Preseptal Cellulitis

Preseptal (periorbital) cellulitis is infection of the soft tissues of the eyelid anterior to the orbital septum, without involvement of the orbit proper. It is more common and less dangerous than orbital cellulitis but can progress to it.

• Sources: skin wounds and insect bites, eyelid infections (hordeolum, impetigo, dacryocystitis, blepharitis), sinusitis, upper respiratory infection, dental infection, and bacteraemia.
• Organisms: Staphylococcus aureus (including MRSA) and Streptococcus pyogenes, Streptococcus pneumoniae, and Haemophilus influenzae type b in unvaccinated infants; in children after sinusitis, polymicrobial infection with anaerobes.
• Most cases occur in children under 5 years, and in diabetic and immunosuppressed adults.

• Unilateral lid erythema, oedema, warmth, and tenderness, with fever, and lid swelling that may close the eye.
• Normal visual acuity, normal colour vision, normal pupils without a relative afferent pupillary defect, no proptosis, full painless eye movements, and no chemosis.
• Recent insect bite, trauma, or sinus symptoms.
• Warning features suggesting progression to orbital involvement: proptosis, painful or restricted eye movements, diplopia, visual loss, abnormal pupil, severe toxicity, and high fever.

• Clinical with a complete eye examination (vision, pupils, colour vision, eye movements, proptosis, intraocular pressure); in a child with a swollen lid, abduct the lid gently to examine the eye, with sedation if necessary.
• Full blood count, CRP, and blood culture in children who are unwell, in infants, and in those with fever; swab of any wound or pus for culture.
• Contrast CT of the orbits and sinuses is indicated when the eye cannot be examined reliably, orbital signs are present, there is no improvement in 24 to 48 hours, there are neurological features, or the child is systemically very ill.
• Differential diagnosis: orbital cellulitis, allergic angioedema, insect bite reaction, herpes zoster, chalazion, dacryocystitis, and orbital tumour (rhabdomyosarcoma, lymphoma).

• Mild cases in well adults and older children can be managed as outpatients with close review at 24 to 48 hours.
  • Adults: amoxicillin clavulanate 625 mg orally every 8 hours (or 875/125 mg every 12 hours) for 7 to 10 days; alternatives cefalexin 500 mg every 6 hours, or doxycycline 100 mg twice daily.
  • MRSA suspected or penicillin allergic: clindamycin 300 mg to 450 mg orally every 6 to 8 hours, or trimethoprim-sulfamethoxazole 160 mg/800 mg twice daily for 7 to 10 days with additional streptococcal cover (amoxicillin 500 mg three times daily).
  • Children: amoxicillin clavulanate 25 to 45 mg/kg/day of amoxicillin component in 2 to 3 divided doses for 7 to 10 days, or cefalexin 25 to 50 mg/kg/day in 3 to 4 doses; clindamycin 10 to 30 mg/kg/day in 3 to 4 doses for MRSA.
• Admission and intravenous therapy for infants under 12 months, toxic children, no oral tolerance, no improvement after 24 to 48 hours of oral therapy, diabetes, immunosuppression, and doubtful follow up: ceftriaxone 1 g to 2 g daily (child 50 to 100 mg/kg/day), or cefazolin 1 g every 8 hours (child 100 mg/kg/day divided), with vancomycin 15 mg/kg every 8 to 12 hours when MRSA is a concern, then change to oral antibiotics when afebrile and improving to complete 10 to 14 days.
• Warm compresses, analgesia, and treatment of the source: nasal decongestant (oxymetazoline 0.05 percent twice daily for up to 3 days) and saline for sinusitis, drainage of abscess, dental treatment.
• Review after 24 to 48 hours; failure to improve warrants CT and escalation.
• Complications: orbital cellulitis, abscess, sepsis, cavernous sinus thrombosis, and meningitis.
• Prevention: Haemophilus influenzae type b and pneumococcal vaccination, and early treatment of skin and eyelid infections.