What is the most appropriate next step in management for a 10-year-old boy with fever, headache, sore throat, enlarged tonsils with exudate, pharyngeal petechiae, and cervical lymphadenopathy, who has a negative rapid strep test (Rapid Streptococcal Antigen Test) and normal vital signs except for hyperthermia (Temperature: 39°C) and normal blood pressure (Hypertension: 100/65 mmHg)?

Management of Pharyngitis with Negative Rapid Strep Test in a 10-Year-Old

The most appropriate next step is to obtain a confirmatory throat culture before making any treatment decisions, as negative rapid strep tests in children must be backed up by culture due to the 10-20% false-negative rate. 1

Why Throat Culture is Mandatory in This Case

• In children and adolescents, a negative RADT must always be confirmed with throat culture before withholding antibiotics, as the sensitivity of rapid tests is only 80-90%, meaning they miss 10-20% of true streptococcal infections 1

• This patient has multiple high-risk features that increase the likelihood of Group A Streptococcal (GAS) pharyngitis despite the negative rapid test 1:

  • Age 10 years (peak incidence is 5-15 years)
  • Tonsillar exudates
  • Pharyngeal petechiae
  • Anterior and posterior cervical lymphadenopathy
  • Fever (39°C)
  • Absence of viral features (no cough, rhinorrhea, or conjunctivitis mentioned)

• The clinical presentation strongly suggests bacterial pharyngitis, making a false-negative rapid test more likely than a true viral infection 1, 2

Immediate Management While Awaiting Culture

• Provide symptomatic relief with acetaminophen or ibuprofen for fever and pain control 1, 3
• Avoid aspirin in children due to risk of Reye syndrome 1
• Withhold antibiotics until culture results are available 1, 3
• Reassure that treatment can be safely delayed - initiating antibiotics within 9 days of symptom onset still effectively prevents acute rheumatic fever 3

Critical Diagnostic Considerations

This presentation warrants special attention for alternative diagnoses:

• Infectious mononucleosis (Epstein-Barr virus) commonly presents with severe pharyngitis, tonsillar exudates, posterior cervical lymphadenopathy, and can have pharyngeal petechiae 1, 3
• Consider monospot or EBV serology if the throat culture returns negative, given the prominent posterior cervical adenopathy 1
• The combination of exudates, petechiae, and extensive lymphadenopathy (both anterior AND posterior chains) is more typical of mononucleosis than uncomplicated streptococcal pharyngitis 1

What NOT to Do

• Do not start empiric antibiotics based on clinical appearance alone - even with classic features, only 35-50% of such patients have confirmed GAS pharyngitis 1
• Do not test or treat household contacts - this is not recommended even with confirmed streptococcal infection 1, 3
• Do not rely on the negative rapid test alone in children - this is the single most common error in pediatric pharyngitis management 1

Follow-Up Based on Culture Results

If throat culture is positive for GAS:

• Initiate penicillin V (250 mg twice or three times daily) or amoxicillin (25 mg/kg twice daily, max 500 mg/dose) for 10 days 1
• Benzathine penicillin G 1,200,000 units IM as single dose is an alternative if compliance is a concern 1

If throat culture is negative:

• Antibiotics should be withheld or discontinued 3
• Continue symptomatic management only 1, 3
• Consider alternative diagnoses, particularly infectious mononucleosis given the clinical presentation 1

Common Pitfall to Avoid

The most critical error would be treating based on clinical features alone without microbiological confirmation - this leads to unnecessary antibiotic exposure in 50-65% of cases, contributing to antimicrobial resistance and adverse drug effects 1, 2. The proper sequence is: negative RADT → throat culture → treatment decision based on culture results 1.