16th February 2025

The mouth and pharynx

Pharyngitis and tonsillitis

These are usually caused by viruses but can also be caused by beta-haemolytic streptococci, H. influenzae, M. pneumoniae or C. pneumoniae. Local spread of infection may lead to quinsy (peritonsillar abscess) or otitis media. Beta-haemolytic streptococci (Streptococcus pyogenes) tend to cause severe infection and may rarely lead to various systemic complications, including glomerulonephritis, rheumatic fever, scarlet fever and toxic shock syndrome. The antibiotic of choice is phenoxymethylpenicillin.

Infectious mononucleosis 

Also called glandular fever, this is caused by the Epstein-Barr virus (EBV). In addition to pharyngitis, it may cause fatigue, fever, lymphadenopathy and splenomegaly. Patients have a positive heterophile antibody (Monospot) test, and the blood film shows atypical mononuclear cells. The patient may develop a rash if given certain antibiotics, particularly amoxicillin and ampicillin. Treatment is usually supportive unless there are severe rare complications; these include airway compromise, Guillain-Barré syndrome and splenic rupture.

Ludwig’s angina

This is a rapidly spreading cellulitis that originates in the floor of the mouth, most commonly from a dental infection and spreads to the submandibular space. Causative organisms include viridans streptococci, staphylococci, and oral anaerobes such as Peptostreptococcus, Fusobacterium and Bacteroides. Presenting features include sepsis, airway compromise, drooling, dysphagia and difficulty speaking.

Oropharyngeal candidiasis

Also known as thrush, this occurs most frequently in the immunosuppressed, those who have had recent antibiotics, or those on oral or inhaled steroids. Mild disease is managed with topical antifungals (e.g. nystatin). Oral fluconazole is used for moderate-to-severe disease or with immunocompromise.

Diphtheria

Caused by the Gram-positive bacillus Corynebacterium diphtheriae, respiratory diphtheria has its onset 2 to 5 days after exposure and presents with sore throat, low-grade fever and purulent nasal discharge. Pharyngeal exudates are often noted, and in one third of cases an oral or nasal “pseudomembrane” forms.