Periorbital and orbital cellulitis (pediatrics): Clinical sciences

Periorbital and orbital cellulitis are bacterial infections of the soft tissues within or around the orbit. Based on the relation of the infection to the orbital septum and the presence or absence of increased intraorbital pressure, you can differentiate orbital from periorbital cellulitis.

Orbital cellulitis occurs posterior to the orbital septum and is associated with increased intraorbital pressure, while periorbital cellulitis occurs in the soft tissues anterior to the orbital septum and is not associated with increased intraorbital pressure.Now, if your patient presents with a chief concern suggesting orbital or periorbital cellulitis, you should first perform an ABCDE assessment to determine whether the patient is unstable or stable.

If unstable, stabilize their airway, breathing, and circulation. Next, obtain IV access, consider IV fluids, and put the patient on continuous vital sign monitoring, including blood pressure, heart rate, and pulse oximetry.

Finally, if needed, don’t forget to provide supplemental oxygen. Now, let’s go back and discuss stable patients.

First, obtain a focused history and physical examination. History typically reveals unilateral eye pain and swelling.

In some cases, the patient or their caregiver may report fever, a recent sinus or dental infection, or a recent trauma to the eye or surrounding skin, like an insect bite or even impetigo.

The physical exam reveals unilateral erythema around the orbit, as well as warmth, tenderness to palpation, and swelling of the upper or lower eyelid.

Now, here’s a clinical pearl to keep in mind! If your patient has severe pain or swelling, you might not be able to visualize the eye well enough to obtain a thorough exam.

In this case, you should order a CT scan of the orbit to establish a diagnosis.At this point, you should suspect orbital or periorbital cellulitis, so your next step is to assess your patient for signs of increased intraorbital pressure.

These include blurred vision or reduced visual acuity, ophthalmoplegia, proptosis, chemosis, and abnormal corneal light reflex.If your patient presents with no signs of increased intraorbital pressure, diagnose periorbital cellulitis, which can result from minor skin trauma like abrasions or insect bites.

In most cases, this is a clinical diagnosis, so you won’t need labs or imaging. In other words, you can proceed straight to treatment, which primarily relies on penicillin combined with oral beta-lactamase inhibitors, such as amoxicillin-clavulanate, which cover Staphylococcus, Streptococcus, and other gram-positive skin flora.Now, let’s go back and take a look at patients who present with signs of increased intraorbital pressure.

In this case, diagnose orbital cellulitis. As far as management goes, first, you should admit your patient to the hospital, initiate IV antibiotics, and consult your ophthalmology team for a complete eye examination.

Most patients with orbital cellulitis have a coexisting sinus or dental infection, so choose an antibiotic that covers Staphylococcus and Streptococcus species, such as a second- or third-generation cephalosporin.

Additionally, consider adding an antibiotic that provides coverage against methicillin-resistant Staphylococcus aureus, or MRSA, such as IV clindamycin.

Once you initiate the treatment, your next step is to assess whether there are any indications for imaging. These include deteriorating visual acuity, gross proptosis, or ophthalmoplegia; as well as signs of central nervous system involvement, like focal neurologic deficits, seizures, and altered mental status.

If there are no indications for imaging, you can make a clinical diagnosis of uncomplicated orbital cellulitis and continue the treatment with IV antibiotics.On the other hand, if indications for imaging are present, order a CT scan of the sinuses and orbits with contrast.

If the CT reveals only diffuse fat infiltration diagnose severe orbital cellulitis. However, if the CT reveals diffuse fat infiltration as well as the evidence of an abscess within the orbit, diagnose orbital cellulitis complicated by an orbital abscess.

Finally, if the CT reveals diffuse fat infiltration and an abscess in the subperiosteal space, diagnose orbital cellulitis complicated by a subperiosteal abscess.

In each of these cases, you should continue the IV antibiotics and consider consulting your surgery team for possible abscess drainage.Now here’s a high-yield fact to keep in mind!

Untreated orbital cellulitis can lead to severe complications like cavernous sinus thrombosis, which can cause vision loss or even death.

Clinical findings alone are not enough to differentiate cavernous sinus thrombosis from orbital cellulitis, so if your patient has progressively worsening signs suggesting increased intraorbital pressure, consider ordering an MRI to rule out cavernous sinus thrombosis.

Alright, as a quick recap… Periorbital and orbital cellulitis are bacterial infections of the soft tissues surrounding the orbit.

Periorbital cellulitis is an infection anterior to the orbital septum that does not cause signs of increased intraorbital pressure and requires oral antibiotics that contain a beta-lactamase inhibitor.

On the flip side, orbital cellulitis is an infection posterior to the orbital septum and is diagnosed based on signs indicating increased intraorbital pressure.

Once you diagnose orbital cellulitis, admit your patient to the hospital, begin IV antibiotics, and consult your ophthalmology team for a complete eye examination.

If you suspect severe or complicated cellulitis, obtain a CT scan with contrast of the sinuses and orbit to look for severe orbital cellulitis, as well as orbital and subperiosteal abscesses,