Orbital cellulitis is characterized by fever, proptosis, restriction of extraocular movements, and swelling with redness of the lids
Immediate treatment with intravenous antibiotics is necessary to prevent optic nerve damage and spread of infection to the cavernous sinuses, meninges, and brain
Infection of the paranasal sinuses is the usual underlying cause
Infecting organisms include S pneumoniae, the incidence of which has been reduced by the administration of pneumococcal vaccine; other streptococci, such as the anginosus group; H influenzae and, less commonly, S aureus including MRSA
Penicillinase-resistant penicillin, such as nafcillin, is recommended, possibly together with metronidazole or clindamycin to treat anaerobic infections
If trauma is the underlying cause, a cephalosporin, such as cefazolin or ceftriaxone, should be added to ensure coverage for S aureus and group A beta-hemolytic streptococci
If MRSA infection is a concern, vancomycin or clindamycin may be required
For patients with penicillin hypersensitivity, vancomycin, levofloxacin, and metronidazole are recommended
The response to antibiotics is usually excellent, but surgery may be required to drain the paranasal sinuses or orbital abscess
In immunocompromised patients, zygomycosis must be considered

When to Refer

All patients with suspected orbital cellulitis must be referred emergently to an ophthalmologist