tonsillitis
Meaning of tonsillitis: White patches on inflamed tonsils are widely read as proof of a bacterial cause, though viruses produce them just as readily.
Definition of tonsillitis
Tonsillitis is inflammation of the tonsils, the two pads of immune tissue at the back of the throat, causing sore throat, painful swallowing, fever and swollen neck glands. Most episodes are caused by viruses, and a minority by bacteria, most often group A streptococcus. The tonsils look red and enlarged, and they may carry white or yellow patches.
Does inflammation mean infection?
The ending -itis means inflammation, which is the response of tissue to injury of any kind: redness, swelling, heat and pain. Infection is one cause of that response rather than a synonym for it. Most tonsillitis is infectious in practice, but the organism is usually a virus, including those behind ordinary colds and the virus causing glandular fever. Bacteria account for a minority. The tonsils are lymphoid tissue placed where the mouth opens into the throat, so they meet everything breathed and swallowed, and swelling there narrows an already tight passage.
Can viral and bacterial cases be told apart by looking?
| Feature | Points toward a virus | Points toward streptococcus |
|---|---|---|
| Cough and runny nose | Usually present | Usually absent |
| Fever | Mild or absent | Often marked |
| Neck glands | Mildly enlarged | Tender and enlarged at the front |
| White patches on the tonsils | Common | Common |
| Age group | Any | Commonest in school age children |
No single feature settles it, and the row that misleads most is the fourth. Patches look alarming and are taken as proof of bacterial infection, yet viruses produce them just as often. Scoring systems combine several features to estimate how likely streptococcus is, and a swab or rapid antigen test taken from the tonsil surface is what actually answers the question.
What can develop from it?
Pus can collect between a tonsil and the muscle wall beside it, forming a peritonsillar abscess. That shows as pain concentrated on one side, a muffled voice, difficulty opening the mouth and the soft palate pushed across, and it sits at the severe end of a spectrum beginning as spreading cellulitis in the same tissue. Streptococcal infection can also be followed weeks later by rheumatic fever affecting the heart and joints, or by inflammation of the kidney. Repeated episodes over several years are the usual reason tonsils are removed, a decision resting on frequency rather than on any single attack. Persistent enlargement of one tonsil alone, without pain or fever, is a different finding and is investigated for growths in the oropharynx.
Also known as
Used in a sentence
Examination showed acute tonsillitis with tender lymph nodes in the neck.
Good to know
The appearance of the tonsils does not separate viral from bacterial tonsillitis, since white patches occur in both, which is why swabs and rapid antigen tests exist. Pain concentrated on one side with a muffled voice and difficulty opening the mouth describes a peritonsillar abscess rather than simple tonsillitis.
Word origin
Where “tonsillitis” comes from
From the Latin tonsillae, the tonsils, with the Greek suffix -itis, meaning inflammation.