Abstract
Herpes simplex virus (HSV) is the most common cause of acute viral encephalitis. Acute retinal necrosis (ARN) is a rapidly progressing and potentially blinding eye disease that may be induced by HSV. The present case study reports the very rare case of a patient with herpes simplex encephalitis (HSE) combined with acute retinal necrosis (ARN). A 47-year-old woman was admitted to hospital with persistent high fever and somnolence for 5 days. Magnetic resonance imaging showed abnormal signals in the right medial temporal lobes, and HSV-1 was identified in the serum and cerebrospinal fluid. Five days later, despite treatment with intravenous acyclovir and partial improvement in consciousness, the patient suddenly developed blurred vision and bilateral visual pain. Fundus fluorescence angiography revealed bilateral vessel obstruction and flaky reduced fluorescence. ARN was diagnosed clinically. Dexamethasone was administered as an anti-inflammatory adjunct to intravenous acyclovir therapy. The visual acuity of the patient was reduced to mere light perception a further 4 days later. The present case indicates that HSE may be complicated with ARN, causing a reduction in visual acuity to mere light perception within a very short time.