Epidemiology
Etiology
- Acute tonsillopharyngitis
- Viral (50–80% of cases): adenovirus, EBV, CMV, HSV, rhinovirus, coronavirus, influenza and parainfluenza viruses, HIV
- Viral pharyngitis is more common than bacterial pharyngitis in both adults (up to 90% of cases) and children (up to 40% of cases).
- Bacterial (15–30% of cases)
- Most common: acute GAS tonsillopharyngitis caused by Streptococcus pyogenes, also known as Group A Streptococcus (GAS)
- Others: Neisseria gonorrhoeae, Corynebacterium diphtheriae
- Viral (50–80% of cases): adenovirus, EBV, CMV, HSV, rhinovirus, coronavirus, influenza and parainfluenza viruses, HIV
Pathophysiology
Clinical features
Acute bacterial tonsillopharyngitis
- Sudden onset of symptoms: fever, sore throat, dysphagia
- Significantly inflamed pharynx
- Pharyngeal and/or tonsillar erythema and edema
- Pharyngeal and/or tonsillar exudates (rare in children < 3 years of age)
- Fibrin deposits appear as white spots on the tonsils.
- Palatal petechiae
- Cervical lymphadenitis
- Absence of cough
Acute viral tonsillopharyngitis
Accompanied by symptoms of a common cold (rhinitis and/or pharyngitis)
Diagnostics
Rapid strep test
- Modality: rapid antigen detection test (RADT) specific for GAS antigens.
- Indications: first-line test in suspected acute bacterial tonsillopharyngitis
- All symptomatic children ≥ 3 years of age and adults (unless symptoms are suggestive of acute viral tonsillopharyngitis)
- Procedure: Swab the patient’s tonsils and the back of the throat.
- Findings
- Identifies the presence of GAS (positive RADT).
- Time to result: 5–10 minutes
Additional laboratory tests
- Antistreptolysin O (ASO) titer
- Elevated levels suggest a previous GAS infection; not helpful to diagnose acute pharyngitis
- Indicated in the workup of nonsuppurative complications of GAS tonsillopharyngitis (e.g., acute rheumatic fever, PSGN).