What is the recommended treatment for a patient with a group G strep throat culture?

Treatment of Group G Streptococcal Pharyngitis

Group G streptococcus pharyngitis should be treated with the same antibiotic regimens used for Group A streptococcal pharyngitis, with penicillin or amoxicillin as first-line therapy for 10 days.

First-Line Treatment Options

The treatment approach mirrors that of Group A streptococcal (GAS) pharyngitis, as Group G streptococcus is also a beta-hemolytic streptococcus with similar clinical significance:

Oral Penicillin Regimens

• Penicillin V: 250 mg twice or three times daily for children, or 250 mg three to four times daily (or 500 mg twice daily) for adolescents and adults, administered for 10 days 1
• Amoxicillin: 50 mg/kg once daily (maximum 1000 mg) for 10 days, often preferred in young children due to better palatability and simplified once-daily dosing 1, 2
• The full 10-day course is essential for bacterial eradication and prevention of complications 1

Intramuscular Option

• Benzathine penicillin G: Single dose of 600,000 units for patients <27 kg or 1.2 million units for patients ≥27 kg 3, 1
• This route is preferred when adherence to oral therapy is questionable, as it ensures complete treatment and eliminates compliance issues 3, 4

Treatment for Penicillin-Allergic Patients

Non-Anaphylactic Allergy

• First-generation cephalosporins (e.g., cephalexin 20 mg/kg per dose twice daily, maximum 500 mg per dose, or cefadroxil 30 mg/kg once daily, maximum 1 g) for 10 days 1, 5

Anaphylactic Allergy

• Clindamycin: 7 mg/kg per dose three times daily (maximum 300 mg per dose) for 10 days 1, 5
• Clarithromycin: 7.5 mg/kg per dose twice daily (maximum 250 mg per dose) for 10 days 1, 5
• Azithromycin: 12 mg/kg once daily (maximum 500 mg) for 5 days 5
• Note that macrolide resistance varies geographically and should be considered when selecting treatment 5

Management of Recurrent Episodes

If a patient experiences recurrent positive cultures shortly after completing therapy:

• First recurrence: Retreat with any appropriate first-line agent from above 3
• If compliance is questionable: Use intramuscular benzathine penicillin G 3
• Multiple recurrences: Consider whether the patient is a chronic carrier experiencing viral infections rather than true recurrent bacterial infections 3, 1

For Documented Multiple Recurrences

• Clindamycin: 20-30 mg/kg/day for children or 600 mg/day in 2-4 divided doses for adults, for 10 days 3
• Amoxicillin-clavulanate: 40 mg/kg/day in 3 divided doses (maximum 750 mg amoxicillin per day) for 10 days 3
• Benzathine penicillin G with rifampin: Single dose benzathine penicillin G plus rifampin 20 mg/kg/day in 2 doses (maximum 600 mg/day) for 4 days 3

Symptomatic Management

• Acetaminophen or NSAIDs for moderate to severe symptoms or fever control 1, 6
• Avoid aspirin in children due to risk of Reye syndrome 1, 6
• Corticosteroids are not recommended for routine use 1, 6
• Warm salt water gargles may provide symptomatic relief 6

Important Clinical Considerations

Diagnostic Confirmation

While the guidelines focus on Group A streptococcus, Group G streptococcus is also a beta-hemolytic streptococcus that can cause pharyngitis and should be treated when identified on culture 3. Rapid antigen detection tests are designed for Group A streptococcus and will not detect Group G, so throat culture is the diagnostic method 3.

Common Pitfalls to Avoid

• Incomplete treatment courses: Failure to complete the full 10-day course of penicillin or amoxicillin can lead to treatment failure 1
• Unnecessary follow-up cultures: Routine post-treatment cultures are not recommended for asymptomatic patients who completed therapy 3
• Overuse of broad-spectrum antibiotics: Penicillin remains preferred due to narrow spectrum, proven efficacy, safety, and low cost 3, 1