OnExam

The Strep Throat Score helps avoid overdiagnosis of streptococcal pharyngitis and thus reduces the misuse of antibiotics. When used to evaluate whether or not group A strep (GAS) is the etiology of pharyngitis, it has a sensitivity of 83.1% and a specificity 96.9%.

Calculation

  1. Tonsillar swelling or exudate (1 pt)
  2. Tender anterior cervical nodes (1 pt)
  3. Absence of cough (1 pt)
  4. Temperature >38°C (1 pt)
  5. Age 3-14 (1 pt); Age 15-44 (0 pts); Age ≥45 yrs (-1 pt)

Interpretation of Total Score

  • 1 pt - No culture or antibiotic required (2-6% likelihood of GAS)
  • 2-3 pts - Culture all and treat only if culture positive (10-28% likelihood)
  • 4 pts - Culture and treat with penicillin (or any sensitive antibiotic if the patient is allergic) based on clinical grounds (38-63% likelihood)
    • Note importance of clinical treatment for prevention of complications such as poststreptococcal glomerulonephritis

References

  1. McIsaac WJ, White D, Tannenbaum D, Low DE (1998). A clinical score to reduce unnecessary antibiotic use in patients with sore throat. CMAJ. 158(1):79.