Use of cyclosporine A and tacrolimus in treatment of vernal keratoconjunctivitis.

Vernal keratoconjunctivitis is a sight-threatening inflammatory disease of conjunctiva and cornea. It is frequently observed in young children with the onset usually occurring in the first decade of life. Mild cases of VKC tend to remit with nonspecific and supportive therapy. In contrast, severe cases are usually more protracted with remission/relapse occurring for a prolonged period of time. Although VKC is classified as an allergic eye condition, the role of allergens as an inciting factor is not clear. Pathogenesis of VKC involves roles for IgE, cytokines, chemokines, and inflammatory cells (T and B lymphocytes, mast cells, basophils, neutrophils, and eosinophils) with the release of their granular proteins, proliferation of fibroblasts, and laying down exuberant amounts of collagen fibers in the conjunctival tissue. In severe VKC cases-often of tarsal VKC-diagnostic giant papilla are classically observed on the upper tarsal plate, giving the classic 'cobble-stone' appearance. Corneal ulcer can occur from the effect of eosinophilic granular proteins on corneal epithelium and by physical trauma by intense eye rubbing. Topical corticosteroids, often required for controlling symptoms and signs in severe VKC, can lead to serious ocular complications. Immunomodulators that have been investigated for VKC treatment include topical ocular preparations of cyclosporine A and tacrolimus. Severe VKC responds promptly to topical cyclosporine A and tacrolimus, mostly within 1 month of therapy. Prolonged use of cyclosporine A and tacrolimus in VKC is safe and is tolerated by most patients without significant side effects. Recent investigations on the use of these two agents in VKC are the main purpose of this review. The use of cyclosporine A and tacrolimus are a major breakthrough in treatment for severe VKC, a debilitating allergic eye disease in children.