What is the appropriate treatment approach for preseptal cellulitis?

Management of Preseptal Cellulitis

Beta-lactam antibiotics targeting beta-hemolytic streptococci, such as amoxicillin-clavulanate, cephalexin, or penicillin, should be used as first-line therapy for preseptal cellulitis for a 5-6 day course. 1

Etiology and Pathophysiology

Preseptal cellulitis is an infection of the eyelid and periorbital tissues anterior to the orbital septum. The most common causative organisms are:

• Beta-hemolytic streptococci (most common)
• Staphylococcus aureus (including MRSA in some cases)
• Less commonly: Haemophilus influenzae (less frequent since vaccination), Proteus species 2, and other organisms

Initial Assessment

• Differentiate from orbital cellulitis (more serious condition):

  • Preseptal: Eyelid swelling, erythema, tenderness; normal visual acuity, no restriction of extraocular movements, no proptosis
  • Orbital: Similar symptoms plus vision changes, restricted/painful eye movements, proptosis, chemosis

• Identify predisposing factors:

  • Sinusitis (common in children) 3
  • Trauma to eyelid
  • Upper respiratory tract infection
  • Local skin infection
  • Insect bite
  • Immunocompromising conditions 4

Treatment Algorithm

Outpatient Management (Mild to Moderate Cases)

1. First-line oral antibiotics (5-6 day course) 1:

   • Adults: Amoxicillin-clavulanate 875/125 mg twice daily OR
   • Cephalexin 500 mg four times daily OR
   • Clindamycin 600 mg three times daily (for penicillin-allergic patients)

2. For patients with risk factors for MRSA:

   • Clindamycin 600 mg orally three times daily OR
   • Doxycycline 100 mg twice daily (not for children <8 years) OR
   • Linezolid 600 mg twice daily for more severe cases

Inpatient Management (Severe Cases)

1. Indications for hospitalization:

   • Severe infection
   • Failure to respond to oral antibiotics
   • Toxic appearance
   • Young children
   • Immunocompromised patients
   • Concern for progression to orbital cellulitis

2. Intravenous antibiotics:

   • Cefazolin OR
   • Nafcillin OR
   • Vancomycin (if MRSA suspected) 1
   • Consider adding gram-negative coverage if indicated

Monitoring and Follow-up

• Daily follow-up until definite improvement is noted
• If no improvement within 24-48 hours:
  • Reassess diagnosis (consider orbital involvement)
  • Obtain cultures if possible
  • Consider imaging (CT scan) to rule out orbital involvement or abscess
  • Adjust antibiotics based on clinical response or culture results

Special Considerations

• Abscess formation: If an abscess develops, incision and drainage may be necessary 4

• Adjunctive measures:

  • Warm compresses to affected area
  • Elevation of head to reduce edema
  • Consider systemic corticosteroids in select adult patients to hasten resolution (contraindicated in diabetics and pregnant women) 5, 1

• MRSA coverage: Consider if patient has risk factors (prior MRSA infection, recent hospitalization, antibiotic use) or if not responding to beta-lactam therapy 1, 6

Prevention of Recurrence

• Treat underlying conditions:

  • Chronic sinusitis
  • Blepharitis
  • Dacryocystitis
  • Skin conditions (eczema, etc.)

• Maintain good hygiene:

  • Keep draining wounds covered with clean, dry bandages
  • Maintain good personal hygiene
  • Avoid sharing personal items 1

Potential Complications

• Progression to orbital cellulitis
• Vision loss (if untreated and spreads to orbit)
• Cavernous sinus thrombosis
• Meningitis
• Brain abscess
• Streptococcal toxic shock syndrome (rare) 4

Preseptal cellulitis typically has a good prognosis with appropriate and timely antibiotic therapy 3. The shift in causative organisms, including the emergence of community-acquired MRSA, necessitates awareness of local resistance patterns when selecting empiric therapy 6.