Which of the following is NOT a typical cause of preseptal cellulitis?

• A. Skin trauma from insect bite
• B. Internal hordeolum
• C. Middle ear infection
• D. Contact lens misuse

Answer: (D)

Preseptal cellulitis is an infection of the eyelid tissues located in front of the orbital septum, so it typically arises from bacteria entering through a break in the eyelid skin or from a localized eyelid infection. A skin trauma from an insect bite breaks the barrier and allows bacteria to invade the eyelid tissues, leading to cellulitis. An internal hordeolum, an infection at the eyelid margin, can spread locally to the surrounding eyelid tissues and cause preseptal cellulitis. A middle ear infection is not a common direct source for eyelid infection, since it lies farther from the eyelid structures and doesn’t usually extend to the eyelid in the typical pattern. Contact lens misuse tends to produce surface eye problems like keratitis or conjunctivitis rather than primary infection of the eyelid tissues, so it’s not a typical cause of preseptal cellulitis.