What is the assessment, differential diagnosis (DDX), and management for a 7-year-old child presenting with enlarged red tonsils and tonsillar exudate?

Assessment and Management of 7-Year-Old with Enlarged Red Tonsils and White Exudate

Primary Assessment: Group A Streptococcal Pharyngitis

This presentation requires immediate risk stratification using clinical criteria and rapid diagnostic testing to determine if bacterial infection (specifically Group A β-hemolytic streptococcus) is present, as this is the only common form of acute pharyngitis requiring antibiotic therapy. 1

Clinical Evaluation

The key clinical features to document include:

• Temperature: Fever ≥38.3°C (101°F) 1, 2
• Tonsillar findings: Erythema and white exudate (already present) 1
• Cervical lymphadenopathy: Tender, enlarged anterior cervical nodes 1, 2
• Absence of viral features: No cough, conjunctivitis, hoarseness, coryza, or diarrhea 1

At age 7, this child falls within the peak age range (5-15 years) where Group A streptococcus causes 15-30% of acute pharyngitis cases. 3, 4

Risk Stratification Using Centor/McIsaac Criteria

Apply the modified McIsaac score (1 point each):

• Age 3-14 years: 1 point 3
• Fever ≥38.3°C: 1 point 3
• Tonsillar swelling or exudate: 1 point 3
• Tender anterior cervical lymphadenopathy: 1 point 3
• Absence of cough: 1 point 3

With a score of 2-3 or higher, proceed immediately to rapid antigen detection test (RADT). 2, 3 Do not treat based on clinical appearance alone—even patients with all clinical features have confirmed streptococcal pharyngitis only 35-50% of the time. 3

Differential Diagnosis

Most Likely Causes:

1. Group A β-hemolytic Streptococcus (Streptococcus pyogenes): 15-30% probability in this age group with these findings 4, 5

2. Viral pharyngitis: 70-95% of tonsillitis cases overall, including:

   • Epstein-Barr virus (infectious mononucleosis)
   • Adenovirus
   • Influenza virus
   • Other respiratory viruses 1, 4

3. Other bacterial causes (uncommon):

   • Groups C and G β-hemolytic streptococci
   • Mycoplasma pneumoniae
   • Chlamydia pneumoniae 1

Diagnostic Testing

Perform RADT immediately in the office. 2, 3 RADT has high specificity (≥95%) and negative predictive value (93-97%). 2

• If RADT positive: Treat with antibiotics 2
• If RADT negative in a child: Obtain backup throat culture, as RADT sensitivity is lower in pediatrics 3
• Throat culture remains the gold standard but requires 24-48 hours for results 5

Management

If Group A Streptococcus Confirmed:

First-line antibiotic therapy: Penicillin V 250 mg orally twice or three times daily for 10 days. 2, 3, 6 The full 10-day course is essential to optimize bacterial eradication and prevent rheumatic fever. 6

Alternative antibiotics for penicillin allergy:

• First-generation cephalosporins
• Clindamycin
• Clarithromycin
• Azithromycin 3

Counsel families that antibiotics provide modest symptom relief, shortening sore throat duration by only 1-2 days (number needed to treat = 6 at 3 days, 21 at 1 week), but are critical for preventing acute rheumatic fever, suppurative complications, and transmission. 2, 3

Symptomatic Management (Regardless of Etiology):

Prescribe ibuprofen or acetaminophen for pain relief. 2 These are evidence-based symptomatic treatments that should be provided to all patients. 2

Throat lozenges may provide additional relief. 2

If Viral Etiology (Negative Testing):

Treat symptomatically with analgesics only—no antibiotics. 3 Counsel that typical sore throat duration is less than 1 week, with most cases resolving within 7 days. 2

Critical Pitfalls to Avoid

• Never treat based on appearance alone: White exudate and red tonsils occur with both viral and bacterial infections 1
• Do not prescribe codeine: FDA black box warning prohibits codeine use in children under 12 years after tonsillectomy, and it should be avoided in acute pharyngitis as well 1
• Do not prescribe perioperative antibiotics if tonsillectomy is being considered—this is a strong recommendation against routine use 1
• Children under 3 years should not be routinely tested for Group A streptococcus, as it is uncommon and acute rheumatic fever is exceptionally rare in this age group 3

When to Consider Tonsillectomy

This single acute episode does NOT warrant tonsillectomy. 1 Tonsillectomy is only an option for recurrent throat infections meeting strict documentation criteria:

• ≥7 documented episodes in the past year, OR
• ≥5 documented episodes per year for 2 years, OR
• ≥3 documented episodes per year for 3 years 1, 7

Each episode must be documented with temperature ≥38.3°C, cervical adenopathy, tonsillar exudate, or positive Group A streptococcus test. 1 Watchful waiting is strongly recommended if these criteria are not met. 1

Follow-Up

Instruct caregivers to return if:

• Symptoms worsen or do not improve within 3-5 days
• Difficulty breathing or swallowing develops
• Signs of dehydration occur
• Fever persists beyond 3-4 days despite treatment

Document this episode thoroughly with all clinical findings and test results for future reference if recurrent infections develop. 1