Lower Gastrointestinal Bleeding (LGIB)

 



Q1. What are the causes of blood in stool?
Sometimes you may find blood in stool when cleaning yourself. Whenever bleeding occurs in the large intestine, consult a doctor for a detailed examination. Blood in stool most commonly occurs because of bleeding haemorrhoids in the anus, polyps in the last part of the large intestine or tumours causing the stool to mix with blood inside the large intestine. That’s why it is important to pinpoint the exact source of bleeding.
 
Q2. Does dark stool have to do with gastrointestinal bleeding?
Sometimes your stool may look dark or even black in colour. If it is solid and not mushy, the colour change is most likely due to food colouring, iron in health supplements or antacid in over-the-counter medicine. Stool colour will return to normal once you stop taking these health supplements or foods.
 
If the stool is shapeless and mushy like sesame paste, it may be due to structural problems of the stomach. For example, large polyps or ulcers can cause heavy bleeding and black stool. Consult a doctor if black stool or change in stool colour is suspected.
 
Q3. Do stomach pain and anemia also have to do with lower gastrointestinal bleeding?
Changes in bowel movement along with stomach pain are most likely due to inflammation or ulcers in the stomach. If the ulcers cause pain only, the pain is particularly severe after or before meal with upper abdominal discomfort. If the ulcers are already bleeding, the blood will flow faster towards the large intestine and increases peristalsis, causing shapeless stool with colour changes. Patients in severe cases may even have anemia.
 
Q4. What should I do if occult blood is confirmed in a health check-up?
If occult blood is confirmed in a health check-up, the first thing to do is to consult your family doctor or a specialist. If you have undergone colonoscopy or screening before, your doctor will review the past results and discuss with you the next step after evaluation.
 
If occult blood is found in patients aged over 45, both genders with no prior colonoscopy, it is most likely due to structural problems of the large intestine such as haemorrhoids, bleeding polyps, cancer or inflammation. They can all cause occult blood and other abnormal conditions.
 
Q5. What should I do before colonoscopy?
Prior to the colonoscopy, doctors will try to achieve the following:
 
First, the procedure must be safe.
Second, it should give a clear view of the intestine.
Third, it should make patients as comfortable and pain-free as possible.
 
Once you agree to colonoscopy or colorectal screening, you must follow the instructions of your doctor and nurse. Do not eat certain foods 1 or 2 days before colonoscopy such as high-fibre vegetables or fruits. Any food remnants in the intestine may prevent stool for passing when bowel preparation medications are used. If the stool is not cleared and remains in the large intestine, or if it is too dense, it will take longer time for examination and lead to prolonged anaesthesia, and even incomplete examinations.
 
Q6.  How can I prevent colorectal cancer?
Now common in many countries, screening is most recommended at the age of 45 to 50. Despite busy work schedule, you should see a doctor whenever possible and seek early treatment when polyps are detected during screening or clinical examination.
 
Polyps tend to grow and change slowly: it takes 7 to 15 years to grow from a small to large polyp or later develop into cancer. Therefore screening is most effective when performed after 45 in the absence of symptoms. If you are at 50, or have undergone neither colonoscopy nor fecal occult blood test before, consult your doctor for colonoscopy arrangement.
 
Also important is a healthy eating habit. Eat more fruits and vegetables, especially those rich in fibre and nutrients. Exercise regularly and quit smoking.

Check out YouTube videos from HKSH Medical Group for more health information.