Observation on the Herpes Simplex Keratitis

Viral keratitis has now become the highest incidence and the most severe-caused blindness corneal disease in the worldwide, as is superior to bacterial keratitis and fungal keratitis. At present, clinical treatments mainly depend on local and systematic use of antiviral drugs for viral keratitis, which can inhibit replication of viruses in corneal tissues and directly damage viral action. However, basal studies for viral keratitis have suggested that pathological immune injury produced by the body also play an important role in the formation of corneal ulcer, the damage of visual function in patients, during the necrotic stromal inflammation phase, endotheliitis phase and even serious combination of iridocyclitis phase of viral keratitis. There is, however, a larger controversy in the hormone therapy for this disease clearly caused by pathological immune injury in medical world. Patients with infectious keratitis caused by viral infection, who receive hormone treatment, may cause viral replication enhanced and out of control, and hormone itself could also cause spontaneous corneal tissues fusion; hence, treatments combined with hormone have a certain risks. In clinical treatments, permanent corneal opacity caused by corneal inflammation responses will cause patients permanent visual acuity loss, after patients' corneal lesions were controlled with simple use of antiviral drugs. Another important reason is the high incidence of blindness caused by viral keratitis: herpesvirus, such as herpes simplex virus and herpes zoster virus, will involve trigeminal ganglia and hide after primary infection, and will repeatedly recur under the stimulation of excessive drinking, menstruation, taking a cold and operation etc.. Viral keratitis often does not cause patients severe visual impairment at initial onset. But, viruses in patients with herpes simplex virus keratitis show extremely high recurrence rates. As suggested in epidemiologic studies in the Euro-American countries, its recurrence rate could be up to 30% in the first year, and 46% in the second years. In most cases, transparent corneal tissues develop nephelium and even macular nebula opacities after repeated recurring, and patients eventually lose visual acuity, becoming people with blindness and disabilities. Nonsteroidal antiinflammatory drugs, such as pranoprofen and bromfenac sodium, show significant inhibition of virus recurrence and relief of corneal inflammation responses in experiments in vitro and animal experiments, which indicated in previous studies. In clinical, local application of nonsteroidal antiinflammatory drugs does not result in spontaneous corneal tissue fusion, drug-induced glaucoma, drug-induced cataract and other risks. In order to seek more effective clinical treatments for viral keratitis patients in terms of controlling inflammation injury, preserving visual functions and reducing virus recurrence, this study observed that pranoprofen, a nonsteroidal antiinflammatory drug, inhibits pathological immune injury of viral keratitis and prevents this disease recurring, according to the basal research background of viral keratitis.