114 Tonsil Disease
Most cases of acute tonsillitis are due to a viral aetiology, but some patients will develop a secondary bacterial infection and others will have a primary bacterial pharyngotonsillitis. GPs can determine which patients should be given antibiotics by using the Centor criteria. Patients with significantly enlarged tonsils should be considered for a 2- to 5-day course of intravenous (IV) steroids to reduce the risk of airway compromise.
114.1 Introduction
The tonsils are paired organs situated on the side of the oropharynx between the palatoglossal (anterior tonsillar pillar) and palatopharyngeal folds (posterior tonsillar pillar). They are part of Waldeyer’s ring, a ring of lymphoid tissue consisting of the adenoids, the palatine tonsils and the lingual tonsils, which are embedded in the posterior third of the tongue. The ring is thought to act as a barrier against infection in the first few years of life. The tonsil is enclosed by a fibrous capsule, outside of which is a layer of areolar tissue. This separates the capsule from the pharyngobasilar fascia covering the superior constrictor muscle that forms the tonsil bed. The main blood supply of the tonsil is from the tonsillar branch of the facial artery.
114.2 Acute Tonsillitis
Acute tonsillitis is an infection which primarily affects the palatine tonsil. It may be the dominant feature of an upper respiratory tract infection when it is usually viral in aetiology, or it may present as a primary acute pharyngotonsillitis. The latter is also usually a viral infection involving the lymphoid tissue on the posterior pharyngeal wall and tonsil. Although acute tonsillitis is seen in adults, it is most frequent in childhood, presumably because immunity to common childhood organisms has not been fully established. Common cold and coryza viruses (e.g. influenza, parainfluenza, adenoviruses, enteroviruses and rhinoviruses) are the commonest cause of tonsillitis. An initial viral tonsillitis may predispose to a secondary bacterial tonsillitis (Streptococcus pyogenes, Streptococcus pneumoniae, Haemophilus influenzae, Actinomyces, found in so-called tonsillar debris) and anaerobic organisms.
114.3 Clinical Features
There may be a prodromal illness with pyrexia, malaise and headache for a day before the onset of the predominant symptom, a sore throat. Pain may radiate to the ears and suggest acute otitis media until the ears are examined (referred otalgia) and there may be tender cervical lymphadenopathy. Swallowing may be painful (odynophagia) and the patient’s voice may sound muffled due to enlarged tonsils from acute tonsillar hyperplasia. Acutely enlarged tonsils may cause stertor (noisy breathing due to airway obstruction above the larynx) and acute obstructive sleep apnoea. There may be trismus and dribbling. Children may have abdominal pain and vomiting. Examination shows hyperaemic tonsils with pus and debris in the crypts. Patients with acute tonsillitis presenting to hospital usually have symptoms at the severe end of the spectrum, with significant systemic upset, inability to function normally and inability to maintain adequate hydration. Glandular fever, agranulocytosis, leukaemia and diphtheria are amongst the differential diagnoses in such cases. A full blood count, white cell differential, blood film and liver function tests should be performed in such cases and if diphtheria is suspected, a throat swab is taken.