How does a sore throat happen?
Sudden onset of sore throat in an otherwise well person (acute sore throat) is due to an infection of the pharynx. This is the name for the whole throat, all the way from the back of the nose, down past the back of the mouth, and on down to the voice box. It is therefore called pharyngitis. This infection is caught from contact with another infected person.
In the top of the pharynx there is a circular ring of lymph tissue called Waldeyer’s ring. This ring has the following parts:
- At the back of the mouth are the two (palatine) tonsils — right and left — which is what everyone thinks of as the ‘tonsils’.
- At the back of the nose are the (pharyngeal) tonsils, otherwise known as the ‘adenoids’. These can be a particular problem in children, where they can cause ear infections, as they sit very close to the opening of the Eustachian tube where the middle ear connects to the nose (see our Ear Infections leaflet). If they become particularly enlarged through repeated infection, they can also cause snoring and difficulty breathing through the nose.
- There are also less well-defined collections of lymph tissue around the back of the tongue (lingual tonsils) and around the openings of the Eustachian tubes (tubal tonsils), which are also at the back of the nose close to the adenoids.
All these structures act as a filter to the viruses, bacteria and fungi we breathe in through the nose and mouth all the time, but if one of these bugs is particularly unpleasant it may overwhelm these defences and cause the symptoms we know as pharyngitis. As the infecting organism affects all these structures, we often feel pain and discomfort around the whole of Waldeyer’s ring.
What causes pharyngitis?
In up to 80% of cases, pharyngitis is due to a virus associated with an upper respiratory ‘cough and cold’-type infection. It is therefore often associated with other typical viral symptoms such as a raised temperature, muscle aches and feeling generally mildly unwell. These infections are usually short-lived, and as a consequence many are self-limiting and do not require antibiotics. Treatment is to relieve the symptoms with painkillers and temperature-lowering drugs such as paracetamol, and aspirin (not in children) or aspirin-like drugs (NSAIDs) such as ibuprofen, although these should be avoided in asthmatics. Topical anaesthetics given as sprays or mouthwashes (e.g. Difflam) may also help by numbing the throat.
Bacteria also cause sore throat, but tend to give worse symptoms and occur in younger adults and children (under 15 years old). To help you distinguish whether your acute sore throat is viral or bacterial, people with bacterial infections have a higher chance of also having other symptoms, such as:
- Cough
- Enlarged, painful lymph glands in the neck
- High temperature
- Swollen or mucky-looking tonsils
These patients, with more severe symptoms (indicating that the infection may well be due to bacteria), are far more likely to benefit from treatment with antibiotics.
Fungi can also cause sore throat, but this is more unusual in normally healthy people. It can, however, be seen in people who use steroid inhalers for asthma and don’t wash their mouth out thoroughly after use.
Whatever the cause, acute sore throat may mainly affect the nose (nasopharyngitis, which is usually what happens in the common cold) or the tonsils (pharyngotonsillitis), where there may be pain and a pussy appearance around the tonsils at the back of the mouth (commonly called tonsillitis). Rarely, inflammation of the tonsils like this can be associated with other, more severe specific viral infections such as glandular fever, which affects the lymph tissues throughout the body — of which Waldeyer’s ring, and thus the tonsils, are only a part.
Sometimes a severe episode of bacterial tonsillitis can lead to the formation of an abscess (a collection of pus, like a boil) next to the tonsil at the back of the mouth, called a quinsy. Unless caught very early, a quinsy needs a small operation to lance and drain it. This can usually be performed by an ENT specialist with you awake, using numbing spray and/or a small injection of local anaesthetic, but it may then require a day or so in hospital afterwards. If you have more than one episode of quinsy in conjunction with tonsillitis, then tonsillectomy is probably required.
What causes chronic sore throat?
If the sore throat continues for a prolonged period, or doesn’t have the characteristics of an infective cause as described above, then it is described as ‘chronic’. If this is the case, other causes should be sought by your GP, usually with the help of an ENT specialist like us. Common causes of this issue include:
- Long-standing acid reflux, whereby acid comes up from the stomach into the back of the throat, causing constant irritation (see our Swallowing Difficulty and Laryngopharyngeal Reflux leaflet).
- Long-standing rhinitis and sinusitis (inflammation and infection in the nose and sinuses), with infected mucous dripping down the back of the throat (see our Rhinitis, Sinusitis and Nasal Polyps leaflet).
- Food debris and secretions called tonsilliths, which may collect in particularly pitted tonsils, causing soreness, infection and bad breath.
Lastly, but very importantly, a small percentage of people with persistent, constant sore throat may have a throat cancer. This is more common in smokers, particularly those who also overindulge in alcohol. If your sore throat lasts for more than six weeks, you should seek an appointment to see us for a thorough examination of your throat.
Do I need my tonsils out (tonsillectomy)?
Tonsillectomy is the operation to remove the (palatine) tonsils (see our Tonsillectomy leaflet). It is only needed if the sore throats you or your child are experiencing are recurrent (causing time off work or school) and/or severe and constant (sometimes called ‘chronic tonsillitis’). The tonsils may also cause other problems due to their sheer size, which may also require tonsillectomy.
For your interest, here are the 2015 Kent and Medway NHS criteria for tonsillectomy:
- Five or more documented episodes of sore throat per year, with problems for a year or more.
- Episodes of sore throat that are ‘disabling and prevent normal functioning’.
- Two or more episodes of quinsy.
- Severely enlarged tonsils, causing blockage of the airway and breathing difficulty, or obstructive sleep apnoea while asleep (see our Snoring and Obstructive Sleep Apnoea leaflet).
If you think you or your child fulfil any of these criteria, you may benefit significantly from tonsillectomy. Sometimes (particularly in children) tonsillectomy is combined with removal of the adenoids (see our Adenoidectomy leaflet). The other parts of Waldeyer’s ring are not removed during tonsillectomy, but do not generally cause problems like the true palatine tonsils.
Following tonsillectomy, you will still get sore throats with any respiratory infection, like the rest of the population, but you will not get tonsillitis — so you will not get the severe throat pain and inflammation during bouts of tonsillitis that you had before. If there were problems with airway blockage due to the physical size of the tonsils, these will be cured: the tonsils do not grow back. There is no evidence that tonsillectomy has any effect on the ability of you or your child to resist or fight infection in the future; indeed, by the time they are removed in appropriate patients, the tonsils themselves are a hive of infection that the body can never fully get rid of, and which are themselves causing the repeated sore throats and tonsillitis.