Streptococcal pharyngitis

Background[1]

  • Peak in 5-15yr old
  • Rare in <2yr of age
  • Accounts for only 15-30% of pharyngitis
  • Caused by S. pyogenes (Group A strep)
  • Peak season is late winter / early spring
  • Transmission is respiratory secretions
  • Incubation period is 24-72 hours
  • Antibiotics shorten symptoms by 16 hours

Clinical Features

culture positive strep pharyngitis with typical tonsillar exudate

Should NOT have a rash; if have scarlatiniform rash consider scarlet fever

Modified Centor Criteria[2]

One point is given for each of the criteria:[2]

  1. Absence of a cough
  2. Swollen and tender cervical lymph nodes
  3. Temperature >38.0 °C (100.4 °F)
  4. Tonsillar exudate or swelling
  5. Age less than 15^
    • Subtract a point if age >44
Modified Centor score
Points Probability of Streptococcal pharyngitis
1 or fewer <10%
2 11–17%
3 28–35%
4 or 5 52%

Differential Diagnosis

Acute Sore Throat

Bacterial infections

Viral infections

Noninfectious

Other

Oral rashes and lesions

Evaluation

Rapid Antigen Detection Test Algorithm for Acute Pharyngitis[4]

Category Testing and Treatment
Clinical features strongly suggesting viral etiology (eg. cough, rhinorrhea, hoarseness, oral ulcers)
  • None
<3 years old
  • None
    • Unless they have a special risk factor (e.g. older sibling with GAS infection)
CENTOR = 1
  • None
None of the above with CENTOR ≥2
  • Send rapid antigen detection test
    • Positive = treat
    • Negative
      • Children and adolescents
        • Send back up throat culture (treat later, if positive)
      • Adults
        • None (no need for back up throat culture)

Diagnostic testing or empiric treatment of asymptomatic household contacts of patients with acute streptococcal pharyngitis is not routinely recommended

Management

Antibiotics

Treatment can be delayed for up to 9 days and still prevent major sequelae

Penicillin Options:[5]

  • Penicillin V 250mg PO BID x 10d (child) or 500mg BID x 10d (adolescent or adult)
  • Bicillin L-A <27 kg: 0.6 million units; ≥27 kg: 1.2 million units IM x 1

Penicillin allergic (mild):[6]

  • Cefuroxime 10mg/kg PO QID x 10d (child) or 250mg PO BID x 4d

Penicillin allergic (anaphylaxis):[7]

  • Clindamycin 7.5mg/kg PO QID x 10d (child) or 450mg PO TID x 10d OR
  • Azithromycin 12mg/kg QD (child) or 500mg on day 1; then 250mg on days 2-5

Steroids

Disposition

  • Discharge

Complications

See Also

References

  1. Choby BA. Amer Fam Phys. 2009, 79(5), 383-90.
  2. 2.0 2.1 Choby BA (March 2009). "Diagnosis and treatment of streptococcal pharyngitis". Am Fam Physician 79 (5): 383–90. PMID 19275067.
  3. Melio, Frantz, and Laurel Berge. “Upper Respiratory Tract Infection.” In Rosen’s Emergency Medicine., 8th ed. Vol. 1, n.d.
  4. Shulman, et al. Clinical Practice Guideline for the Diagnosis and Management of Group A Streptococcal Pharyngitis: 2012 Update by the Infectious Diseases Society of America. Clinical Infectious Diseases 2012;55(10):1279–82
  5. Shulman, et al. Clinical Practice Guideline for the Diagnosis and Management of Group A Streptococcal Pharyngitis: 2012 Update by the Infectious Diseases Society of America. Clinical Infectious Diseases 2012;55(10):1279–82
  6. Shulman, et al. Clinical Practice Guideline for the Diagnosis and Management of Group A Streptococcal Pharyngitis: 2012 Update by the Infectious Diseases Society of America. Clinical Infectious Diseases 2012;55(10):1279–82
  7. Shulman, et al. Clinical Practice Guideline for the Diagnosis and Management of Group A Streptococcal Pharyngitis: 2012 Update by the Infectious Diseases Society of America. Clinical Infectious Diseases 2012;55(10):1279–82
  8. EBQ:TOAST Trial