An abscess is a designation for a body cavity filled with pus. This is an unpleasant consequence of purulent infectious diseases. It may be painful, and by conservative (non-surgical) means it is hardly treatable. The infection can spread from the abscess cavity throughout the body to start a condition called sepsis.


Abscesses are especially associated with purulent bacterial infections – most frequent abscess cause are groups of bacteria known as staphylococci and streptococci, nevertheless the cause could be virtually any bacterium. There exist even abscesses of fungal origin and abscesses caused by protozoa (e.g., amoebic abscesses). Intravenous drug users are a very vulnerable group of people for abscess development because of many factors – frequent needle punctures into the tissues, low level of hygiene and impaired immune system function in drug- devastated body.

Abscess formation

Abscess forms when bacteria (or other infectious agents) get into the tissues and organs where purulent inflammation arises. Pus is a smelling turbid fluid that contains live and dead bacteria, white blood cells, dead skin debris etc. If our organism is able to quickly deal with the infection, the area demarks as a cavity filled with pus – the abscess. The abscess on one side points to the inability of the immune system to destroy the infection, on the other side it at least shows its ability to stop the inflammation from spreading. After the formation of an abscess three possible scenarios may follow:

  1. Infection in the abscess is suppressed, pus is absorbed and the abscess will heal.
  2. If an abscess is located close under the skin, it can create a tunnel to the surface and evacuate. The tunnel is called a fistula. After emptying the abscess and fistula usually heal but sometimes they may persist.
  3. The infection from the relatively well demarked abscess cans spread into surrounding tissues. Such tissue infection is called phlegmon. The bacteria can spread into the blood causing a very dangerous condition known as sepsis (blood poisoning).


An abscess can occur anywhere in the body (skin, muscle tissue, liver, lungs, kidneys, brain, etc.). If it is located under the skin, it manifests as bumps with red, warm and painful skin above it. Deep tissue and organ abscesses are not visible but they are also painful, cause high temperatures and various functional disorders of affected organ or tissue.


An abscess is most commonly caused by bacteria and thus the logical choice is to use antibiotics. It's true but in it very difficult for antibiotic agents to penetrate into the abscess cavity and their effect is reduced. Of course, antibiotics prevent the infection from spreading and can easy the symptoms. The most effective treatment method is surgery. If possible the surgeon opens the abscess and drains the pus. When drainage is administered the abscess tends to evacuate and heals. Surgeons are very familiar with the Latin proverb “Ubi pus ibi evacua” which can be translated as “When there is pus, evacuate it”.

Jiri Stefanek, MD  Author of texts: Jiri Stefanek, MD
 Contact: jiri.stefanek@seznam.cz
 Sources: basic text sources