Sore Throat
Differential Diagnosis
Common Diagnoses
- Mild Viral Pharyngitis (with URTI)
- Tonsillitis/Streptococcal Pharyngitis (‘Strep Throat’)
- Glandular Fever
- Quinsy (Peritonsillar Abscess)
- Oropharyngeal Candidiasis
Occasional Diagnoses
- GORD in adults
- Glossopharyngeal Neuralgia and Cervicogenic Nerve Root Pain
- Trauma: Foreign Body or Scratch from Badly Chewed Crispy Food
- Other Viral or Bacterial Infections (e.g. Vincent’s Angina, Herpangina, Herpes Simplex, Gonorrhoea, HIV Infection)
- Aphthous Ulceration
- Acute or Subacute Thyroiditis
Rare Diagnoses
- Cardiac Angina
- Carotidynia
- Blood Dyscrasia (Including Iatrogenic)
- Epiglottitis
- Diphtheria
- Oropharyngeal Carcinoma
- Retropharyngeal Abscess
Ready Reckoner
Key distinguishing features of the most common diagnoses
| Mild Viral | ‘Strep Throat’ | Glandular Fever | Quinsy | Oropharyngeal Candidiasis | |
|---|---|---|---|---|---|
| Cervical lymphadenopathy | Possible | Yes | Yes | Yes | No |
| Purulent Throat | No | Yes | Possible | Possible | No |
| High Fever | No | Yes | Yes | Yes | No |
| Unilaterally Swollen | No | Possible | No | Yes | No |
| URTI Symptoms | Yes | No | No | No | No |
Possible Investigations
Likely:None.
Possible:Throat swab, FBC, Paul–Bunnell test.
Small Print:Blood glucose and HIV, upper GI endoscopy, biopsy, cardiac investigation (all secondary care).
- Throat swab: Use is controversial, mainly because of low specificity and sensitivity. Practical use only in persistent sore throat or treatment failure.
- FBC: May show atypical lymphocytes in glandular fever; also will reveal any underlying blood dyscrasia.
- Paul–Bunnell test for glandular fever if malaise and fatigue persist.
- Blood glucose and HIV: To rule out diabetes and HIV infection in severe, recurrent or persistent cases.
- Upper GI endoscopy may be necessary to diagnose GORD.
- X-ray/laryngoscopy: If suspicion of foreign body.
- Cardiac investigation: In rare case when referred symptoms cause pain in throat.
- Biopsy of suspicious lesions important to investigate possible malignancy.
Top Tips
- Consultations for severe sore throats usually boil down to a decision whether or not to prescribe antibiotics. There is no easy or reliable way to distinguish clinically between bacterial and viral causes, so the situation becomes an exercise in pragmatism, though the Centor or FeverPAIN criteria may help. Even in ‘true’ streptococcal throats, antibiotic treatment probably only reduces the duration of symptoms by about 24 hours and is unlikely to influence the likelihood of complications.
- Mild sore throat with an URTI is usually just one of a ‘package’ of symptoms presented, along with rhinorrhoea, cough, headache and so on. The cause is invariably viral and antibiotics have no role to play.
- Throat swabs only help management in obscure or persistent cases (and even then usually contribute little).
- In adolescents and young adults whom you decide to treat with antibiotics for ‘strep throat’, explain that the symptoms can also be caused by other infections such as glandular fever. This will help maintain the patients’ confidence in you if they return with the sore throat persisting after the course of antibiotics.
Red Flags
- Remember that this apparently trivial symptom can occasionally herald a serious problem. In particular, enquire about medication (the first sign of drug-induced agranulocytosis may be a sore throat).
- A true foreign body stuck in the throat will lodge in the supraglottic area and may not be seen orally. Refer if in doubt.
- Admit if any suspicion of epiglottitis – and do not examine the throat.
- Consider a possible underlying problem (such as diabetes or immunosuppression) in the younger patient with oropharyngeal candidiasis which has no obvious cause.
- Quinsy can cause a respiratory obstruction. Never attempt conservative management, but admit for surgical drainage.
- Florid ‘tonsillitis’ is unusual in the middle-aged or elderly – consider investigations for a blood disorder or oropharyngeal carcinoma.