What is the management and treatment for a patient with a sore throat, low-grade subjective fevers, and suspected streptococcal (strep) pharyngitis?

Management of Suspected Streptococcal Pharyngitis

For a patient with sore throat, low-grade fevers, and concern for strep, first assess the Centor criteria (fever, tonsillar exudates, tender anterior cervical lymphadenopathy, absence of cough), then test with rapid antigen detection test (RADT) or throat culture, and treat with penicillin V or amoxicillin for 10 days only if testing confirms Group A streptococcal infection or if the patient has 3-4 Centor criteria. 1, 2

Initial Assessment and Testing Strategy

• Calculate the Centor criteria to determine likelihood of bacterial pharyngitis: sudden onset of sore throat, fever, tonsillar exudates, tender anterior cervical lymphadenopathy, and absence of cough 1, 2

• Do NOT treat with antibiotics if the patient has 0-2 Centor criteria, as these presentations are likely viral and antibiotics provide no benefit 1

• For patients with 3-4 Centor criteria, perform RADT or throat culture before initiating treatment 1, 2

  • A positive RADT is diagnostic and requires no backup culture in adults 1, 2
  • In children and adolescents, perform backup throat culture if RADT is negative 2

• Clinical features suggesting viral (not bacterial) pharyngitis include cough, rhinorrhea, hoarseness, oral ulcers, or conjunctivitis—do not test or treat these patients with antibiotics 1, 3

First-Line Antibiotic Treatment (When Indicated)

Penicillin V remains the treatment of choice due to proven efficacy, safety, narrow spectrum, low cost, and zero documented resistance over five decades 1

Dosing for Non-Penicillin-Allergic Patients:

• Penicillin V (oral):

  • Children: 250 mg twice or three times daily for 10 days 1, 2
  • Adolescents/adults: 250 mg four times daily OR 500 mg twice daily for 10 days 1, 2

• Amoxicillin (oral) is an acceptable alternative, particularly for young children due to better taste:

  • 50 mg/kg once daily (maximum 1000 mg) OR 25 mg/kg twice daily (maximum 500 mg per dose) for 10 days 1, 2

• Benzathine penicillin G (intramuscular) for patients unlikely to complete oral therapy:

  • 600,000 units for patients <27 kg (60 lbs) 2
  • 1,200,000 units for patients ≥27 kg 2

Critical Treatment Principles:

• The full 10-day course is mandatory to ensure complete bacterial eradication and prevent rheumatic fever 1, 4

• Shorter courses of penicillin (3-5 days) are less effective for clinical cure (OR 0.43) and bacteriological eradication (OR 0.34) compared to 10-day courses 5

• Therapy can be safely delayed up to 9 days after symptom onset and still prevent rheumatic fever, so immediate treatment is not required while awaiting test results 1

Treatment for Penicillin-Allergic Patients

• First-generation cephalosporins (e.g., cephalexin 20 mg/kg twice daily, maximum 500 mg per dose) for 10 days in patients without anaphylactic penicillin allergy 1, 2, 6

• For anaphylactic penicillin allergy, use:

  • Clindamycin 7 mg/kg three times daily (maximum 300 mg per dose) for 10 days 1, 6, OR
  • Clarithromycin 7.5 mg/kg twice daily (maximum 250 mg per dose) for 10 days 1, 6, OR
  • Azithromycin 12 mg/kg once daily (maximum 500 mg) for 5 days 1, 6

• Important caveat: Macrolide resistance varies geographically, and azithromycin lacks data for preventing rheumatic fever 7, 6

Symptomatic Management

• Ibuprofen or acetaminophen are recommended for relief of throat pain and fever 1, 2, 6

• Avoid aspirin in children due to risk of Reye syndrome 2, 6

• Corticosteroids are NOT routinely recommended but can be considered in adults with severe presentations (3-4 Centor criteria) when used with antibiotics 1

Expected Clinical Course and Benefits

• Antibiotics reduce symptoms modestly: throat soreness improves by approximately 1-2 days, with maximal effect at day 3 1, 8

• At day 3, antibiotics reduce sore throat symptoms (RR 0.70), but 82% of untreated patients are symptom-free by one week regardless of treatment 8

• The number needed to treat (NNT) to prevent one sore throat at day 3 is approximately 5-6 patients; at one week it increases to 14-18 patients 8, 9

• Benefits must be weighed against side effects, antimicrobial resistance, medicalization, and costs 1

Prevention of Complications

Suppurative Complications:

• Antibiotics reduce acute otitis media to one-quarter of placebo rates (OR 0.21) 8
• Quinsy (peritonsillar abscess) is reduced (OR 0.16) 8
• Acute sinusitis shows no significant reduction (OR 0.46) 8

Non-Suppurative Complications:

• Acute rheumatic fever is reduced to less than one-third with antibiotics (OR 0.36), though overall prevalence is now very low in developed countries 8, 9
• Acute glomerulonephritis data are insufficient to confirm protective effect 1, 8

Common Pitfalls to Avoid

• Do NOT treat asymptomatic household contacts routinely—this is not recommended and exposes them to unnecessary antibiotic risks 1

• Do NOT perform routine follow-up throat cultures on asymptomatic patients who completed adequate therapy 1, 3

• Do NOT use antibiotics to prevent suppurative complications in low-risk patients (those without prior rheumatic fever history) 1

• Avoid treating viral pharyngitis—up to 20% of school-aged children are asymptomatic Group A strep carriers during winter/spring, so positive tests may not indicate true infection 1, 3

• Do NOT use amoxicillin in older children/adolescents with possible mononucleosis, as it causes severe rash in Epstein-Barr virus infection 1

• Delayed prescribing (providing prescription but instructing patient to wait 48 hours before filling) is a valid strategy that reduces antibiotic use without increasing complications 1