Skip to main content

Starting at 12:01 a.m. PT Sunday, some AAO.org products and services may be unavailable as we make website improvements. We expect to complete the work by late Sunday evening.

  • Can you tell me about phlyctenular keratoconjunctivitis?


    Question:

    I was diagnosed with phlyctenular keratitis, and I didn’t fully understand when my ophthalmologist told me about the condition. Could you briefly define it?


    Answer:

    Phlyctenular keratoconjunctivitis is a type of inflammation (swelling/redness) of the cornea or conjunctiva involving the front of the eye.  It is thought to be a delayed allergic reaction of the immune system when someone is re-exposed to a virus or bacteria. Most commonly, the phlyctenules are caused by an intense immune reaction to a protein in the bacteria Staphylococcus. This bacteria is commonly found on the eyelids and front surface of the eye. Where normally the second exposure is milder than the first, with this condition it is usually seen as a raised lump(s) in the cornea or conjunctiva with intense redness from dilated blood vessels. Symptoms range from mild irritation to intense pain, decreased vision, and light sensitivity.

    The "phlyctenules" are usually treated with topical steroids and antibiotics.


    Answered By: