Skip to content

Peri-orbital vs orbital cellulitis


6-year-old Chardonnay is brought to the emergency department by her mother.  Two or three days ago, she noticed what appeared to be a bite on her daughter’s eyelid.  Despite warm compresses, her eyelid has become progressively redder and inflamed, with the swelling extending onto her cheek.

Bottom line

Orbital cellulitis is sight-threatening and must be considered whenever there is any apparent cellulitis in the eye region.

A patient with orbital cellulitis is often toxic in appearance with a high-grade fever, proptosed eye and pain on eye movements.

Peri-orbital, or pre-septal, cellulitis is much more benign but it can be hard to differentiate between the two and so always err on the side of caution.

What’s the orbital septum?

It’s a continuation of the periosteum around the orbital margin, extending to the tarsal plates of the eyelids.

How might infection get into the orbit?

In the case of periorbital cellulitis, in 95% of cases, it is from local spread from a scratch, an insect bite or eczema. Occasionally, it can arise from pre-existing dacryocystitis.

As three sets of paranasal sinuses surround the orbit, these are a common source of infection in orbital cellulitis with the migration of colonised bacteria. This makes orbital cellulitis more common in teens than younger children due to a higher incidence of sinusitis. Orbital cellulitis may also arise as a result of haematogenous spread from any source of bacteraemia and may occasionally be the result of poor dental hygiene and a periosteal abscess.

How does a patient with peri-orbital cellulitis present?

There is often a gradual onset of unilateral eyelid oedema and erythema that may extend beyond the region of the orbit itself to the cheek and surrounding face.  It is often accompanied by a low-grade fever.  The eye itself is unaffected.

What organisms are commonly responsible?

Peri-orbital cellulitis may be caused by Staph. aureus, Strep. pneumoniae or occasionally Haemophilus influenza in the unimmunised.

How is peri-orbital cellulitis treated?

It can be hard to differentiate between orbital and peri-orbital cellulitis, and the consequences of getting it wrong are severe. If there is doubt, it should be treated as more serious orbital cellulitis.  Peri-orbital cellulitis responds well to amoxicillin-clavulanate or cephalexin.

How does a patient with orbital cellulitis present?

These infections are much more severe. The patient can be pretty toxic in appearance with a high-grade fever and lid oedema and erythema often confined to the eye socket itself as the infection is behind the orbital septum.  As the abscess develops, the eye becomes proptosed, and movements become painful.

What investigations are suggested in the work-up?

Other than the standard full blood exam and cultures, imaging of the orbit and sinuses with CT or MRI is needed to ascertain the presence or absence of an abscess and to aid operative planning.

How is orbital cellulitis treated?

The old surgical adage of  ‘if there’s pus about, let it out” holds true and maxillofacial, ENT or ophthalmic surgeons are keen to get these patients to theatre sooner rather than later.  Surgical drainage is augmented with high-dose IV antibiotics such as flucloxacillin and ceftriaxone.

What can go wrong if you get the diagnosis wrong?

In the early stages of the disease, it is easy to confuse orbital cellulitis for its less serious cousin, peri-orbital cellulitis.  However, unless caught early, orbital cellulitis may lead to blindness due to optic nerve compression, cavernous sinus thrombosis, osteomyelitis, meningitis or a cerebral abscess.


Chardonnay was diagnosed with peri-orbital cellulitis secondary to a mosquito bite and was treated with a week-long course of amoxicillin-clavulanate.  At a planned review after two days, she showed marked improvement.


Gellady AM, Shulman ST, Ayoub EM. Periorbital and orbital cellulitis in children. Pediatrics. 1978 Feb;61(2):272-7.

Malcolm A. Buchanan, Wisam Muen, Peter Heinz, Management of periorbital and orbital cellulitis, Paediatrics and Child Health, Volume 22, Issue 2, February 2012, Pages 72-77

Chaudhry IA, Al-Rashed W, Arat YO. The hot orbit: orbital cellulitis. Middle East Afr J Ophthalmol. 2012 Jan;19(1):34-42.

Royal Children’s Hospital, Melbourne, Clinical Practice Guidelines – Periorbital and orbital cellulitis.



No data was found

Leave a Reply

Your email address will not be published. Required fields are marked *

4 thoughts on “Peri-orbital vs orbital cellulitis”

  1. I am a patient, not Doctor. Maybe my experience can help someone with allergies and cellulitis!! I have orbital cellulitis now & I have extreme allergies. To environmental, foods, fungus, Rx, topicals, animals, a lot! This week I was diagnosed with orbital cellulitis in my left eye. I was given an antibiotic shot, prescription eyedrops, and an oral antibiotic Clindamycin (sp?). After 4 days, I was still in pain if I was blinking or touching my face. Had left side neck pain as well. Face was red/purple around eye area after diagnosis. My bottom lashes fell out. My symptoms started out looking like 1 stye. Then 2 styes. 1 on lash area & 1 inside the lid. Took 3 days to see a dramatic appearance on my face. Boom it was noticeably worse. Vision changes, fluid sacks inside the lid, then swelling down from lid—toward my cheek/nose, & my body felt like I was getting sick.
    I’m a 40 year old female. So I’m proof adults get cellulitis too. Thankfully I don’t have kids or a husband who needs me~ bc there is no way I could take care of them while going through this. But I could use some encouragement for the fear I feel about loosing my vision and or my life.
    I did not have blood tests or MRI or IV Rx. I was diagnosed by my PCP and an Ophthalmologist—by the look & symptoms alone.
    An allergic reaction doesn’t feel anything like cellulitis. The one time I went into anaphylactic shock this year—my eyes were puffy but 1 eye didn’t look different and bruised. They both looked red on the eyeball and top & bottom lid were pink and itchy. Other parts of my body showed allergic reactions as well. With trouble breathing and swallowing.
    Theres a big difference in the pain and the look of the eye & skin.
    Doctors told me to seek medical help with eye situations. As they can be life threatening or altering. I’ve tried to stay busy (to keep my mind off the “could’ve’s). I don’t think I ever had a fever. But I didn’t use a thermometer at home.

  2. Any tips on discerning an early peri-orbital cellulitis from an allergic reaction?
    Ive seen thee a few times and often feel i over treat. Obviously bilateral is easy, but i have seen many unilateral ones as well.
    Early supervised trial of anti-histamine?
    Prophylactic oral augmentin?
    I’d be interested in your thoughts

    1. Great question – I often come across this problem in ED. I just use clinical judgement. Shiny, red and painful and it’s more likely to be cellulitis. Less ref, more diffuse then is could be allergy. Not sure if waiting in ED for a trial of antihistamine will help though – how likely are you to see a dramatic response? We sometimes review the next day and make a decision re antibiotics then (ie don’t give antibiotics, advise to use antihistamines and come back the next day, but return before if worsening). Would be interested to hear what other people have to say on this though.