How should I treat recurrent group A streptococcal pharyngitis?

Management of Recurrent Group A Streptococcal Pharyngitis

Confirm True Recurrence vs. Chronic Carriage

Most patients with multiple episodes of culture-positive pharyngitis are chronic GAS carriers experiencing repeated viral infections, not true recurrent streptococcal infections. 1

• Distinguish carriers from true infections by evaluating the precise nature of symptoms (sudden onset, high fever, severe throat pain without viral features like cough or rhinorrhea), clinical response to antibiotics, and whether GAS is present during asymptomatic intervals. 1
• Chronic carriers have persistence of the same GAS strain over time, are unlikely to spread infection, and have minimal risk for acute rheumatic fever—they generally do not require antimicrobial therapy. 1, 2
• Viral features (cough, rhinorrhea, hoarseness, conjunctivitis) strongly suggest the current episode is viral superimposed on chronic carriage rather than active GAS infection. 2

First-Line Treatment for a Confirmed Recurrent Episode

For a single recurrent episode shortly after completing appropriate therapy, treat with any standard first-line regimen, but strongly consider intramuscular benzathine penicillin G to ensure compliance. 1

• Penicillin V 500 mg orally twice daily for 10 days (adults) or 250 mg twice daily for children <27 kg remains first-line. 1, 2
• Amoxicillin 50 mg/kg once daily (maximum 1000 mg) or 25 mg/kg twice daily (maximum 500 mg per dose) for 10 days is equally effective and preferred in children for better palatability. 2
• Benzathine penicillin G single intramuscular dose (600,000 units for <27 kg; 1.2 million units for ≥27 kg) eliminates adherence concerns and should be strongly considered for recurrent cases. 1, 2
• A full 10-day course is mandatory for oral regimens to achieve maximal pharyngeal eradication and prevent acute rheumatic fever; shortening by even 2–3 days markedly increases treatment failure rates. 1, 2

Alternative Regimens for Multiple Documented Recurrences

When a patient experiences multiple culture-confirmed recurrent episodes despite appropriate treatment, switch to clindamycin or amoxicillin-clavulanate, which demonstrate substantially higher eradication rates than penicillin in chronic carriers. 1, 2

Clindamycin (Preferred for Treatment Failures)

• Adults: 300 mg orally three times daily for 10 days. 2, 3
• Children: 20–30 mg/kg/day divided three times daily (maximum 300 mg per dose) for 10 days. 2, 3
• Clindamycin resistance is only ~1% in the United States and it achieves superior eradication even in chronic carriers who have failed penicillin. 2, 3

Amoxicillin-Clavulanate (Alternative for Recurrent Failures)

• Dosing: 40 mg/kg/day of the amoxicillin component divided three times daily (maximum 2000 mg amoxicillin/day) for 10 days. 2
• Mechanism: Clavulanate inhibits β-lactamases produced by oral flora (S. aureus, H. influenzae, M. catarrhalis, anaerobes) that can shield GAS from penicillin activity. 1, 4, 5

Penicillin V Plus Rifampin (Less Common Alternative)

• Dosing: Penicillin V 50 mg/kg/day divided four times daily (maximum 2000 mg/day) for 10 days, with rifampin 20 mg/kg/day once daily (maximum 600 mg/day) added during the final 4 days. 2

When NOT to Treat: Recognizing Chronic Carriers

Do not prescribe antibiotics for asymptomatic positive cultures or for symptomatic episodes with clear viral features in a known carrier. 1, 2

• Chronic carriers are identified by persistently positive cultures during asymptomatic intervals, lack of robust clinical response to antibiotics, and presence of viral symptoms (cough, rhinorrhea) during "recurrent" episodes. 1
• Carriers do not require treatment unless special circumstances exist: community outbreak of rheumatic fever or invasive GAS, family history of rheumatic fever, or excessive family anxiety. 1, 2
• Up to one-third of household members may be asymptomatic GAS carriers, and prophylactic treatment of contacts does not reduce subsequent infection rates. 2

Testing Strategy for Recurrent Episodes

Confirm each symptomatic episode with RADT or throat culture before prescribing antibiotics; do not treat based on clinical appearance alone. 2

• A positive RADT is sufficient for diagnosis and does not require backup culture (specificity ≥95%). 2
• In children and adolescents, a negative RADT should be followed by throat culture because RADT sensitivity is only 80–90%, missing 10–20% of true infections. 2
• In adults, a negative RADT alone is sufficient to rule out GAS; backup culture is unnecessary given low prevalence (5–10%) and extremely low rheumatic fever risk. 2
• Do not order routine post-treatment cultures for asymptomatic patients who completed therapy; positive results often reflect carrier status rather than treatment failure. 1, 2

Penicillin-Allergic Patients with Recurrent Infections

Non-Anaphylactic (Delayed) Penicillin Allergy

• First-generation cephalosporins (cephalexin 500 mg twice daily for 10 days in adults; 20 mg/kg twice daily in children, maximum 500 mg per dose) are preferred alternatives with only 0.1% cross-reactivity risk. 2, 3

Immediate/Anaphylactic Penicillin Allergy

• Clindamycin (dosing as above) is the preferred choice with ~1% resistance and superior efficacy in chronic carriers. 2, 3
• Azithromycin 500 mg once daily for 5 days (adults) or 12 mg/kg once daily (maximum 500 mg) for 5 days (children) is acceptable, but macrolide resistance is 5–8% in the United States. 2, 3, 6
• Clarithromycin 250 mg twice daily for 10 days (adults) or 7.5 mg/kg twice daily (maximum 250 mg per dose) for 10 days (children) has similar resistance concerns as azithromycin. 2, 3
• Avoid all β-lactams (including cephalosporins) in immediate/anaphylactic reactions due to ~10% cross-reactivity risk. 2, 3

Tonsillectomy Considerations

Routine tonsillectomy is not recommended solely to decrease the frequency of GAS pharyngitis. 2

• Consider tonsillectomy only when meeting strict criteria: 7 episodes in 1 year, 5 episodes in each of the past 2 years, or 3 episodes in each of the past 3 years. 7

Critical Pitfalls to Avoid

• Do not prescribe continuous antimicrobial prophylaxis for preventing recurrent GAS infections; it is not supported by evidence except for preventing acute rheumatic fever recurrences in patients with prior rheumatic fever. 2
• Do not test or treat asymptomatic household contacts; up to one-third are carriers, and prophylaxis does not reduce subsequent infection rates. 1, 2
• Do not shorten antibiotic courses below 10 days (except azithromycin's 5-day regimen) as this dramatically increases treatment failure and rheumatic fever risk. 1, 2
• Do not use macrolides (azithromycin, clarithromycin) for retreatment of multiple recurrences due to 5–8% resistance rates; clindamycin or amoxicillin-clavulanate are more reliable. 2, 3
• Do not prescribe antibiotics for episodes with clear viral features (cough, rhinorrhea, hoarseness) in a known carrier; these are viral infections superimposed on carriage. 1, 2

Adjunctive Symptomatic Management

• Acetaminophen or ibuprofen for moderate-to-severe sore throat, fever, or systemic discomfort. 2, 8
• Avoid aspirin in children due to Reye syndrome risk. 2, 8
• Corticosteroids are not recommended as adjunctive therapy for streptococcal pharyngitis. 2, 8