An Unusual Case of Herpes Simplex Viral Encephalitis Following Acute Retinal Necrosis after Administration of a Systemic Steroid
A 57-year-old man was referred to Samsung Medical Center with abrupt confusion, fever, and loss of vision in both eyes. The patient was in his usual state of health until two weeks prior, when he began to develop sudden loss of vision in his right eye. In another hospital, he was diagnosed with retinal vasculitis in his right eye and was prescribed oral prednisolone, 60 mg/day for three days, followed by 120 mg/day for three days. The retinal vasculitis did not respond to oral prednisolone, so he was treated with intravenous methylprednisolone, 1 g/day for five days. Two days after initiation of intravenous methylprednisolone, he complained of decreased vision in his left eye. One week after initiation of intravenous methylprednisolone, he became drowsy and high fever occurred, and he was then referred to Samsung Medical Center. On neurological examination, he was drowsy and confused to time and place orientation. Mini-mental status examination was 18. He consistently complained of severe headache and bilateral ocular pain. However, his extraocular movement did not show any limitation in all directions. Neck stiffness and meningeal irritation sign were not definite. Other focal neurologic deficits were not found.\nHis brain magnetic resonance imaging (MRI) showed a hyper-intense lesion in the left medial temporal and bilateral medial occipital areas on T2-weight images, suggestive of HSE (). Cerebrospinal fluid (CSF) study revealed 11 cells/mL (lymphocytes 90%), low protein (19.3 mg/dL), and normal range glucose concentration (63 mg/dL compared to 110 mg/dL in serum). An empirical antiviral agent (acyclovir 30 mg/kg/d) was administered intravenously. One week later PCR of the CSF was revealed to be positive for HSV-1 DNA. On the night of admission, the patient experienced a generalized tonic-clonic seizure during sleep. His electroencephalography showed sharp waves in left or right anterior temporal areas (F7T7, F8T8 maximum) with a frequency of 1/min and diffuse slow waves. An antiepileptic drug (phenytoin 300 mg/d) was administered and no more epileptic seizure recurred.\nOn the day of admission, his visual acuity was perception of light in both eyes. Fundus examination showed retinal hemorrhage, confluent retinal necrosis affecting almost the whole retina, vascular sheathing involving both arterioles and venules, optic disc swelling, and exudative retinal detachment in both eyes (). Fluorescein angiography revealed multiple vascular occlusions and vascular leakage. Ultrasonography shows retinal detachment in both eyes (). Infectious retinitis including acute retinal necrosis was suspected, but in terms of the location of necrosis, his clinical features were not typical of ARN Diagnostic vitrectomy confirmed the presence of HSV-1. Finally, he was diagnosed with ARN with optic neuropathy by HSV-1.\nAfter administration of intravenous acyclovir for 14 days, his systemic symptoms consistent with encephalitis slowly resolved, but his vision was not restored. On follow-up examination, retinal necrosis did not progress, but he still suffered from severe bilateral ocular pain with partial improvement of the exudative retinal detachment (). Thus, intravitreal ganciclovir injection (5,000/0.05 μg/mL) causes pain relief and decreased intraocular inflammation. But his visual acuity could not perceptany light. Bilateral rhegmatogenous retinal detachment with optic atrophy was found six weeks later, thus vitrectomy with silicone oil tamponade was done in the right eye.