestive tract, allowing doctors to see inflammation, ulcers or other abnormalities. Tissue samples may be taken for analysis.
4. Imaging tests: Tests such as MRI, CT scans or intestinal ultrasounds may be used to view the digestive tract and identify areas of inflammation or blockages.
5. Capsule endoscopy: A small camera in a capsule is swallowed, allowing detailed images of the small intestine to be taken to help identify areas of Crohn's disease.
   

How is Crohn's disease treated?

Initial treatment is with medication. The most common drugs used are steroids such as prednisolone, and various anti-inflammatory agents. The drugs do not "cure" Crohn's disease (there is no "cure" available yet), but the drugs are used to relieve its symptoms and may help to avoid recurrence.

In more serious cases, stronger drugs such as azathioprine, biologics or small molecules may be used. However, these drugs have more side effects and suppress the immune system, making the patient more prone to infection.

In more advanced or complicated cases of Crohn's disease, surgery may be recommended.

Emergency surgery is performed when complications, such as a perforation of the intestine, obstruction (blockage) of the bowel, or massive bleeding occur with Crohn's disease. Operations may also be needed in patients who do not respond to medication, patients with abscess formation, fistulas (abnormal communication from the intestine), and patients with severe anal disease.