Wednesday, 19 August 2020

Periorbital cellulitis in children

Eye infections in children are common.  The majority consist of simple infections of the conjunctiva (the layer that covers the sclera and the inside of the eyelid).  While these infections can be viral or bacterial, the tendency is for both to self-resolve and so infection confined to the conjunctiva can be managed conservatively.  The likelihood of benefit from topical antibiotics is low and there is a significant risk of the ingredients of antibiotic eye drops creating a chemical conjunctivitis and making things worse.  As a result, NICE suggests a limited number of scenarios in which topical antibiotics may be worthwhile in conjunctivitis.

It is worth mentioning two things about conjunctivitis:
  • Atypical conjunctivitis infections are more problematic.  If herpetic, chlamydia or gonococcal infection is suspected specialist input is advisable.
  • Neonates are the exception to this conservative approach to conjuntivitis.  For a full explanation regarding why and how to manage the newborn baby with an eye infection, click this link.
When infection spreads to the periorbital tissues, it is a different matter.  Infection of the skin and subcutaneous infections around the eye is usually bacterial and is associated with more invasive infection.
Image from Wikimedia Commons, the free media repository
Complications of invasive infection include:
  • Loss of eyesight (optic nerve damage, retinal detachment, retinal artery thrombosis)
  • Meningitis
  • Intracranial abscess
  • Cavernous sinus thrombosis
Although these complications are serious, they are mainly associated with orbital, or post septal cellulitis - infection of the tissues in the orbit (eye socket).  Infection confined to the pre-septal tissues is usually uncomplicated and low risk.
[Medical illustration credit to Naomi Snelson]

Telling the difference between pre-septal cellulitis and orbital cellulitis is about looking for signs and symptoms that could indicate orbital cellulitis.  In the absence of red-flag symptoms, it is assumed that the infection is pre-septal.

The management of pre-septal cellulitis has evolved considerably over time.  Many centres used to treat even pre-septal cellulitis as an inpatient with antibiotics given intravenously to begin with.  It is now much more normal to treat pre-septal cellulitis with oral antibiotics.
While some who have made this move choose to follow up and review the patient (often at about two days into their oral antibiotics) there are strong arguments for safety-netting and no planned follow-up.  When a child is sent home on oral antibiotics for pre-septal cellulitis, things will go one of two ways.  If treatment is successful, there will be significant improvement within the first two days.  If that happens, follow-up adds nothing.

If treatment is unsuccessful, signs and symptoms will worsen.  If that happens, there is a risk that a planned follow-up will delay escalation of treatment.  If things are getting worse, the child needs to be seen and admitted for intravenous antibiotics immediately, rather than waiting for their review appointment.

Safety-netting advice for children discharged on oral antibiotics for pre-septal cellulitis
Return for immediate assessment if-
  • the child becomes febrile or unwell
  • the swelling becomes visibly worse
  • eye movements are affected
  • vision is affected
  • the child is unable to take their antibiotics
  • the child starts vomiting
This simple approach is another great way to safely keep children out of hospitals.  That has always been a good thing but there has never been a better time to avoid unnecessary admissions than now.

Edward Snelson