What is Gastroenterology?

Gastroenterology is the field of medicine covering the diagnosis, treatment and management of disorders of the digestive system, which includes diseases of the oesophagus, stomach, small intestine, colon and rectum, pancreas, gallbladder, bile ducts and liver.

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GOT IT

Liver Stomach Colon Small intestine Rectum Pancreas Bile ducts Oesophagus Gallbladder

Your Rectum

What does the Rectum do?

The rectum is the last part of the large intestine and connects the colon to the anus. colon is the longest segment of the large intestine. The rectum serves as a temporary storage space for faecal material. As the faeces accumulate in the rectum, the rectal wall are gradually stretched until the urge to defaecate occurs.

Common concerns

Common problems associated with the colon include haemorrhoids, inflammation and cancer growths. Haemorrhoids are blood vessels at the anal canal that have become engorged and swollen. They commonly present with the passing of fresh red blood in the stool as well as itch around the anal area. Less commonly, there may be associated pain due to a clot in the haemorrhoid. Rectal inflammation and cancerous growths in the rectum can also present with the passing of blood in the stool as well as pain.

Seek urgent medical advice if you have any of these signs or symptoms

  • Pass blood or mucus in the stool
  • Frequently feel bloated
  • Have a change in your usual bowel habit
  • Experience a feeling of incomplete evacuation
  • Loss of appetite
  • Unexplained weight loss

How to promote your rectum health?

Eating a balanced diet with sufficient fibre, drinking enough water, not smoking, exercising regularly, keeping a healthy weight and managing your stress can help keep your rectum healthy. For individuals without any risk factors, colorectal cancer screening is recommended to begin at age 50 years while those with risk factors should undergo screening at an earlier age.

Your Pancreas

What does the Pancreas do?

The pancreas is an organ located in the upper abdomen and lies behind the stomach. It is J-shaped with the long limb of the J running horizontally across the abdomen. The pancreas is a compound organ in that it produces enzymes that help with digestion of the food that we ingest as well as producing hormones to regulate blood sugar.

Common concerns

Diseases associated with the pancreas include inflammation of the pancreas, pancreatic cancer and diabetes. Inflammation of the pancreas (pancreatitis) results in severe abdominal pain, often necessitating hospitalization. Common causes of pancreatitis are gallstones and excess alcohol consumption. Repeated episodes of pancreatitis can lead to a scarring of the pancreas, a condition known as chronic pancreatitis.

Pancreatic cancer is often difficult to diagnose early as symptoms may not occur until the disease is quite advanced. Risk factors for the development of pancreatic cancer include smoking, obesity, long-term diabetes, chronic pancreatitis and a family history of pancreatic cancer.

Seek urgent medical advice if you have any of these signs or symptoms

  • Persistent or recurrent abdominal discomfort or pain
  • Pass oily stool
  • Yellowing of skin or whites of eyes (a condition known as jaundice)
  • Nausea & vomiting
  • Loss of appetite
  • Unexplained weight loss

How to promote your pancreas health?

Eating a balanced diet with sufficient fibre, drinking enough water, exercising regularly, keeping a healthy weight and managing your stress can help keep your pancreas healthy. Avoid smoking and limit alcohol consumption.

Your Stomach

What does the Stomach do?

The stomach is a muscular bag that lies on the left side of the upper abdomen. Food from the oesophagus enters the stomach where it is broken down by digestive juices and acid produced by the stomach. The muscular contractions of the stomach churn food to help with digestion and also to propel the partially digested food towards the small intestine. Stomach contents exit the stomach through an opening called the pylorus and enters the first part of the small intestine, known as the duodenum.

Common concerns

The most common symptoms which people experience in relation to the stomach are upper abdominal discomfort or pain, nausea or vomiting and bloating and belching.

Other common conditions of the stomach include gastritis, which is inflammation of the stomach lining, and gastric ulcers. A gastric ulcer is a break in the stomach lining which may result in bleeding or perforation of the stomach wall. Gastric ulcers are usually caused by an infection by a bacteria called Helicobacter Pylori and may also be caused by consumption of a group of painkillers known as non-steroidal anti-inflammatory drugs (NSAIDs).

Occasionally gastric ulcers can occur because of stomach cancer. Stomach cancer is one of the most common cancers worldwide and incidence rates are highest in East Asia. Known factors that increase the risk of contracting stomach cancer include Helicobacter pylori infection, smoking, a diet high in preserved meats, as well as family history of stomach cancer.

Seek urgent medical advice if you have any of these signs or symptoms

  • Persistent or recurrent symptoms of upper abdominal discomfort or pain
  • Nausea or vomiting
  • Loss of appetite
  • Unexplained loss of weight

How to promote your stomach health

To keep your stomach healthy, avoid smoking and keep the consumption of preserved meats to a minimum. If there is a family history of stomach cancer, checking whether you are infected with Helicobacter pylori and eradication the infection if present, can be helpful. Find ways to manage your stress levels as stress can also lead to inflammatory conditions of the stomach such as gastritis and gastric ulcers.

