Do Not Treat Pharyngitis with a Negative Rapid Strep Test
Antibiotics should not be prescribed when the rapid strep test is negative in adults, as this result is sufficient to rule out group A streptococcal pharyngitis and treatment should be limited to symptomatic care only. 1
Age-Specific Management Algorithm
Adults (≥18 years)
- A negative rapid antigen detection test (RADT) alone is sufficient—no backup throat culture is needed 1, 2
- The specificity of RADT is ≥95%, making false positives rare, while the sensitivity is 80-90% 1, 2
- Adults have only 5-10% prevalence of group A streptococcal pharyngitis and extremely low risk of acute rheumatic fever, making the risk-benefit ratio favor withholding antibiotics 1
- Provide symptomatic treatment only: acetaminophen, ibuprofen, NSAIDs, or throat lozenges 1, 2
Children and Adolescents (3-18 years)
- A negative RADT must be confirmed with a backup throat culture before making final treatment decisions 2, 3, 4
- The sensitivity of RADT is only 80-90% in children, missing 10-20% of true infections 2, 5
- Children ages 5-15 have higher prevalence (20-30%) of streptococcal pharyngitis and higher risk of acute rheumatic fever 2, 6
- Withhold antibiotics until culture results are available (18-24 hours) 2, 5
- If culture returns positive, antibiotics can be initiated—treatment within 9 days of symptom onset still prevents acute rheumatic fever 2
Children Under 3 Years
Critical Exceptions Requiring Special Consideration
High-Risk Situations for Acute Rheumatic Fever
Even with a negative RADT, consider backup throat culture in these rare circumstances: 1
- Individual history of acute rheumatic fever
- Age 5-25 years with poor social/hygienic conditions or institutional living
- Recent stay in streptococcal-endemic regions (Africa, West Indies)
- History of recurrent group A streptococcal pharyngitis
- Known outbreak of rheumatogenic strains
Severe or Unusual Presentations
Immediately evaluate for life-threatening conditions if the patient presents with: 1
- Difficulty swallowing, drooling, or neck swelling (peritonsillar abscess, parapharyngeal abscess, epiglottitis)
- Severe pharyngitis in adolescents/young adults with persistent symptoms (consider Fusobacterium necrophorum and Lemierre syndrome—10-20% of endemic pharyngitis cases) 1
Common Pitfalls to Avoid
Do Not Treat Based on Clinical Symptoms Alone
- Clinical features alone cannot reliably distinguish streptococcal from viral pharyngitis—even experienced physicians cannot make this diagnosis with certainty 1, 3
- Treating without laboratory confirmation leads to antibiotic overuse—over 60% of adults with sore throat receive unnecessary antibiotics 1, 5
Do Not Test or Treat Asymptomatic Contacts
- Routine testing of asymptomatic household contacts is not recommended 1, 2, 5
- Up to one-third of households include asymptomatic group A streptococcus carriers who do not require treatment 2
- Prophylactic antibiotics for contacts have not been shown to reduce subsequent infection rates 2
Do Not Perform Post-Treatment Testing
Why Antibiotics Are Not Indicated for Negative Tests
Limited Benefit Even in True Streptococcal Infection
- Antibiotics shorten sore throat duration by only 1-2 days 1
- Number needed to treat is 6 at 3 days and 21 at 1 week 1
- Most pharyngitis cases (70-90%) are viral and self-limited, resolving in less than 1 week 1, 2
Prevention of Complications
The primary justification for treating confirmed streptococcal pharyngitis is prevention of: 1
- Acute rheumatic fever (extremely rare in adults in industrialized countries)
- Peritonsillar abscess (occurs in <1% of cases)
- Spread during outbreaks
Antibiotics do not prevent post-streptococcal glomerulonephritis 1
Symptomatic Management Recommendations
Offer all patients with pharyngitis: 1, 2
- Analgesics: aspirin, acetaminophen, or ibuprofen
- Throat lozenges
- Reassurance that symptoms typically resolve in less than 1 week
- Explanation that antibiotics provide minimal benefit and carry risk of adverse effects