The Potential Therapeutic Effect of Green Tea in Treatment of Vernal Keratoconjunctivitis

Vernal keratoconjunctivitis is a chronic, recurrent and severe ocular allergic disease, which is characterized by persistent allergic inflammation of the conjunctiva. It can be accompanied by ocular discomfort and visual disturbance. All forms are characterized by intense itching, tearing, mucous secretions and a severe photophobia, which often forces children to live virtually in dark places. Conjunctival proliferative changes, such as the formation of giant papillae are the characteristic findings of affected individuals. Giant papillae develop as a result of infiltration of inflammatory cells, changes in the epithelial layer, and increased deposition of extracellular matrix molecules such as collagen and proliferation of conjunctival fibroblasts. Currently several therapeutic options such as corticosteroids, mast cell stabilizers and cyclosporine are applied for treatment of Vernal keratoconjunctivitis, but in long-term, the chronic and recurrent nature of this problem leads to failure or appearance of side effects of current treatment in many patients. Recently, Green tea extract and its principal active ingredient, epigallocatechin gallate, are gaining attention and increased usage due to its healthful properties. It has considerable anticatactogenic effect by inducing apoptosis in lens epithelial cells and antioxidant effects. Also its great benefits were achieved in attenuation of damaging influences to the retina caused by ischemia/reperfusion. Based on evidences supported beneficial effects of green tea, we hypothesize that local administration of green tea and its extract seems to be a proper substitute or adjunct to current treatments of Vernal keratoconjunctivitis. This plant contains a series of antioxidants that can abolish the process of allergic cascade. Moreover, by suppressing TNF-alpha potentially, it can reduce proinflammatory reaction, as well as fibroblast proliferation and subsequently decrease giant papilla formation; however, its potency should be evaluated in multiple clinical trial studies.