Dangers of Not Treating Strep Throat
The primary danger of untreated strep throat is acute rheumatic fever, which can cause permanent heart damage and remains the leading cause of acquired heart disease in children in developing regions, though treatment within 9 days of symptom onset effectively prevents this complication. 1
Major Complications
Acute Rheumatic Fever (ARF)
- ARF is the most critical nonsuppurative complication that antimicrobial treatment is specifically designed to prevent 1
- Can cause rheumatic heart disease with permanent cardiac valve damage 1
- Treatment initiated within 9 days of symptom onset effectively prevents ARF 1
- While uncommon in developed countries, ARF continues to be the leading cause of acquired heart disease in children in India, sub-Saharan Africa, and parts of Australia and New Zealand 1
- Individuals who develop ARF are at very high risk for recurrent attacks with subsequent strep infections, which can worsen existing heart disease 1
Post-Streptococcal Glomerulonephritis (PSGN)
- Antibiotic treatment does NOT prevent post-streptococcal glomerulonephritis, distinguishing it from ARF 1
- Can cause acute kidney injury with features of nephritic syndrome 2
- May rarely progress to chronic kidney disease requiring long-term monitoring 2
- In extremely rare cases, can lead to pulmonary-renal syndrome with diffuse alveolar hemorrhage, which carries high mortality 3
Suppurative Complications
- Peritonsillar abscess 1
- Cervical lymphadenitis 1
- Mastoiditis 1
- Possibly other invasive infections 1
- These local suppurative complications are prevented by appropriate antimicrobial therapy 1
Clinical Course Without Treatment
Natural History
- Group A streptococcal pharyngitis is typically a self-limited disease 1
- Fever and constitutional symptoms usually resolve spontaneously within 3-4 days of onset even without antibiotics 1
- However, this natural resolution does not eliminate the risk of serious complications, particularly ARF 1
Transmission Risk
- Untreated patients remain contagious and can spread GAS to family members, classmates, and other close contacts 1
- Treatment rapidly decreases contagiousness 1
Important Clinical Caveats
Timing Window for Prevention
- The critical window for preventing ARF extends up to 9 days after symptom onset, allowing flexibility in confirming diagnosis before initiating treatment 1
- This means you can safely wait for culture confirmation without increasing ARF risk if treatment begins within this timeframe 1
Diagnostic Confirmation is Essential
- Clinical features alone cannot reliably distinguish strep throat from viral pharyngitis 1, 4
- Laboratory confirmation (rapid antigen test or throat culture) is mandatory before treating 1, 4
- Treating without confirmation leads to unnecessary antibiotic exposure in the majority of patients (only 20-30% of children with pharyngitis have GAS) 1
Risk Varies by Population
- Adults have extremely low risk of ARF even with untreated strep pharyngitis 1
- Children, particularly school-aged children, are at higher risk for complications 1, 4
- Parents of school-age children and those working closely with children have higher rates of GAS pharyngitis 1
Bottom Line for Clinical Practice
The predominant rationale for treating confirmed strep throat is preventing acute rheumatic fever and its potential for permanent cardiac damage, not simply resolving symptoms which typically improve spontaneously 1. Suppurative complications are also prevented by treatment 1. However, proper diagnosis through laboratory testing is essential to avoid unnecessary antibiotic use in the majority of patients who have viral pharyngitis 1.