Localized collection of pus in a cavity in the deeper layers of the skin or within the body, formed from tissues broken down by white blood cells (leukocytes) in response to inflammation caused by bacteria. A wall develops, separating the thick yellowish pus from the extracellular fluid of nearby healthy tissues. Rupture of the abscess allows the pus to escape and relieves swelling and pain. Treatment consists of cutting into the wall to drain the pus and giving antibiotics. If infective contents enter the bloodstream, they may be carried to remote tissues, seeding new abscesses.
Learn more about abscess with a free trial on Britannica.com.
An abscess is a collection of pus (dead neutrophils) that has accumulated in a cavity formed by the tissue on the basis of an infectious process (usually caused by bacteria or parasites) or other foreign materials (e.g. splinters, bullet wounds, or injecting needles). It is a defensive reaction of the tissue to prevent the spread of infectious materials to other parts of the body.
The organisms or foreign materials kill the local cells, resulting in the release of toxins. The toxins trigger an inflammatory response, which draws large numbers of white blood cells to the area and increases the regional blood flow.
The final structure of the abscess is an abscess wall, or capsule, that is formed by the adjacent healthy cells in an attempt to keep the pus from infecting neighboring structures. However, such encapsulation tends to prevent immune cells from attacking bacteria in the pus, or from reaching the causative organism or foreign object.
Abscesses must be differentiated from empyemas, which are accumulations of pus in a preexisting rather than a newly formed anatomical cavity.
The abscess should be inspected to identify if foreign objects are a cause, which may require their removal. If foreign objects are not the cause, a doctor will incise and drain the abscess and prescribe painkillers and possibly antibiotics.
Surgical drainage of the abscess (e.g. lancing) is usually indicated once the abscess has developed from a harder serous inflammation to a softer pus stage. This is expressed in the Latin medical aphorism: Ubi pus, ibi evacua.
In critical areas where surgery presents a high risk, it may be delayed or used as a last resort. The drainage of a lung abscess may be performed by positioning the patient in a way that enables the contents to be discharged via the respiratory tract. Warm compresses and elevation of the limb may be beneficial for a skin abscess.
In anorectal abscesses, primary closure healed faster, but 25% of abscesses healed by secondary intention and recurrence was higher.
To prevent recurrent infections due to Staphylococcus, consider the following measures:
Like other abscesses, perianal abscesses may require prompt medical treatment, such as an incision and debridement or lancing.
Abscesses: potentially serious infection: these pus-filled skin eruptions most commonly occur in intact, roaming male cats. Here are the signs to look for.(HEALTH)
Mar 01, 2011; For several days, your cat has been acting oddly, lolling about the house, uncharacteristically lethargic, off his food and...
Abscesses: signs of trouble: these pus-filled skin eruptions most commonly occur in intact, free-roaming male cats. Here's why.(Health)
Aug 01, 2008; [ILLUSTRATION OMITTED] For several days, your good old cat has been acting oddly, lolling about the house, uncharacteristically...