What is the appropriate treatment for a patient with neutrophilia and pharyngitis, indicating a potential bacterial or viral infection?

Elevated Neutrophils and Sore Throat: Bacterial vs Viral Etiology

Elevated neutrophils with sore throat most commonly indicates a viral infection, as viruses are the predominant cause of acute pharyngitis, and neutrophilia alone does not reliably distinguish bacterial from viral etiology. 1

Clinical Assessment Framework

The key distinction is that Group A Streptococcus (GAS) is the only common bacterial cause of pharyngitis requiring antibiotic treatment, accounting for less than half of all pharyngitis cases. 1 The signs and symptoms of bacterial and viral pharyngitis overlap so broadly that accurate diagnosis on clinical grounds alone is impossible. 1

Features Suggesting Viral Etiology

Viral pharyngitis is more likely when patients present with: 1

• Cough (most important discriminator)
• Nasal congestion or coryza
• Conjunctivitis
• Hoarseness
• Diarrhea
• Oropharyngeal lesions (ulcers or vesicles)

Common viral causes include rhinovirus, coronavirus, adenovirus, parainfluenza, respiratory syncytial virus, Epstein-Barr virus, and influenza. 1

Features Suggesting Bacterial (GAS) Etiology

Use the Modified Centor Criteria to assess probability of GAS infection: 1

• Fever by history (1 point)
• Tonsillar exudates (1 point)
• Tender anterior cervical adenopathy (1 point)
• Absence of cough (1 point)

Additional concerning features include: 1

• Persistent fever
• Rigors and night sweats
• Swollen tonsils
• Palatal petechiae
• Scarlatiniform rash

Diagnostic Algorithm

Patients with fewer than 3 Centor criteria do not need testing and should not receive antibiotics. 1 For patients meeting 3 or more criteria:

1. Perform rapid antigen detection test (RADT) or throat culture before initiating antibiotics 1, 2
2. Throat culture remains the gold standard, though RADT sensitivity and specificity have improved significantly 3
3. After negative RADT in children and adolescents, obtain throat culture for confirmation 1
4. In adults, negative RADT alone is sufficient to exclude GAS 1

Critical Pitfall to Avoid

Do not use neutrophil count as a diagnostic criterion. Neutrophilia occurs in both viral and bacterial infections and does not reliably differentiate etiology. The clinical scoring systems and microbiologic testing are far more accurate. 1

Treatment Decisions

For Confirmed GAS Pharyngitis

First-line treatment is penicillin or amoxicillin for 10 days: 4, 2, 3

• Amoxicillin is equally effective and more palatable than penicillin
• Dosing for adults and children ≥40 kg: 500 mg every 12 hours or 250 mg every 8 hours for mild/moderate infections 4
• For severe infections: 875 mg every 12 hours or 500 mg every 8 hours 4

For penicillin-allergic patients (non-anaphylactic): 2, 3

• First-generation cephalosporins are recommended
• Avoid azithromycin and clarithromycin due to significant resistance in many U.S. regions 2

For Viral Pharyngitis

Do not initiate antibiotics. 1 Provide symptomatic treatment only:

• Analgesics (NSAIDs or acetaminophen)
• Reassurance about self-limited nature
• Steroids are not recommended 2

Red Flags Requiring Urgent Evaluation

Immediately evaluate for serious complications if patient presents with: 1

• Difficulty swallowing or drooling
• Neck tenderness or swelling
• Trismus (inability to open mouth)
• Uvular deviation
• "Hot potato" voice
• Stridor or airway compromise

These suggest peritonsillar abscess, parapharyngeal abscess, epiglottitis, or Lemierre syndrome requiring urgent intervention. 1

Follow-Up Considerations

Reevaluate patients with worsening symptoms after appropriate antibiotic initiation or symptoms lasting >5 days after treatment start. 2 Chronic GAS carriers (positive tests without active infection) are common and generally do not require treatment, as they are at low risk for complications and transmission. 3