ACUTE BILATERAL RETINAL NECROSIS - HEALIN G OF THE 2ND AFFECTED EYE

Background The acute retinal necrosis syndrome (ARN) is caused by the Varicella zoster virus or the Herpes simplex virus. However the dosage and duration of the antiviral therapy for prevention of an infection in the second eye or treatment of an infection on an affected fellow e ye is still not known. We discuss the timing of a possible steroid tre atment and demonstrate in a case report how an acute retinal necrosis syndrome in a fellow eye was successfully treated. Patient First eye. A 27-year-old not immunocompromised patient (HIV-negative) showed 2 mo nths after a febril state an acute iritis in the right eye. 14 days la ter an acute retinal necrosis syndrome was observed. The patient recei ved Acyclovir 3 x 750 mg i.v. for 6 days, and afterwards 5 x 200 mg or ally for 5 days. The patient developed an inoperable retinal detachmen t despite therapy. Second eye. Eight days later the fellow eye develop ed a localized retinal necrosis. Varizella zoster DNA was found in the aqueous humor using the polymerase chain reaction (PCR). The antivira l therapy with Acyclovir was increased from 1.1 g q 12 h (2 x 15 mg/kg /d) to 1.0 g q 8 h (3 x 12.5 mg/kg/d). After 4 weeks the i.v. therapy was followed by an oral therapy of 5 x 800 mg for 12 weeks. This dosag e was reduced to 5 x 400 mg for another 12 weeks. The oral therapy wit h corticosteroids started on the 11th day with 100 mg Prednisone, in s lowly reducing dosage during 18 weeks. The fellow eye recovered fully with a visual acuity of 20/20 after 6 months. Conclusion The disease s tarted in the fellow eye with an acute iritis and a secundary glaucoma . These symptoms can be a characteristic prodroma of an acute retinal necrosis syndrome caused by a varizella zoster- or Herpes simplex viru s infection, which was not recognized first. Whether a long-term thera py (as described above) is necessary or not is unclear on the basis of a single case report, but we currently recommend the high-dose treatm ent regimen until further data emerge.