Your Oesophagus

What does the Oesophagus do?

The oesophagus is a muscular tube that connects your mouth to your stomach. When you swallow food, the muscles in the wall of the oesphagus contract and propel the food along the oesophagus towards the stomach. At the junction between the oesophagus and stomach, a ring of muscle called the lower oesophageal sphincter helps to prevent the backflow of stomach contents into the oesophagus.

Common concerns

The most common oesophagus related symptoms are caused by gastro-oesophageal reflux disease (GERD). These symptoms include a burning sensation that rises from the stomach up the chest towards the mouth (also known as heartburn) and the regurgitation of sourish fluid. GERD occurs because the lower oesophageal sphincter does not function properly. If left untreated, GERD can cause damage to the oesophagus.

You may experience other symptoms relating to the oesophagus such as pain when swallowing or a feeling that the food or drink swallowed is getting stuck.

Seek urgent medical advice if you have any of these signs or symptoms

  • Persistent or recurrent heartburn
  • Difficulty or pain when swallowing or a
  • Sensation of swallowed food or liquids getting stuck

How to promote your oesophagus health

The oesophagus can be damaged by acid (as in GERD), alcohol or by certain medications. When taking medications, it is advisable to do so in an upright position and drink plenty of water. Drinking liquids which are too hot can also damage the oesophagus.

Your Small intestine

What does the small Intestine do?

The small intestine is a long, coiled muscular tube that extends from the stomach to the large intestine. The digestion and absorption of food mainly takes place in the small intestine. The small intestine is about 6 metres long and is composed of three segments: the duodenum, jejunum and ileum. The first segment after the stomach is called the duodenum and is where semi-digested food from the stomach is further digested by bile and enzymes secreted by the pancreas.

The small intestine is lined with tiny finger-like projections called villi which greatly increase the surface area of the small intestine coming into contact with the digested food, allowing for absorption of nutrients into the bloodstream. The muscular walls of the small intestine move the semi-digested food along the small intestine, mixing them up thoroughly with the digestive juices. Non-absorbed waste product eventually leaves the small intestine and enters the large intestine.

Common concerns

Problems that can occur in the small intestine include dysmotility, bleeding, inflammation, cancerous growths and intestinal obstruction. Dysmotility occurs when the muscular contractions of the small intestine walls are impaired, resulting in symptoms such as distension and bloating. Small intestinal inflammation can lead to pain and the passing of blood and mucus in the stool.

Cancerous growths in the small intestine is less common but can cause obstruction of the intestinal lumen, resulting in abdominal pain and vomiting.

Seek urgent medical advice if you have any of these signs or symptoms

  • Persistent or recurrent abdominal discomfort or pain
  • Pass blood or mucus in the stool
  • Loss of appetite
  • Unexplained weight loss

How to promote your liver health?

Eating a balanced diet with sufficient fibre, drinking enough water, not smoking, exercising regularly, keeping a healthy weight and managing your stress well can help keep your small intestine healthy.

Your Colon

What does the Colon do?

The colon is the longest segment of the large intestine. The small intestine joins the colon at the caecum, a sac-like area at the right lower abdomen. The colon then runs upwards along the right side of the abdomen as the ascending colon, across the abdomen as the transverse colon and then turns down to run down the left side as the descending colon. At the left lower abdomen, the descending colon joins a loop of colon known as the sigmoid colon which then joins the rectum.

The function of the colon is to absorb fluids and salts from the waste products, transforming the liquid waste products from the small intestine into solid faeces. The lining of the colonic wall contains glands that produce mucus to lubricate the faecal material while the muscular walls of the colon propel the faeces towards the rectum.

Common concerns

Problems associated with the colon include constipation, diarrhoea, abdominal gas bloating, inflammation and cancer growths. A large proportion of abdominal complaints relate to disorders of the colon. Many of the symptoms of benign conditions overlap with more serious conditions such as colon cancer.

Colon cancer is one of the most commonly occurring cancer in the world and is the most common cancer in Singapore. Another common condition relating to the colon is Irritable Bowel Syndrome (IBS), a chronic condition characterised by abdominal pain, altered bowel movements and abdominal bloating, in the absence of structural abnormality of the colon. Often dismissed as a nuisance, symptoms of IBS significantly diminishes a sufferer’s quality of life.

