Vernal Keratoconjunctivitis (VKC)

Abstract

Vernal keratoconjunctivitis (VKC) is an allergic ocular disease in children and young adults. It is linked to atopy but it is characterized by typical inflammatory changes of ocular tissues. The conjunctiva often shows hyperplasia, with infiltration of lymphocytes and eosinophils; also mast cells, confined to the substantia propria in normal subjects, invade the epithelium in VKC. Both mucosal (MC_T) and connective tissue (MC_TC) types of mast cell can be found in the conjunctival tissues of VKC patients, whereas MC_TC predominate in the normal eye. Much of the damage caused to the surface of the eye in VKC appears to be due to cytotoxic factors released from the invading eosinophils. Ongoing studies of cell/mediator interactions involved in the inflammatory process are contributing to the understanding of VKC and other allergic eye diseases also providing the rationale for effective treatment which may be found by blocking the immunological inflammatory network at specific points. Therapeutic studies with nedocromil sodium have shown encouraging results. For example, a six-week placebo comparison in Italy found nedocromil sodium eye drops to be efficacious in reducing hyperaemia, eye itching and inflammatory cells present in tears. Similarly, a four-week trial in Egypt showed this drug superior to sodium cromoglycate using the same q.i.d. regimen.

Key Words:

• vernal keratoconjunctivitis
• ocular allergy
• inflammatory cell
• ocular inflammation
• nedocromil sodium