Preseptal cellulitis, also known as periorbital cellulitis, is an infection in the tissues around the eye.

It can be caused by minor trauma to the eyelid, such as an insect bite, or the spread of another infection, such as a sinus infection.

Preseptal cellulitis causes redness and swelling of the eyelid and the skin surrounding your eyes.

The infection can be successfully treated with antibiotics and close monitoring, but it can be serious if left untreated.

Preseptal cellulitis can cause permanent vision problems or even blindness if it spreads to the eye socket. It should be treated right away to prevent complications.

The main difference between preseptal and orbital cellulitis is the location of the infection:

  • Orbital cellulitis occurs in the soft tissues of the orbit posterior (behind) the orbital septum. The orbital septum is a thin membrane covering the front of the eyeball.
  • Preseptal cellulitis occurs in the tissue of the eyelids and periocular region anterior (in front of) the orbital septum.

Orbital cellulitis is considered much more serious than preseptal cellulitis. Orbital cellulitis can lead to:

  • permanent partial vision loss
  • total blindness
  • other life-threatening complications

Preseptal cellulitis can spread to the eye socket and lead to orbital cellulitis if not treated right away.

Preseptal cellulitis vs. blepharitis

Blepharitis is inflammation of the eyelids that typically occurs when the oil glands located near the base of the eyelashes become clogged.

The eyelids may become red and swollen, similar to the symptoms of preseptal cellulitis.

However, people with blepharitis will usually have additional symptoms such as:

  • itchiness or burning
  • oily eyelids
  • sensitivity to light
  • feeling like something is stuck in the eye
  • a crust that develops on the eyelashes.

Blepharitis has many causes, including:

Unlike preseptal cellulitis, blepharitis is often a chronic condition that requires daily management.

Though both conditions can be caused by bacterial infections, their treatment methods are different.

Blepharitis is usually be treated with topical antibiotics (eye drops or ointment), while preseptal cellulitis is treated with oral or intravenous (IV) antibiotics.

The symptoms of preseptal cellulitis may include:

Preseptal cellulitis can be caused by:

  • bacteria
  • viruses
  • fungi
  • helminths (parasitic worms)

The majority of these infections are caused by bacteria.

A bacterial infection can spread from an infection of the sinuses (sinusitis) or another part of the eye.

It can also occur after minor trauma to the eyelids, such as from a bug bite or cat scratch. After a minor injury, bacteria can enter the wound and cause an infection.

The bacteria that most commonly cause this condition are:

The condition is more common in children than adults because children are at higher risk for infection with the type of bacteria that causes this condition.

The main treatment for preseptal cellulitis is a course of antibiotics given orally or intravenously (into a vein).

The type of antibiotics may depend on your age and if your healthcare provider is able to identify the type of bacteria that’s causing the infection.

Preseptal cellulitis in adults

Adults will usually receive oral antibiotics outside of the hospital. If you don’t respond to the antibiotics or the infection gets worse, you may need to go back to the hospital and receive intravenous antibiotics.

Antibiotic medications used in the treatment of preseptal cellulitis in adults include the following:

  • amoxicillin/clavulanate
  • clindamycin
  • doxycycline
  • trimethoprim
  • piperacillin/tazobactam
  • cefuroxime
  • ceftriaxone

Your healthcare provider will create a treatment plan based on your healthcare needs.

Pediatric preseptal cellulitis

Children younger than 1 year will need to have IV antibiotics given in a hospital. IV antibiotics are usually given through a vein in the arm.

Once the antibiotics start working, they can go home. At home, oral antibiotics are continued for several more days.

Medications used in the treatment of preseptal cellulitis in children include the following:

  • amoxicillin/clavulanate
  • clindamycin
  • doxycycline
  • trimethoprim
  • piperacillin/tazobactam
  • cefuroxime
  • ceftriaxone

Healthcare providers create treatment plans outlining dosage and how often the medication is administered based on the child’s age.

If you have any of the symptoms of preseptal cellulitis, like redness and swelling of the eye, you should see a healthcare provider right away. Early diagnosis and treatment is essential for preventing complications.

An ophthalmologist or optometrist (both eye doctors) will likely do a physical examination of the eye.

After checking for signs of an infection, like redness, swelling, and pain, they may order other tests.

This may involve requesting a blood sample or a sample of discharge from the eye. The samples are analyzed in a laboratory to find out what kind of bacterium is causing the infection.

The eye doctor may also order imaging tests, such as an MRI or CT scan, so they can see how far the infection has spread.

Preseptal cellulitis is an infection of the eyelid typically caused by bacteria. The main symptoms are redness and swelling of the eyelid, and sometimes a low fever.

Preseptal cellulitis is usually not serious when treated right away. It can clear up quickly with antibiotics.

However, if left untreated, it can lead to a more serious condition called orbital cellulitis.