The Case

A five year old male presents with right eye swelling and redness. he has been afebrile but a bit congested for the past week and a half. He is otherwise well appearing with no history of trauma. his visual acuity is normal, and he has no pain with extra ocular movements.

The Diagnosis

This is preseptal cellulitis (AKA periorbital cellulitis) which is a soft tissue infection of the tissues in front of the orbit. The most common bacteria that cause it are Staphylococcus aureus and S. epidermidis and S. pyogenes  which are implicated in ~75% of cases. If there is a personal or family history of MRSA you should worry about that – and remember MRSA is carried in the nostrils. H. influenzae type b was the most common cause in the pre-vaccination era. Its is most often unilateral – bilateral preseptal cellulitis is possible, but you should be thinking of other diagnoses and looking for dependent edema and rashes elsewhere if both eyes are swollen. Here are some of the most common causes:

• Rhinosinusitis (particularly ethmoid sinusitis)
• Stye
• Local trauma
• Insect bites
• Dental infections
• Dacrocystitis
• Impetigo
• Hematogenous spread

With all that in mind it is important to note that preseptal cellulitis is a clinical diagnosis. No labs, imaging, or other tests are strictly necessary to make the diagnosis which should be suspected in a nontoxic child with unilateral eyelid swelling, redness, tenderness, and/or warmth. These findings can be subtle or the eye can be completely swollen shut. The most important competing diagnosis is orbital cellulitis – which is much worse. Features concerning for orbital cellulitis.

• Visual changes (blurry)
• Proptosis
• Chemosis (edema of the conjunctiva – they look puffy)
• Restricted Range of Movement of the Eye
• Increased intraorbital pressure

If you are not sure if it is preseptal or orbital cellulitis, especially in cases in which you can’t open he eyelids to examine the globe, CT scan with contrast is the test of choice to rule out orbital cellulitis. An elevated WBC, ESR, and/or CRP and nonspecific findings that may be abnormal in orbital cellulitis – but they don’t actually make the diagnosis. Blood cultures are far less helpful than ocular cultures – but neither is paramount to making the diagnosis and developing your treatment plan.

Management

Preseptal cellulitis is a bacterial infection and therefore you should treat with antibiotics. You should think about the cause and tailor antibiotic management to it. Here is a general stratagem – but as always you should consider local practice patterns and antibiotic resistance in your decision making. If the cause is…

• Rhinosinusitis – Amoxicillin/Clavulanate or a 2nd or 3rd generation cephalosporin
• Stye – 1st generation cephalosporin (cephalexin), trimethoprim/sulfamethoxazole or Clindamycin if MRSA is suspected
• Local trauma and insect bites – 1st generation cephalosporin (cephalexin), trimethoprim/sulfamethoxazole or Clindamycin if MRSA is suspected
• Dental infections – Clindamycin or Amoxicillin/Calvulanate
• Stye or dacrocystitis – 1st generation cephalosporin, or Clindamycin if MRSA is a concern
• Impetigo – Clindamycin or 1st generation cephalosporin
• Hematogenous Spread – 3rd generation cephalosporin PLUS clindamycin or vancomycin

For mild or simple preseptal cellulitis (just eyelid redness and mild swelling in a well-appearing child) you can choose one of the oral antibiotics listed above and treat for 7 to 10 days. A well appearing child with fever, but a reassuring exam can also be treated orally. An ill-appearing child with systemic signs is a candidate for IV antibiotics and admission. If they don’t get better within 1 to 2 days of antibiotics you should reconsider your treatment plan and whether or not you have made the correct diagnosis. This would be a good time to get ocular (and sigh, blood) cultures as well as get a CT scan and consider consulting Ophthalmology. A child can develop orbital cellulitis, or intracranial spread from prespetal cellulitis.

References

Fox S. Periorbital cellultiis. Pediatric EM Morsels. March 29, 2013. https://pedemmorsels.com/periorbital-cellulitis/. Accessed October 20, 2022.

Andrea Hauser, Simone Fogarasi; Periorbital and Orbital Cellulitis. Pediatr Rev June 2010; 31 (6): 242–249. https://doi.org/10.1542/pir.31-6-242

Murphy, D.C., Meghji, S., Alfiky, M. and Bath, A.P. (2021), Paediatric periorbital cellulitis: A 10-year retrospective case series review. J Paediatr Child Health, 57: 227-233. https://doi.org/10.1111/jpc.15179