Seek urgent medical advice if you have any of these signs or symptoms

  • Persistent or recurrent abdominal discomfort or pain
  • Pass blood or mucus in the stool
  • Frequently feel bloated
  • Have a change in your usual bowel habit
  • Chronic constipation
  • Chronic diarrhoea
  • Loss of appetite
  • Loss of appetite
  • Unexplained weight loss

How to promote your small colon health?

Eating a balanced diet with sufficient fibre, drinking enough water, not smoking, exercising regularly, keeping a healthy weight and managing your stress can help keep your colon healthy. For individuals without any risk factors, colorectal cancer screening is recommended to begin at age 50 years while those with risk factors should undergo screening at an earlier age.

Your Gallbladder

What does the Gallbladder do?

The gallbladder is a muscular pouch that lies under the liver. The function of the gallbladder is to store bile, which is produced by the liver. Bile helps in the digestion of fats. During a meal, the gallbladder contracts to expel the bile, through a tube called the bile duct, into the small intestine where it mixes with the partially digested food. Our body produces more than enough bile for our daily digestion hence the gallbladder itself is not essential.

Common concerns

Problems associated with the gallbladder include gallstones and gallbladder inflammation. Many individuals have gallstones and the majority do not experience any symptoms. The main symptoms caused by gallstones are those of upper abdominal pain, nausea and vomiting, often associated with the consumption of a fatty meal. The gallstones can also cause inflammation of the gallbladder, resulting in right upper abdominal pain and fever.

A gallstone could also be expelled from the gallbladder and get stuck in the bile duct. This may obstruct the flow of bile into the small intestine, causing yellowing of the skin and the whites of the eyes, a condition known as jaundice. A gallstone in the bile duct may also obstruct the pancreatic duct and cause acute pancreatitis.

There are many risk factors for the development of gallstones. These include increasing age, being female, pregnancy, longstanding diabetes, certain medications, obesity as well as rapid weight loss.

Seek urgent medical advice if you have any of these signs or symptoms

  • Persistent or recurrent abdominal discomfort or pain
  • Pass oily stool
  • Yellowing of skin or whites of eyes (a condition known as jaundice)
  • Nausea & vomiting especially with fatty foods
  • Loss of appetite
  • Unexplained weight loss

How to promote your gallbladder health?

Dietary measures to reduce gallstone formation include eating meals low in saturated fat and regular meal timing so as to promote regular gallbladder emptying. Physical activity has been associated with a decreased risk of gallstone formation. Weight reduction in overweight individuals should be gradual.

Your Bile Ducts

What does the Bile Duct do?

Bile is made in the liver and stored in the gallbladder. It is expelled into the small intestine to help digest fat. Bile ducts are tubular structures that carry bile from the liver to the gallbladder and from the gallbladder to the small intestine. Like tributaries of a river, smaller ducts from various segments of the liver join to eventually form the common bile duct which then opens into the small intestine.

Common concerns

Conditions that affect the bile duct tend to result in the obstruction of the bile ducts. Hence these conditions cause similar symptoms such as yellowing of the skin or whites of the eyes, itching, dark urine, light-coloured stool, fatigue, fever, loss of appetite and loss of weight.

Gallstones are the most common cause of an obstructed bile duct. The bile duct can also be compressed externally by inflammation or a cancerous growth in the head of the pancreas. Less commonly, the bile duct can be blocked by cancers of the bile duct or strictures (which are narrowings caused by scarring after infection, inflammation or surgery).

Seek urgent medical advice if you have any of these signs or symptoms

  • Yellowing of skin or whites of eyes (a condition known as jaundice)
  • Dark urine
  • Loss of appetite
  • Unexplained weight loss

How to promote your bile duct health?

Dietary measures to reduce gallstone formation include eating meals low in saturated fat and regular meal timing so as to promote regular gallbladder emptying. Physical activity has been associated with a decreased risk of gallstone formation. Weight reduction in overweight individuals should be gradual.

Avoid smoking as some studies have suggested that smoking increases the risk of developing bile duct cancer.

In Asia, parasitic infection by liver flukes are associated with a higher risk of bile duct cancer. Humans are infected after eating under-cooked fish, with the adult worms laying eggs in the bile ducts. The parasites cause chronic inflammation of the bile ducts, increasing the risk of cancer developing.

Your Liver

What does the Liver do?

The liver is an organ that lies below the ribcage, mainly on the right side. The liver is involved in the digestion of food and in removing toxic substances from our body.

Common concerns

The liver can be damaged by infections, alcohol and excessive fat. Less commonly, liver disease can be caused by genetic factors.

Seek urgent medical advice if you have any of these signs or symptoms

  • Yellowing of eyes and skin
  • Skin itching
  • Dark urine
  • Pale stools
  • Vomiting blood
  • Abdominal swelling and discomfort
  • Ankle swelling
  • Loss of appetite
  • Nausea or vomiting
  • Tendency to bruise easily