orbital cellulitis case

orbit

orbit

A 35-year-old man presents to his GP with erythematous, swollen right upper and lower eyelids, worsening over the previous 2 days. He is unable to open them. He feels unwell and has a high temperature. History of chronic sinusitis 4 years ago and glasses wearing since 10 years. Examination reveals marked lid swelling, and on manual opening of the lids a proptosis with chemotic injected conjunctiva. Eye movements are limited in all directions. Visual acuity and colour vision are normal, and there is no relative afferent pupillary defect. The optic disc and retina also appear normal.

OSPE

Diagnosis

Right Orbital Cellulitis

1. Definitions

Term	Location
Preseptal cellulitis	Infection of eyelid/anterior eyelid tissues, anterior to the orbital septum
Orbital cellulitis	Infection of orbital fat and ocular muscles, posterior to the septum

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2. Key Clinical Features

Feature	Preseptal Cellulitis	Orbital Cellulitis
Location	Infection of eyelid/anterior eyelid tissues, anterior to the orbital septum	Infection of orbital fat and ocular muscles, posterior to the septum
Eyelid swelling/erythema	Yes	Yes
Tenderness	Mild–moderate	Moderate–severe
Ocular pain	Often, but no pain with eye movement	Worse on eye movement
Eye movements (motility)	Full range	Restricted
Proptosis	No	Yes
Vision changes	No	May have ↓ visual acuity / RAPD
Systemic signs	May have low-grade fever	Frequently fever, malaise
Skin warmth	May feel warm	Often hot to touch

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3. Investigations

• Clinical exam: carefully assess eye movements, pupillary responses, visual acuity.

• Imaging

  • CT or MRI orbit with contrast:

    • Confirms posterior (“orbital”) involvement

    • Rules out subperiosteal or intra-orbital abscess

    • Looks for sinus disease, foreign body, tumor

• Laboratory

  • CBC (↑ WBC)

  • Blood cultures if febrile

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4. Management

A. Preseptal (Periorbital) Cellulitis

1. Outpatient (if well-appearing, no systemic signs)

   • Oral antibiotics covering Staph/Strep (e.g. cephalexin, dicloxacillin) for 7–10 days

2. Admission & IV antibiotics if:

   • Toxic appearance or high fever

   • Very young child (<1 year)

   • Immunocompromised

B. Orbital Cellulitis

1. Hospitalize immediately

2. Empiric IV broad-spectrum antibiotics, covering Gram-positives (including MRSA), Gram-negatives and anaerobes.

   • e.g. vancomycin plus a third-generation cephalosporin (ceftriaxone or cefotaxime) ± metronidazole

3. Consider systemic steroids (e.g. dexamethasone) to reduce inflammation and orbital pressure—but only after 24–48 h of effective IV antibiotics and under close monitoring.

4. Surgical drainage if:

   • Subperiosteal or intra-orbital abscess on imaging

   • No clinical improvement within 24–48 h of antibiotics

   • Evidence of compressive optic neuropathy

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5. “Red Flags” Suggesting Orbital Involvement

• Proptosis (forward displacement of the globe)

• Pain or limitation on eye movement

• ↓ Visual acuity, RAPD

• High fever, systemic toxicity

• “Hot” (warm) eyelid skin

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Key take-home:

• Preseptal cellulitis → often outpatient, oral antibiotics, good follow-up.

• Orbital cellulitis → emergency admission, IV antibiotics, imaging, possible surgery.

Diagnosis

Right Orbital cellulitis

Differential diagnosis

• Uveitis
• Sudden painful decrease of vision
• ACG
• Optic neuritis
• Endophthlmitis
• Keratitis

DDx: (red painful eye)

• Endophthlmitis.
• Keratitis.
• Uveitis.
• Glaucoma.

DDx: (unilateral proptosis)

• Trauma.
• Tumor.
• Orbital cellulitis.
• Carotid-cavernous fistula.
• Orbital varix.
• Orbital cyst.
• Orbital varicose.