What is Hepatitis B?
Hepatitis B is a major public health problem in the Asia Pacific region where three quarters of the whole world’s chronic Hepatitis B patients live. Hepatitis B is a DNA virus with a number of sub-types that have some relevance to the severity of hepatitis and the response to treatment.
Heartburn is a symptom whereby patients feel a burning sensation in the middle of the chest, sometimes rising from the upper abdomen into the chest. It can be severe enough to be painful. Often heartburn occurs after eating or when lying down to sleep.
Upper abdominal discomfort is sometimes referred to by patients as “gastric pain”. The medical term is dyspepsia, which means pain or discomfort centred in the upper abdomen.
There can be associated symptoms such as bloating, nausea and fullness after eating. These are very common symptoms and usually caused by disorders of the digestive tract.
Constipation is a common complaint. Technically it is defined by the presence of either straining with hard stools, or fewer than 3 bowel movements per week for at least 25% of the time. Patients usually complain of constipation when it is a relatively recent phenomenon which is a noticeable change from easier motions in the past. Or else they have symptoms of discomfort from constipation such abdominal bloatedness or pain. Such discomfort can even impair appetite.
Tumour markers are substances produced by a tumour or the body in response to a tumour. When released into body fluids, they are detectable by sensitive analytical methods. Tumour markers can be analysed by biochemical, immunochemical or molecular biology based methods.
More patients are asking for screening for cancers as public knowledge about cancers increases. For instance, media reports about the growing rate of colorectal cancer make the public aware that one in twenty Singaporeans could contract colorectal cancer in their lifetime, especially if they have risk factors. The concept of screening means testing people with no symptoms.
Alcohol cannot be stored and must be oxidized, predominantly in the liver. Alcohol metabolism has a limit in the liver, although someone who has been drinking alcohol for some time may induce his liver enzymes thus allowing the liver to metabolise more. Alcohol provides empty calories as energy only with no other contribution to nutrition.
Hepatitis A and B are diseases that can be prevented by vaccination. Hepatitis A does not progress to chronic infection, but morbidity and economic cost are considerable. Two Hepatitis A Vaccines Havrix and VAQTA are available in the market and have protective efficacy of 94% to 100%. Because of cost however, in communities with high endemicity of Hepatitis A and high levels of lifelong natural immunity, it is more cost efficient to screen potential vacinees first to see if they are already immune.
Irritable bowel syndrome (IBS) is a ‘functional’ gastrointestinal disorder. This means that the cause of it is not a specific and identifiable disease entity, but a plausible consequence of disordered functioning of the bowels. Other names for IBS that occur in literature include “spastic colon”, “irritable colon” and “nervous colon”.
Gastroenteritis is a general term which refers to an acute diarrhoeal illness characterised by loose or watery frequent motions, abdominal cramps and perhaps nausea or vomiting. It is usually food and water borne and thus often referred to as 'food poisoning'. It is often contracted during travel to countries where public hygiene and water quality are not as good as that in the home of the traveller and this is commonly known as 'travellers' diarrhoea'. The illness is usually self limiting, but may be debilitating during its course.