Conditions: Peritonsillar (or Tonsillar) Abscess

what is a peritonsillar abscess?

A peritonsillar abscess is a collection of pus that forms in the tissues behind a tonsil. While most episodes of tonsillitis do not lead to development of a pertitonsillar abscess, tonsillitis may in some cases progress to abscess formation. A peritonsillar abscess is often associated with significant pain, a change in the voice (described as a “hot potato” voice), significant enlargement of one tonsil, formation of a convex surface by the soft palate, and deviation of the uvula away from midline. Medical imaging, such as with a CT scan, may be undertaken to facilitate diagnosis of an abscess.

An abscess is more than just a severe infection within the tissues. Because an abscess is a collection of pus positioned between tissues/anatomic structures, not within tissues/anatomic structures, there is no blood flow within the abscess. This makes fighting the infection difficult—as the weapons of our immune system and antibiotics are delivered to an area through blood flow. Because of this limitation, all but small abscesses typically require drainage for treatment. While spontaneous rupture and drainage of an abscess may occur, drainage is typically achieved with a surgical procedure.

Less common than a peritoinsillar abscess, a tonsillar abscess or “intratonsillar” abscess is an abscess that forms within a tonsil. Symptoms, signs, diagnosis and treatment of a tonsillar abscess is essentially the same as for a peritonsillar abscess.

It is possible, but uncommon, for both tonsils to be involved with abscess simultaneously. This may make diagnosis by exam more difficult because the lack of asymmetry may incorrectly suggest tonsillitis.

What is a tonsillar or peritonsillar phlegmon? How is it differentiated from an abscess?

A phlegmon is a localized area of inflammation in the soft tissues that has not yet developed into a pus-filled abscess.

It can be difficult and sometimes impossible to discern a tonsillar/peritonsillar abscess from a phlegmon, with examination and even with CT imaging. Sometimes, the definitive diagnosis of abscess versus phlegmon is made by an attempt at drainage; if pus is found, it is an abscess.

What is tonsillitis?

Tonsillitis is inflammation of one or both tonsils, but without abscess formation.

Bacterial superinfection

A superinfection is a second infection superimposed on an earlier one, especially by a different microbe, that is resistant to the treatment being used against the first infection. In the pharynx, the most common scenario is when a virus causes pharyngitis, and then bacteria take advantage of one’s decreased defenses to set up a bacterial infection. This transition from one infection to another may be apparent by a change in symptoms, such as having a sore throat that is improving around day 3-5 but then worsens again thereafter.

other throat Abscesses (including retropharyngeal abscess and parapharyngeal abscess)

A retropharyngeal abscess is roughly midline behind the muscles constricting the throat, and has the potential to expand downwards into the chest. A parapharyngeal abscess is in a deep pocket on a side of the neck near the carotid artery and internal jugular vein.