Should a 22-year-old patient with a throat culture positive for Group G streptococcus be treated?

Treatment of Group G Streptococcus in a 22-Year-Old Patient

Group G streptococcus isolated from a throat culture in a 22-year-old patient should not be routinely treated with antibiotics, as there is no strong evidence supporting treatment of non-Group A streptococcal pharyngitis to prevent complications such as rheumatic fever. 1, 2

Understanding Group G Streptococcus vs. Group A Streptococcus

• The Infectious Diseases Society of America (IDSA) guidelines primarily focus on Group A Streptococcus (GAS) pharyngitis, as this is the organism associated with complications like acute rheumatic fever 1
• Group G streptococci (particularly Streptococcus dysgalactiae subsp. equisimilis) are emerging human pathogens that can cause throat infections but have different clinical implications than Group A streptococci 2
• The risk of acute rheumatic fever, which is the primary reason for treating streptococcal pharyngitis, is extremely low in adults, even with untreated Group A streptococcal pharyngitis 1

Clinical Decision Making Algorithm

1. Assess clinical presentation:

   • If the patient has severe symptoms (high fever, significant tonsillar exudate, tender cervical lymphadenopathy) 3
   • If the patient has risk factors (immunocompromised, severe underlying medical conditions) 2
   • If there are signs of invasive infection or complications 2

2. Consider treatment only if:

   • The patient is severely symptomatic 3
   • The patient has specific risk factors for complications 2
   • There is evidence of invasive infection 2

3. If treatment is deemed necessary:

   • Penicillin remains the drug of choice for streptococcal infections 4, 5
   • Amoxicillin is equally effective and may be more palatable 4, 3
   • For penicillin-allergic patients, erythromycin or first-generation cephalosporins are options 1

Important Considerations

• IDSA guidelines specifically recommend treatment for Group A streptococcal pharyngitis, not Group G 1
• The primary rationale for treating streptococcal pharyngitis is to prevent acute rheumatic fever, which is not typically associated with Group G streptococcus 1, 2
• In adults, the risk of acute rheumatic fever is extremely low, even with untreated Group A streptococcal pharyngitis 1
• Unnecessary antibiotic use contributes to antimicrobial resistance and exposes patients to potential adverse effects 1

Special Circumstances

• If the patient is immunocompromised or has severe underlying medical conditions, treatment might be warranted as Group G streptococci can cause invasive infections in these populations 2
• If the patient has severe symptoms that significantly impact quality of life, symptomatic treatment with analgesics/antipyretics may be more appropriate than antibiotics 1
• If treatment is deemed necessary, penicillin for 10 days would be the standard approach, similar to treatment for Group A streptococcus 4, 5

Common Pitfalls to Avoid

• Treating all positive throat cultures regardless of the streptococcal group 1
• Failing to distinguish between true infection and colonization/carrier state 1
• Overestimating the risk of complications from non-Group A streptococcal pharyngitis 1, 2
• Using broad-spectrum antibiotics unnecessarily when narrower spectrum options would be more appropriate if treatment is needed 1