An abscess is an accumulation of pus formed under the skin (also called a boil when on the skin) or in deeper body tissue. The cause is almost always an infection by bacterial micro-organisms. The pus is actually the remains of the body tissue that the human immune system has attacked to fight the infection combined with white blood cells (leukocytes) also some of the bacteria. Once the white blood cells are attacking the infected area a lining is formed around the area to prevent the bacteria spreading, and to focus the efforts of the immune system. This lining, called a pyogenic membrane, often then expands to create the rounded abscess that is seen on the skin or within internal organs.
Types of Abscess
There are several types of abscess, each one generally forms on a particular type of body tissue. Abscesses can form anywhere in the body. Common sites for abscesses include breast tissue, gums, and the skin following a burn or cut. However, abscesses can also form on the brain, the liver and on other internal organs.
Abscesses that form under the skin tend to appear in the same areas. The armpit (axilla) is a common spot for an abscess, as is the groin. These areas have large numbers of lymph glands that are responsible for fighting infection and it is probably by no accident that the body’s lymph glands lie so close to the areas most commonly infected.
This is a type of abscess which forms a small abscess cavity under the skin which is then connected to a larger abscess that is deeper under the skin within other body tissues. A channel, called a sinus, connects to the two abscesses.
A dental abscess is pus-filled sac at the root of a tooth. They can be very painful. They are often caused when bacteria enters the pulp of the tooth, which is the region where the blood vessels and nerves enter the tooth. Teeth, like bone, is living tissue and required blood, oxygen and nutrients to remain in good health.
Dental abscesses can result from periodontal disease, which the result of bacterial accumulation in the deep recesses that form between the teeth and the gums.
Treatment is only possible by a skilled dentist. The tooth will often have to be drilled to access the abscess, it will then be drained and then a filling applied to the tooth to prevent further infection, once the infection has been cleared – root canal treatment. In serious cases the tooth has to be extracted.
Common Causes of Abscesses
- Common bacteria – most abscesses are caused by common bacteria such as staphylococci.
- Fungal infections are also sometimes the cause.
- Amoebae (animal parasites) can also lead to infection and the formation of an abscess. These are often the cause of liver abscesses, after contaminated food is eaten.
- Infectious organisms – this is really any organism that enters the bloodstream through a cut to the skin or a bite from an insect or larger animal.
Abscess Symptoms – How to Diagnose
An abscess usually starts to become known due to discomfort or pain in a localised area of the body.
Larger abscesses caused by infection can cause a fever with chills, sweating and a general feeling of being unwell.
Some abscesses may lead to a feeling of intense pressure and red coloured inflammation may be present. A raise in skin temperature, caused by increase blood flow, is also a sign.
Sometimes the only way to diagnose a deep abscess is through imaging techniques such as a CT scan, MRI or isotope scans (radionuclide scanning).
A serious abscess generally requires antibiotics or anti-fungal drugs. It is important to know the cause to treat effectively. There are also antiamoebic drugs for fighting off parasites.
However, as the abscess is lined with a relatively thick and impenetrable layer drugs cannot always easily enter the site of infection from the bloodstream. If an abscess is on the skin then it may simply be cut by a surgeon so that the infected pus can be cleaned off. When internal a drainage tube first needs to be applied before the pus sack is opened. Most abscesses require surgical drainage.
It is not really possible to treat them yourself, so always seek professional medical assistance.
Sometimes an abscess will burst and the infected pus will be dispersed. The immune system will break down any harmful bodies left in the body. However, internal abscesses can cause permanent damage to vital organs. If there is an abscess on the brain or liver, for example, leaving it to burst may result in permanent damage to these organs.