What is the recommended treatment for preseptal cellulitis?

Treatment of Preseptal Cellulitis

For mild to moderate preseptal cellulitis, initiate oral antibiotics targeting beta-hemolytic streptococci with penicillin, amoxicillin, dicloxacillin, or cephalexin for 5 days, extending treatment only if no improvement occurs within this period. 1

First-Line Antimicrobial Selection

Outpatient Treatment (Mild to Moderate Cases)

• Oral beta-lactams are the cornerstone of therapy, specifically penicillin, amoxicillin, dicloxacillin, or cephalexin, as streptococci (particularly beta-hemolytic streptococci) are the primary pathogens. 1
• For pediatric patients with preseptal cellulitis associated with acute bacterial sinusitis (eyelid <50% closed), high-dose amoxicillin-clavulanate provides comprehensive coverage and should be used with daily follow-up until definite improvement is noted. 1
• Treatment duration is 5 days, with extension only if clinical improvement is not evident after this period. 1

Penicillin-Allergic Patients

• Clindamycin is the preferred alternative with 99.5% susceptibility for streptococci. 1
• Erythromycin is an alternative option, though resistance is increasing. 1

Common pitfall: Fluoroquinolones should not be used as first-line therapy due to inadequate streptococcal coverage, despite their approval for uncomplicated cellulitis. 2

MRSA Coverage Considerations

MRSA coverage is not routinely recommended for typical preseptal cellulitis. However, consider adding MRSA-active antibiotics when specific risk factors are present: 1

• Penetrating trauma
• Evidence of MRSA infection elsewhere or nasal colonization
• Injection drug use
• Purulent drainage

For these scenarios, vancomycin or another antimicrobial effective against both MRSA and streptococci should be used. 1

Hospitalization Criteria and Severe Cases

Hospitalize patients and initiate intravenous antibiotics when any of the following are present: 1

• Systemic inflammatory response syndrome (SIRS), altered mental status, or hemodynamic instability
• Concern for deeper infection (orbital involvement)
• Immunocompromised status
• Failed outpatient treatment
• No improvement within 24-48 hours of appropriate oral therapy

Severe Infection Management

• Intravenous vancomycin is recommended to cover possible methicillin-resistant organisms and streptococci. 1
• In pediatric cases with proptosis, impaired visual acuity, or impaired/painful extraocular mobility, perform contrast-enhanced CT and consult otolaryngology, ophthalmology, and infectious disease. 1

Adjunctive Measures

• Elevate the affected area to promote gravity drainage of edema—failure to do so delays improvement. 1
• Consider systemic corticosteroids (prednisone 40 mg daily for 7 days) in non-diabetic adult patients to hasten resolution. 1

Monitoring and Follow-Up

• Patients should show improvement within 24-48 hours of appropriate antibiotic therapy. 1
• If no improvement occurs within 72 hours, consider changing antibiotics, obtaining imaging to rule out orbital involvement or abscess formation, or admitting for IV antibiotics. 1
• C-reactive protein >120 mg/L suggests orbital rather than preseptal involvement and warrants more aggressive evaluation. 3

Prevention of Recurrence

• Identify and treat predisposing conditions such as sinusitis, edema, and toe web abnormalities. 1
• For patients with 3-4 episodes per year despite addressing predisposing factors, consider prophylactic antibiotics such as oral penicillin or erythromycin twice daily for 4-52 weeks. 1

Key Clinical Pearls

Streptococcus pyogenes is the predominant pathogen in preseptal cellulitis, though Staphylococcus aureus can be involved, particularly with trauma or abscess formation. 4, 5 While rare, severe complications including streptococcal toxic shock syndrome can occur in immunocompromised adults, emphasizing the importance of appropriate antibiotic selection and timely intervention. 4