Tonsillitis is the second most common presenting condition in general practice for the 5-15 age group and the eighth most common overall in the UK.
'Sore throat' has an annual incidence of 100 in 1,000, with tonsillitis accounting for approximately 32 in 1,000 patients per year.
Signs and symptoms
Confusion exists over the term 'tonsillitis' as, although it is a parenchymal infection of the palatine tonsils, it can occur in isolation or as part of a generalised pharyngitis.
In general practice, the usual presenting symptom of tonsillitis is a sudden-onset sore throat with associated features of odynophagia, pyrexia and tonsillar exudates, and is more common in 5-15 year olds.
Other symptoms are tonsillar erythema, enlargement, anterior cervical lymphadenopathy and referred otalgia, in addition to headache, halitosis and vomiting. Tonsillitis is viral in the majority of cases and bacterial in 10 to 30 per cent of cases.
Viral or bacterial
The prevalence of bacterial tonsillitis, most commonly due to group A beta-haemolytic streptococci (GABHS), is 15-30 per cent in children with sore throat and 5-15 per cent in adults.
Bacterial tonsillitis can occasionally cause rheumatic fever and acute glomerulonephritis, which can be prevented by penicillin. Less common bacterial pathogens are group C beta-haemolytic streptococci (5 per cent) with rarer bacterial causes including Mycoplasma pneumoniae and Neisseria gonorrhoeae.
Cytomegalovirus infection may also result in the clinical picture of infectious mononucleosis, and the differential diagnosis also includes toxoplasmosis, HIV, hepatitis A, rubella and diphtheria.
It is difficult to differentiate between viral or bacterial aetiology. Rapid antigen testing and bacterial culturing both have low sensitivities and are not recommended (except in those at risk of complications of GABHS-tonsillitis).1
Blood testing should include an infectious mononucleosis screen. The diagnosis of tonsillitis is clinical. Centor criteria will aid in the diagnosis or exclusion of GABHS-tonsillitis and determine whether antibiotics are an option.
Centor criteria includes: tonsillar exudate; tender anterior cervical lymph node; absence of cough and a history of fever. Presence of three of these clinical signs suggests the chance of the patient having GABHS is 40-60 per cent, so the patient may benefit from antibiotic treatment. Absence of three of four Centor criteria suggests there is an 80 per cent chance that the patient does not have a streptococcal sore throat and antibiotics are unlikely to benefit.
Tonsillitis usually resolves in one week with no sequelae. This, in addition to poor evidence from research, has made the management of tonsillitis controversial.
NICE guidelines recommend antibiotics should not routinely be given for tonsillitis.2 In patients fulfilling three or more Centor criteria there is an option of antibiotics, which is also recommended for those who are systemically unwell, with complications (such as quinsy) or those at serious risk of complications due to comorbidity (heart, lung, renal, liver or neuromuscular disease, immunosuppression, cystic fibrosis and children who were born prematurely).
Penicillin is the antibiotic of choice. Ampicillin-based antibiotics, including co-amoxiclav, must be avoided as first line treatment due to the risk of causing a non-allergic rash in those with infectious mononucleosis. For those who are allergic to penicillin, erythromycin should be offered.
Referral to secondary care
Patients with acute tonsillitis not able to maintain an oral intake or those with complications, such as peritonsillar cellulitis or quinsy, should be referred to secondary care.
Patients with more than five episodes per year who want a tonsillectomy may be referred for ENT specialist opinion.
Before (top) and after (below) tonsillectomy; one of the most common surgical procedures
Tonsillectomy is one of the most common surgical procedures performed in the UK. Indications for tonsillectomy may include recurrent acute or chronic tonsillitis, peritonsillar abscess and pharyngeal obstruction/obstructive sleep apnoea.
The benefits have to be weighed against the risks of perioperative morbidity and postoperative haemorrhage. SIGN guidelines recommend that the following should be indications for tonsillectomy:
- Sore throats caused by tonsillitis.
- Five or more episodes of sore throat per year.
- Symptoms for at least a year.
- Episodes of sore throat that are disabling and prevent normal functioning.1
Serious bleeding is a real risk and accounts for the rare deaths which happen after tonsillectomy.
For tonsillectomy versus no surgery in adults, a systematic review only identified one eligible RCT showing surgery 'may be more effective at reducing the frequency and duration of sore throat at five to six months, but we don't know the long-term effects'.3
There are three systematic reviews of tonsillectomy in children.
The most recent systematic review found tonsillectomy significantly reduced episodes of sore throat compared with control at one to three years.
However, the systematic review concluded that there was little clear evidence of clinical effectiveness and cost effectiveness of surgical or medical management (in either adults or children).3
A recently published RCT examining the cost effectiveness of tonsillectomy in children in comparison with standard non-surgical management has shown tonsillectomy reduced the likelihood of having an episode of sore throat by 30 per cent in the first year and 46 per cent in the second year.
Surgery also reduced the mean number of sore throats by 33 per cent in the first year and 73 per cent in the second year. GP consultations were also reduced, resulting in a £261 saving per episode of sore throat avoided.4
- Mr Ahmad is a specialist registrar in ENT and Mr Hawthorne is a consultant ENT surgeon at James Cook University Hospital in North Yorkshire.
|Viruses causing tonsilitis|
1. Scottish Intercollegiate Guidelines Network (SIGN). 2010. Management of sore throat and indications for tonsillectomy. Edinburgh, SIGN. Available from www.sign.ac.uk/pdf/sign117.pdf
2. NICE. Respiratory tract infections - antibiotic prescribing. CG69. London, NICE, 2008. Available from www.nice.org.uk/nicemedia/live/12015/41323/41323.pdf
3. Burton MJ, Glasziou PP. Tonsillectomy or adeno-tonsillectomy versus non-surgical treatment for chronic/recurrent acute tonsillitis. Cochrane Database Syst Rev 2009, Issue 1. Art No:CD001802. DOI: 10.1002/14651858.CD001802.pub2.
4. Lock C, Wilson J, Steen N et al. North of England and Scotland Study of Tonsillectomy and Adeno-tonsillectomy in Children (NESSTAC): a pragmatic randomised controlled trial with a parallel non-randomised preference study. Health Technol Assess 2010; 14: No13.