What are the therapeutic guidelines for treating acute tonsillitis in an Australian patient?

Therapeutic Guidelines for Acute Tonsillitis in Australia

Diagnostic Approach

Before initiating any treatment, confirm Group A Streptococcus (GAS) infection using rapid antigen detection testing (RADT) and/or throat culture, as most cases are viral and do not require antibiotics. 1, 2

• Use the modified Centor/McIsaac scoring system (≥3 points) to estimate bacterial probability, considering age and absence of respiratory symptoms 3, 4
• Bacterial tonsillitis presents with sudden onset sore throat, fever >38°C, tonsillar exudates, tender anterior cervical lymphadenopathy, and absence of cough 1, 2
• Viral tonsillitis typically lacks high fever, tonsillar exudate, and cervical lymphadenopathy 2
• Do not rely on clinical features alone—exudative tonsillitis in children is not diagnostic of streptococcal etiology 4

First-Line Medical Treatment

For confirmed GAS tonsillitis, prescribe penicillin V for 10 days as the gold standard treatment, or amoxicillin for 10 days as an acceptable alternative. 1, 2, 5

Antibiotic Regimens:

• Penicillin V: Standard first-line therapy for 10 days 1, 2
• Amoxicillin: 500 mg every 12 hours or 250 mg every 8 hours for mild/moderate infections; 875 mg every 12 hours or 500 mg every 8 hours for severe infections in adults and children >40 kg 5
• Pediatric dosing (3 months to <40 kg): 25 mg/kg/day divided every 12 hours or 20 mg/kg/day divided every 8 hours for mild/moderate; 45 mg/kg/day divided every 12 hours or 40 mg/kg/day divided every 8 hours for severe infections 5

Penicillin-Allergic Patients:

• Non-anaphylactic allergy: First-generation cephalosporins (e.g., cephalexin) 2, 4
• Anaphylactic allergy: Clindamycin, azithromycin, or clarithromycin 2, 6
• Note: Macrolides are not first-line treatment and should be reserved for true penicillin allergy 4

Critical Treatment Duration:

The full 10-day antibiotic course is mandatory to maximize bacterial eradication and prevent rheumatic fever and glomerulonephritis, even if symptoms resolve earlier. 1, 2, 5

Symptomatic Management

Provide ibuprofen and/or paracetamol (acetaminophen) as first-line analgesia for pain and fever control. 3, 1, 7

• NSAIDs (ibuprofen or flurbiprofen) are strongly recommended as adjunctive therapy for moderate to severe symptoms 7
• Multiple randomized controlled trials demonstrate significant pain and fever reduction with NSAIDs 7
• A single dose of dexamethasone may provide additional pain relief in severe cases, particularly when combined with antibiotics 3, 7
• No increased bleeding risk has been demonstrated with NSAIDs in tonsillar procedures 7

Supportive Care:

• Ensure adequate hydration 1
• Minimize fasting time to 4 hours for solids and 2 hours for liquids to improve postoperative outcomes if surgery is considered 3
• Educate caregivers about managing and reassessing pain 3, 1

Delayed Antibiotic Strategy

In ambiguous cases with Centor/McIsaac score <3 and negative or unavailable RADT, use a "delayed antibiotic prescription" strategy with 2-3 day monitoring. 4

• This approach is highly effective in reducing unnecessary antibiotic use 4
• Instruct patients to fill prescription only if symptoms worsen or fail to improve within 48-72 hours 4

Management of Recurrent Tonsillitis

Recommend watchful waiting if episodes are fewer than 7 in the past year, fewer than 5 per year for 2 consecutive years, or fewer than 3 per year for 3 consecutive years. 1, 2, 7

Tonsillectomy Indications (Paradise Criteria):

Consider tonsillectomy when episodes meet ALL of the following 1, 2, 7, 8:

• Frequency: ≥7 well-documented episodes in the preceding year, OR ≥5 episodes per year for 2 consecutive years, OR ≥3 episodes per year for 3 consecutive years
• Documentation: Each episode must be documented in the medical record with temperature >38.3°C, cervical adenopathy, tonsillar exudate, OR positive test for GAS 1, 2
• Adequate treatment: Episodes must have been adequately treated with appropriate antibiotics 1, 8

Evidence for Watchful Waiting:

• Control groups in randomized trials show spontaneous reduction to only 0.3-1.17 episodes per year without surgery 1
• Tonsillectomy is highly effective when Paradise criteria are met, but should not be performed without meeting appropriate frequency and documentation criteria 2, 7, 8

Post-Tonsillectomy Pain Management

For patients undergoing tonsillectomy, use combinations of paracetamol and NSAIDs pre-operatively or intra-operatively, and continue postoperatively. 3

• A single intra-operative dose of IV dexamethasone is also recommended 3
• Coblation techniques have slightly less postoperative pain during the first day compared with cold dissection and electrocautery 3
• Do not restrict postoperative diet to liquids or cold foods, as this does not improve pain, nausea, or bleeding outcomes 3

Critical Pitfalls to Avoid

Never initiate antibiotics without confirming GAS infection through testing, as this drives antibiotic resistance and is ineffective for viral tonsillitis. 1, 2, 4

• Do not use broad-spectrum antibiotics when narrow-spectrum penicillins are effective for confirmed GAS 1, 2
• Do not prescribe antibiotic courses shorter than 10 days for GAS tonsillitis, as this increases risk of treatment failure and complications 1, 2, 7
• Do not perform tonsillectomy solely to reduce frequency of GAS pharyngitis in chronic carriers 7
• Do not routinely perform follow-up throat cultures for asymptomatic patients who completed appropriate antibiotic therapy 2, 7
• Prevention of purulent complications (paratonsillitis, retropharyngeal abscess, acute otitis media) is not a specific indication for antibiotics in most patients with acute tonsillitis 4

Follow-Up Recommendations

If symptoms persist despite appropriate antibiotic therapy, consider medication non-compliance, chronic GAS carriage with intercurrent viral infections, or need for alternative antibiotics. 2, 7

• Do not perform routine follow-up throat cultures in asymptomatic patients 2, 7
• Distinguish between true recurrent infections and chronic GAS carrier state with intercurrent viral infections 7
• GAS carriers generally do not require antimicrobial therapy and are unlikely to spread infection or develop complications 7