MCQ – 84546

Correct Answer � D Explanation

• Phlyctenular keratoconjunctivitis,is an inflammatory syndrome caused by a delayed type-IV hypersensitivity reaction to one or more antigens.
• The triggering antigen is usually a bacterial protein (most common – Staphylococcus aureus).
• These usually manifest as small raised nodules, pinkish-white or yellow in color, which may ulcerate (or, more rarely, necrose) and are often surrounded by dilated blood vessels. 
• Corneal lesions are usually triangular in shape, with the base at the limbus and the apex pointing towards the center of the cornea.

• Characterized by the following:
  o Phlycten
  o May eventually form ring ulcers
  o Scrofulous ulcer: shallow marginal ulcer due to the breakdown of limbal phlycten
  o Fascicular ulcer has a prominent parallel leash of blood vessels. It heals leaving a band-shaped opacity.

Treatment:

• Topical steroids; atropine if the cornea is involved.