Treatment of Periorbital Cellulitis
For uncomplicated periorbital cellulitis, start oral amoxicillin-clavulanate as first-line therapy for 5 days, extending only if clinical improvement has not occurred within this timeframe. 1
Antibiotic Selection Algorithm
First-Line Oral Therapy (Outpatient Management)
Amoxicillin-clavulanate is the preferred first-choice oral antibiotic for uncomplicated periorbital cellulitis, providing comprehensive coverage against both streptococci and Staphylococcus aureus (the predominant pathogen isolated in 74% of cultures). 1, 2
For penicillin-allergic patients, use clindamycin 300-450 mg orally every 6 hours (pediatric: 10-13 mg/kg/dose every 6-8 hours), which covers both streptococci and MRSA without requiring combination therapy. 1
Do not use doxycycline or trimethoprim-sulfamethoxazole as monotherapy for periorbital cellulitis, as their activity against beta-hemolytic streptococci is unreliable. 3
Parenteral Therapy (Severe Cases or Hospitalization)
For severe periorbital cellulitis requiring IV therapy, use cefazolin 1-2 g IV every 8 hours (pediatric: 25-50 mg/kg/dose) or nafcillin/oxacillin 2 g IV every 6 hours as first-line agents. 1
Ceftriaxone 50-75 mg/kg/day (max 2 g) once daily is an effective alternative for outpatient IV therapy with daily physician reassessment, demonstrating safety in 64 of 66 children (97% success rate) with mean duration of 4.1 days. 4
Vancomycin 15-20 mg/kg IV every 8-12 hours should be added if MRSA risk factors are present (penetrating trauma, purulent drainage, known MRSA colonization, or failure of beta-lactam therapy). 1
Treatment Duration
Treat for exactly 5 days if clinical improvement occurs, extending beyond 5 days only if the infection has not improved within this timeframe—this applies to both oral and IV regimens. 1
Traditional 7-10 day courses are no longer necessary for uncomplicated cases, as 5-day courses demonstrate equivalent efficacy. 3
Hospitalization Criteria
Admit patients immediately if any of the following are present:
- Systemic inflammatory response syndrome (SIRS): fever >38°C, tachycardia, tachypnea, or altered mental status 1
- Hemodynamic instability or hypotension 1
- Signs of orbital (postseptal) involvement: proptosis, ophthalmoplegia, pain with eye movement, or visual impairment 1
- Age <1 year or inability to tolerate oral medications 1
- Failure of outpatient therapy after 24-48 hours 1
When to Add MRSA Coverage
Do not routinely add MRSA coverage for typical non-purulent periorbital cellulitis. 1 MRSA is an uncommon cause of typical cellulitis, with beta-lactam monotherapy successful in 96% of cases. 3
Add MRSA-active antibiotics only when specific risk factors are present:
- Penetrating trauma or history of injection drug use 1
- Purulent drainage or exudate 1
- Evidence of MRSA infection elsewhere or known nasal MRSA colonization 1
- Failure to respond to beta-lactam therapy after 48-72 hours 1
Diagnostic Imaging and Workup
Obtain CT orbits with IV contrast to differentiate preseptal from postseptal cellulitis and identify complications (subperiosteal abscess, orbital abscess, cavernous sinus thrombosis) requiring surgical intervention. 1
Blood cultures are NOT routinely necessary for typical periorbital cellulitis, as they are positive in only 0-1% of preseptal cases and rarely change management. 1
Consider blood cultures only in patients with malignancy, severe systemic features, neutropenia, or unusual predisposing factors. 1
Essential Adjunctive Measures
Elevate the affected area to promote gravity drainage of edema and inflammatory substances, which hastens improvement. 1
Identify and treat predisposing conditions, particularly sinusitis (present in 43% of cases), which is the most frequent disease associated with periorbital cellulitis. 1, 2
Consider systemic corticosteroids (prednisone 40 mg daily for 7 days) in non-diabetic adult patients to reduce inflammation, though evidence is limited. 1
Common Pitfalls to Avoid
Do not automatically add MRSA coverage for typical non-purulent periorbital cellulitis without specific risk factors—this represents overtreatment and increases antibiotic resistance. 1
Do not extend treatment unnecessarily beyond 5 days if clinical improvement has occurred—residual erythema alone does not justify prolonged antibiotics. 1
Do not assume bilateral periorbital swelling is always cellulitis—consider venous congestion from cavernous sinus thrombosis, which requires immediate vascular imaging. 1
Do not delay surgical consultation if any signs of orbital involvement or necrotizing infection are present, as these progress rapidly. 1