Dr. Widjaja Luman
Consultant Gastroenterologist and General Physician
B Sc (St. Andrews), MB ChB (Man), MRCP (UK), M.D. (Edin),
CCST (UK), FRCP (Edin)
(Ahli penyakit pencernaan dan hepar)
All of us will experience abdominal pain of greater or lesser severity at some time or other. In most instances, the episodes of pain are mild, transient and not life threatening. Perhaps the most common cause of abdominal pain is abdominal cramp due to increased bowel contraction before defaecation.
Our abdominal cavity contains many organs such as:
- Small and large intestines
- Gynaecological structures (ovaries and uterus)
Disorders in any of the above organ and structure can give rise to abdominal pain. Disorders can be due to dysmotility (problem with bowel contraction), infection (bacteria or viral), inflammation (usually due to auto-immune disorder), growth (benign or malignant) causing obstruction, rupture of the bowel (perforation) and ischaemic bowel (problem with blood flow).
Nature of abdominal pain
Abdominal pain can be diffuse (all over abdomen) or localized to certain part of abdomen (upper or lower abdomen). It can be described as dull discomfort, cramp, burning or bloating. It can be acute (sudden in onset) or chronic (insidious, intermittent and long standing over several months). In general, acute and severe abdominal pain is more likely to be due to serious pathologies such as inflammation or perforation of organs (gallbladder or appendix), or bowel obstruction. Urgent medical attention and treatment is required.
Common causes of abdominal pain
The most common cause of chronic abdominal pain is perhaps due to irritable bowel syndrome (IBS). It is also commonly described by your physician as functional disorders as there is no visible disease in the bowel causing the pain. This is in contrast to organic causes where there is structural (such as tumour) or inflammatory abnormality. IBS is believed to be caused by increased bowel contraction and increased sensitivity of nerve endings to this contraction. Sufferers usually describe the pain as diffuse abdominal bloating and cramp. It can be associated with constipation or diarrhoea. The condition often worsens at time of emotional stress. IBS does not cause you ill health but it impairs your quality of life.
Peptic ulcer disease is due to ulcers of the stomach or duodenum. It is commonly caused by bacteria called Helicobacter pylori and painkillers (non steroidal anti inflammatory drugs; NSAIDs). The pain is usually chronic in nature and is located at upper abdomen. It is commonly described by sufferers as dull, gnawing discomfort. It can be worsened or eased off by meals. It can also be associated with nausea. Peptic ulcer disease can sometimes lead to life threatening complications such as bleeding or perforation. In this situation, the abdominal pain would be acute in onset and severe.
An uncommon but increasing cause of chronic abdominal pain locally in Singapore is due to inflammatory bowel disease (IBD). There are two forms of IBD: ulcerative colitis and Crohns disease. The pain caused by IBD is located at lower abdomen and is described by sufferers as intermittent cramp. There is associated weight loss and diarrhea. Passage of blood in stool is common.
A gynecological problem is suspected in a female with chronic lower abdominal pain if there is associated abnormality of the periods or if the pain tends to occur at a particular phase of the menstrual cycle.
As mentioned previously, acute abdominal pain is usually due to organic pathologies. It is called acute abdomen and often requires emergency treatment.
The often feared cause of acute abdominal pain is acute appendicitis. The appendix is is a small, pouch-like sac of tissue that is located in the first part of the colon (cecum) in the lower- right abdomen. When it becomes inflamed (acute appendicitis), it causes pain at centre of abdomen and as the inflammation progresses, the pain will progress to right sided lower abdomen and becomes more severe. It becomes worse on touching the abdomen, on movement or even on breathing or coughing. There may be vomiting and fever. Emergency surgery is required as there is risk of perforation of the inflamed appendix.
Gallstones are very common and usually do not give rise to pain. However, gallstones may give rise to infection of the gallbladder (acute cholecystitis) and may cause obstruction of bile flow. Gallbladder stones give rise to acute, severe, right sided upper abdominal pain lasting up to several hours, sometimes going to the back or right shoulder. It may cause yellowing discolouration of the skin and dark urine if there is obstruction of bile flow (jaundice). Urgent surgery is required for acute cholecystitis.
Infective gastroenteritis or food poisoning usually causes acute abdominal cramp all over abdomen. It can be caused by bacteria or virus in contaminated food. Usually there are associated fever, nausea / vomiting and diarrhea.
A relatively common cause of acute abdominal pain that does not arise from the alimentary tract is kidney stone. It is due to a stone passing down from the kidneys to the ureter. It results in excruciating pain lasting up to hours, usually on one side of abdomen with radiation of pain into groin on the same side. The urine may turn dark due to the presence of blood.
One life threatening cause of severe, acute abdominal pain is due to ruptured abdominal aortic aneurysm. Aortic aneurysm is caused by dilatation of aorta (the big blood vessel in the abdomen) due weakening of its wall. It can rupture with seepage of blood into the abdominal cavity. The pain is acute and severe and is associated with loss of consciousness due to drop in blood pressure as a result of blood loss. This condition usually happens in the elderly group. Mortality rate is high in this condition.
Malignant disorders causeing abdominal pain
Stomach and pancreatic cancer causes pain at upper abdomen. However, the pain becomes progressively more severe with time (over months). Sufferers of stomach cancer commonly suffer from anaemia (lack of red blood cell) and this can lead to easy fatiguability and breathlessness on exertion. In malignant causes of abdominal pain (stomach / pancreatic / liver colon cancer), sufferers often experience loss of appetite, unintentional weight loss and lethargy as well.
Colon cancer does not cause symptom until advanced stage of the disease. The pain is caused by invasion of the cancer into surrounding organs or by intestinal obstruction. Other symptoms of colon cancer are change of bowel habits and bleeding into stool. Unfortunately all these symptoms happen at late stage of the disease. Thus the importance of colon cancer screening for at risk age group.
Tips for the Patient with Abdominal Pain
It is important for patients and doctors alike to differentiate between the functional causes of pain, which are fully compatible with good general health, and the organic causes, which usually require medical treatment. In particular, patients with acute abdomen must be identified as urgent medical treatment is required.
Mild abdominal discomfort can be treated by simple antacid preparations, anti spasmodics or laxative available over the counter. Organic diseases should be suspected if the pain is persistent or becomes progressively worse over the course of time. Organic diseases are also more likely if there is other symptoms such as loss of appetite, unintentional weight loss, constant nausea / vomiting, bleeding in stool, anaemia and yellowing of the skin. These are called alarm features. In such cases doctors should be consulted so that appropriate tests can be carried out to diagnose the cause of abdominal pain. Urgent medical attention should be sought when abdominal pain is acute ( sudden in onset) and excruciating or unremitting. This is especially if there is also associated symptoms of persistent vomiting and high fever. All these symptoms suggest problem of acute abdomen and urgent medical attention is warranted.