What are the guidelines for treating acute tonsillitis?

Treatment Guidelines for Acute Tonsillitis

The cornerstone of tonsillitis management is distinguishing viral from bacterial etiology through rapid antigen detection testing (RADT) or throat culture for Group A Streptococcus (GAS), with antibiotics reserved exclusively for confirmed bacterial cases. 1, 2

Diagnostic Approach

Testing is mandatory before prescribing antibiotics to avoid unnecessary antibiotic exposure and resistance development. 3, 2

When to Test for GAS:

• Perform RADT or throat culture in patients presenting with sudden onset sore throat, fever >38°C (101.5°F), tonsillar exudates, tender anterior cervical lymphadenopathy, and absence of cough. 1, 2
• Do NOT test patients with clear viral features including cough, rhinorrhea, hoarseness, or conjunctivitis—these patients require symptomatic treatment only. 2
• Modified Centor/McIsaac score ≥3 serves as a reasonable threshold for testing, though testing should still be performed rather than treating empirically. 4

Critical Diagnostic Pitfalls to Avoid:

• Never assume exudates equal bacterial infection—viral infections frequently produce exudates. 2
• Never prescribe antibiotics based on clinical impression alone without microbiological confirmation. 2
• Do NOT use ASO titers to guide acute treatment decisions—they reflect past immunologic response, not current infection. 1

Antibiotic Treatment for Confirmed GAS Tonsillitis

First-Line Treatment:

Penicillin V 500 mg orally twice daily for 10 days is the gold standard due to proven efficacy, narrow spectrum, safety, low cost, and zero documented GAS resistance. 1, 3, 2

Alternative penicillin dosing:

• Penicillin V 250 mg three or four times daily for 10 days 3
• Amoxicillin 500 mg twice daily for 10 days (equally effective with better palatability and adherence) 1, 3, 5

For Penicillin-Allergic Patients:

• Non-anaphylactic allergy: First-generation cephalosporins (cefalexin, cefadroxil) for 10 days 1
• Anaphylactic allergy: Clindamycin, azithromycin (5 days), or clarithromycin 1
• Never use cephalosporins in patients with anaphylactic penicillin reactions due to cross-reactivity risk. 3

Duration of Treatment:

The full 10-day course is mandatory to maximize bacterial eradication and prevent rheumatic fever—this is non-negotiable. 6, 1, 3, 5

• Short courses (5 days) of standard-dose penicillin are less effective for GAS eradication and should be avoided. 1
• The only exception: Azithromycin 5-day regimen or high-dose penicillin (four times daily) for 5 days, though the latter is not standard practice. 1, 3

Post-Treatment Follow-Up:

Do NOT obtain routine follow-up throat cultures for asymptomatic patients who completed appropriate antibiotic therapy. 1

Symptomatic Treatment

All patients should receive symptomatic relief regardless of whether antibiotics are prescribed. 1

Pain and Fever Management:

• NSAIDs (ibuprofen) or acetaminophen for pain and fever control 1, 3
• Throat lozenges containing topical anesthetics (benzocaine, lidocaine) for temporary relief 3
• Warm salt water gargles for patients old enough to perform them 1, 3
• Adequate hydration and supportive measures 3

Topical Therapy:

Benzalkonium chloride + tyrothricin + benzocaine may provide additional benefit as etiopathogenetic treatment for viral tonsillitis or as adjunct for bacterial cases. 4

Management of Recurrent Tonsillitis

For Early Recurrence (Within 2 Weeks of Completing Therapy):

Consider treatment failure, chronic carriage with intercurrent viral infection, or new GAS infection. 1

Alternative antibiotic regimens for documented recurrent GAS:

• Clindamycin 20-30 mg/kg/day in 3 doses (maximum 300 mg/dose) for 10 days 1
• Amoxicillin-clavulanate 40 mg amoxicillin/kg/day in 3 doses (maximum 2000 mg amoxicillin/day) for 10 days 1
• Penicillin V with rifampin: Penicillin V 50 mg/kg/day in 4 doses for 10 days plus rifampin 20 mg/kg/day in 1 dose for the last 4 days 1

Chronic Carriers:

Up to 20% of asymptomatic school-age children may be GAS carriers during winter and spring, and they may experience viral pharyngitis episodes that test positive for GAS. 1

• Chronic carriers are unlikely to spread GAS to contacts and are at very low risk for suppurative or nonsuppurative complications. 1
• Consider chronic carriage in patients with recurrent positive tests rather than repeated bacterial infections. 1

Tonsillectomy Indications:

Watchful waiting is strongly recommended if episodes are <7 in the past year, <5 per year for 2 years, or <3 per year for 3 years. 1, 7

Consider tonsillectomy when meeting Paradise criteria: ≥7 documented episodes in the past year, ≥5 per year for 2 years, or ≥3 per year for 3 years. 1

• Each documented episode must include sore throat plus at least one of: temperature ≥38.3°C, cervical adenopathy, tonsillar exudate, or positive GAS test. 1
• Tonsillectomy is NOT recommended solely to reduce frequency of GAS pharyngitis. 1

Expected Clinical Course

Antibiotics shorten symptom duration by only 1-2 days in confirmed streptococcal infection, with a number needed to treat of 6 to reduce symptoms after 3 days. 2

Clinical improvement should occur within 24-48 hours of initiating therapy, with resolution of fever within 48 hours in uncomplicated cases. 6

Key Clinical Pearls

• Most tonsillitis (70-95%) is viral and self-limiting within 7 days—antibiotics are not indicated. 7, 3
• Prevention of purulent complications (peritonsillar abscess, acute otitis media) is NOT a specific indication for antibiotics in most patients. 4
• "Delayed antibiotic prescription" strategy with 2-3 day monitoring is appropriate and highly effective in doubtful cases. 4
• Macrolides are NOT first-line treatment for acute tonsillitis. 4