What is the treatment for orbital cellulitis?

Treatment of Orbital Cellulitis

The treatment of orbital cellulitis requires immediate initiation of broad-spectrum intravenous antibiotics with coverage for common pathogens including Streptococcus pneumoniae, Haemophilus influenzae, Streptococcus pyogenes, Moraxella species, Staphylococcus aureus, and anaerobes, along with appropriate imaging and possible surgical intervention depending on the severity and complications. 1

Classification and Diagnosis

• Orbital cellulitis must be differentiated from preseptal cellulitis, as management and prognosis differ significantly 1, 2
• Clinical signs of orbital (postseptal) cellulitis include proptosis, limitation of extraocular movements, and possible visual compromise 3
• CT scan of the orbits with IV contrast is the most useful initial imaging modality to differentiate preseptal from postseptal cellulitis and to identify complications such as abscess formation 3, 4
• MRI with contrast can be complementary to CT and is particularly useful when intracranial complications are suspected 3

Antibiotic Treatment

• Start broad-spectrum intravenous antibiotics immediately after obtaining cultures 1
• Recommended empiric antibiotic regimens include:
  • High-dose amoxicillin-clavulanate for comprehensive coverage 1, 4
  • Consider adding vancomycin if MRSA is suspected 1, 4
  • Add clindamycin for anaerobic coverage 1
• Continue intravenous antibiotics until significant clinical improvement, then transition to oral antibiotics to complete a total 10-14 day course 1

Multidisciplinary Management

• Consult ophthalmology, otorhinolaryngology, and infectious disease specialists 1, 4
• Perform daily assessment of visual function and ocular movements to monitor response to therapy 1
• Elevate the head to facilitate drainage of edema 1

Surgical Intervention

• Surgical intervention is indicated for:
  • Large abscesses with significant mass effect 5
  • Concurrent intracranial involvement 5
  • Poor response to initial medical therapy after 24-36 hours 6
  • Presence of orbital abscess with gas formation 5
• Small or medially located abscesses may respond well to medical management alone 5, 6

Monitoring and Complications

• Potential complications include vision loss, cavernous sinus thrombosis, brain abscess, meningitis, and death 2, 7
• If orbital cellulitis is secondary to sinusitis, drainage of sinus contents and establishment of ventilation may be necessary 2
• Monitor for signs of intracranial extension, which is more common with frontal sinusitis 5

Special Considerations

• Preseptal cellulitis cases that are mild can be treated on an outpatient basis with oral antibiotics 1
• Orbital cellulitis is more common in children and young adults, with sinusitis being the most common predisposing factor 2, 7
• In children older than 15 years and adults, infections are more likely to be polymicrobial 2

Common Pitfalls to Avoid

• Delaying appropriate imaging in cases with concerning features such as proptosis or visual changes 4
• Inadequate antibiotic coverage, particularly failing to consider MRSA when risk factors are present 4
• Not recognizing the need for surgical intervention when medical management is failing 5, 6