Pharyngitis: Causes, Diagnosis, Treatment and Prevention
Pharyngitis is inflammation of the pharyngeal mucosa and is one of the commonest causes of sore throat. Most acute cases are viral and self-limiting; group A streptococcal infection is the main bacterial cause considered for targeted antibiotic therapy.
Do not diagnose bacterial pharyngitis from redness or exudate alone. Combine clinical probability, local testing availability and current antimicrobial guidance.
Learning objectives
- Identify infectious and non-infectious causes.
- Recognise streptococcal clues and dangerous alternatives.
- Plan rational investigations and treatment.
- Prevent transmission and complications.
Causes
Rhinovirus, influenza, adenovirus, coronaviruses, enteroviruses and Epstein–Barr virus.
Group A streptococcus; consider diphtheria, gonococcal infection or other bacteria according to exposure and immunisation.
Smoke, allergy/post-nasal drip, reflux, dryness, mouth breathing and voice strain.
Clinical patterns
| Pattern | Suggestive features |
|---|---|
| Viral | Cough, coryza, hoarseness, oral ulcers or conjunctivitis with sore throat. |
| Streptococcal | Sudden sore throat, fever, tender anterior cervical nodes, tonsillar inflammation/exudate and absence of cough. |
| Infectious mononucleosis | Marked fatigue, posterior cervical nodes, tonsillar exudate and possible hepatosplenomegaly. |
| Diphtheria | Adherent grey membrane, toxic appearance and cervical swelling; medical emergency and public-health concern. |
Assessment
- Assess airway, breathing, hydration and sepsis signs.
- Ask about duration, cough/coryza, rash, contacts, sexual exposure, immunisation, medicines and recurrent episodes.
- Inspect mouth, tonsils and posterior pharynx; palpate cervical nodes.
- Look for trismus, unilateral swelling, drooling, neck stiffness or stridor.
Clinical scores such as Centor/FeverPAIN-type approaches may estimate streptococcal probability but do not replace judgement or local policy. Rapid antigen testing or throat culture is used selectively where available.
Treatment
Supportive care
- Fluids, rest, appropriate analgesia and antipyretics.
- Warm saline gargles for suitable older patients.
- Avoid smoke and other irritants.
Antibiotics
Antibiotics are not indicated for uncomplicated viral disease. When group A streptococcus is confirmed or sufficiently likely under local guidance, prescribe the recommended narrow-spectrum regimen, checking allergy and completing the course. Suspected diphtheria, gonococcal infection or deep-neck infection requires urgent disease-specific management.
Stridor, drooling, inability to swallow saliva, severe dehydration, toxic appearance, unilateral bulge with trismus, neck swelling/stiffness, altered voice, respiratory distress or rapidly worsening symptoms.
Complications
- Peritonsillar, retropharyngeal or parapharyngeal abscess.
- Otitis media, sinusitis and cervical lymphadenitis.
- Acute rheumatic fever after group A streptococcal infection.
- Post-streptococcal glomerulonephritis.
- Airway obstruction or sepsis in severe invasive disease.
Prevention
- Handwashing and cough etiquette.
- Avoid sharing cups and utensils during acute illness.
- Keep routine immunisation, including diphtheria protection, up to date.
- Follow local advice on return to school/work after streptococcal treatment.
Review pharyngeal anatomy and adenotonsillitis.
Key examination points
- Most acute pharyngitis is viral.
- Cough and coryza favour a viral cause.
- Group A streptococcus is the key bacterial target for rational antibiotic use.
- Grey adherent membrane suggests diphtheria until assessed.
- Drooling, stridor or deep-neck signs demand urgent care.
References and further reading
For education only. Apply current Uganda Clinical Guidelines and local antimicrobial protocols.
