Tonsillitis
Tonsillitis is inflammation of the palatine tonsils, most often viral but with group A Streptococcus as the dominant treatable bacterial cause, diagnosed clinically and risk-stratified with the modified Centor criteria before antigen or culture testing guides antibiotics.
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What this article covers
- Overview
Inflammation of the palatine tonsils (pharyngotonsillitis): sore throat with tonsillar erythema, enlargement, and often exudate, distinguished from other pharyngitis clinically by tonsillar findings driving the exam.
- Epidemiology
Most common in school-age children: streptococcal pharyngotonsillitis is most frequent in children roughly 6 to 12 years of age, though viral tonsillitis occurs at all ages.
- Risk factors
Close-contact settings: school attendance, daycare, and household contact with a confirmed GAS case are the strongest exposure risks for bacterial tonsillitis.
- Pathophysiology
Direct mucosal invasion: viral pathogens (rhinovirus, coronavirus, adenovirus, influenza, coxsackievirus, herpes simplex virus, EBV, CMV, acute HIV) infect the pharyngeal and tonsillar mucosa, producing erythema and variable exudate.
- Clinical features
Sore throat with tonsillar findings: erythematous, enlarged tonsils, with or without exudate, is the defining local sign; odynophagia is typically the dominant symptom.
- Differential diagnosis
streptococcal-pharyngitis: the specific GAS etiology; discriminated by a high modified Centor score confirmed with a positive RADT or culture.
- Diagnosis
This is a clinical diagnosis established by history and oropharyngeal exam, risk-stratified with the modified Centor criteria; testing then targets the treatable bacterial cause.
- Management
First, apply the modified Centor score; a score of 0 to 1 means supportive care alone, no testing or antibiotics.
- Complications
Peritonsillar abscess: the most common deep neck suppurative complication, with trismus, muffled voice, and uvular deviation; requires drainage plus antibiotics.
- Prognosis
Uncomplicated tonsillitis resolves within about a week with supportive care or a completed antibiotic course; fever and pain typically ease within 24 to 48 hours of starting effective antibiotics for GAS disease.
- Prevention
Test before treating at intermediate risk: a Centor score of 2 to 3 should prompt RADT rather than empiric antibiotics; a score of 0 to 1 needs no testing or antibiotics.
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Related articles
- Streptococcal pharyngitis
Streptococcal pharyngitis is an acute infection of the tonsils and pharynx caused by group A Streptococcus pyogenes, presenting with rapid-onset sore throat, fever, tonsillar exudates, and tender anterior cervical lymphadenopathy without cough; diagnosis relies on the Centor criteria to guide rapid antigen testing, and treatment with penicillin or amoxicillin prevents suppurative complications and acute rheumatic fever.
- Peritonsillar abscess
Peritonsillar abscess is the most common deep-space neck infection, presenting with unilateral sore throat, trismus, a muffled hot potato voice, and uvula deviation away from the affected side, treated with prompt drainage plus antibiotics covering group A streptococcus, Staphylococcus aureus, and oral anaerobes.
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Retropharyngeal abscess is a suppurative infection of the retropharyngeal space that follows antecedent pharyngitis, classically in children 6 months to 6 years, and threatens the airway. Diagnosis begins with lateral neck radiography and is confirmed by contrast CT, and treatment is airway assessment, IV antibiotics against oral flora, and surgical drainage for frank abscess or antibiotic failure.
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Infectious mononucleosis is a systemic illness caused mainly by Epstein-Barr virus, presenting with fever, pharyngitis, and lymphadenopathy, confirmed by heterophile antibody or EBV-specific serology, and managed supportively with contact-sport restriction to prevent splenic rupture.
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Obstructive sleep apnea is repetitive upper airway collapse during sleep, diagnosed by an apnea-hypopnea index of 5 or more per hour with symptoms, or 15 or more per hour regardless of symptoms, and treated first with weight loss plus positive airway pressure.
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Epiglottitis is a rapidly progressive supraglottic infection that can obstruct the airway within hours; the exam is limited to inspection only, and airway control precedes any diagnostic confirmation in an unstable patient.