Epidemiology and Aetiology

  • 70% viral
  • 30% bacterial
  • 90% will recover within a week without treatment
  • Common in children age 5-10 and young adults age 15-25
  • Caused by Group A streptococcus. This is carried in normal healthy throats in the general population. Rates of carriage decline with age, from about 10% of under 14’s to <1% of over 45s.

Presentation and diagnosis

Sore throat!
Use the Centor Criteria to help decide if antibiotics are necessary. There is a 50% chance of being bacterial if:

  • Pus on tonsils (tonsilar exudate)
  • Pyrexia
  • No cough
  • Tender cervical lymph nodes

You should really only give antibiotics to those who meet 3 or 4 criteria.


Investigations aren’t usually necessary. You can to throat swabs for Group A beta-haemolytic streptococcus but this takes a while, and often people are carriers without this being the cause of their tonsillitis.
Some advocate the use of rapid antigen testing from a throat swab, as this only takes a few minutes, but the evidence shows that it does not alter prescribing patterns, and so is probably not useful.


  • Mostly supportive – paracetamol and ibuprofen
  • Avoid giving antibiotics unless four features above are present or if systemically unwell
  • Avoid amoxicillin – as this causes a rash if the patient has glandular fever.
  • Penicillin V (aka phenoxymethypenicillin) is typically used if they meet the criteria. Erythromycin is a good alternative if they are penicillin allergic.


  • Ear pain – not always due to otitis media – can just be referred pain
  • Otitis media – particularly in children



  • Common cold – the common cold will cause similar features and in general practice a lot of patient may request or expect antibiotics. Use the Centor Criteria to decide and to justify your decision.
  • Glandular fever – Epstein Barr Virusaka infectious mononucleosis – typically presents in adolescents or young adults, but children can get it too. Rare in adults. Often accompanied by general malaise and tiredness. Can take several week to resolve, particularly the lethargy and treatment is only supportive. DO NOT GIVE AMOXICILLIN! Rarely can cause a ruptured spleen, or jaundice. Jaundice is usually mild and self-limiting, but the ruptured spleen can be life threatening. The spleen may become enlarged but is highly unlikely to rupture. You may want to ask patients to avoid contact sports or anything that puts them at risk of traumatic splenic injury.
  • Epiglottitis – be wary – will require immediate acute admission.


Tonsillectomy is less common than in past decades, but still routinely performed by ENT surgeons. The tonsils are important lymph nodes that help to fight infection of the upper respiratory tract, and are not ‘useless’ but in most people, can be safely removed.
Surgery is only used in recurrent cases of infection. The goal of surgery is to reduce the frequency of these infections.
There are strict NICE guidelines which stipulate tonsils can only be considered for removal if all four of the following conditions are met:

  • >5 episode tonsillitis in one calendar year
  • Symptoms ongoing for >1 year
  • Episodes are disabling and prevent normal function
  • Tonsillitis is known to be the cause of the sore throats!

Surgery is usually straightforward, but there is a risk of large haemorrhage, which can often occur several hours or days later (be aware when on call covering ENT wards as a foundation doctor!)

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