Anterior bilateral optic neuritis as a complication of Varicella-Zoster virus (VZV)

Abstract

Aims/Purpose: To shed light on optic neuritis as a potential ocular complication of Varicella-Zoster virus (VZV) infection.

Methods: Presentation of a clinical case.

Results: We present the case of a 70-year-old woman, who arrived at the Emergency Room complaining of a bilateral acute loss of visual acuity. She had received treatment on several occasions for a recurring zoster involving the left V2 territory, the last episode being one month before her visit. She had a visual acuity of 0.3 on her right eye, and 0.6 on her left eye. Pupil examination evidenced a relative afferent pupillary defect (RAPD) on her right eye. Dyschromatopsia was documented by red desaturation and Ishihara tests. Fundus examination displayed an asymmetrical bilateral papillitis, predominant in her right eye. This finding was confirmed by an Optic Coherence Tomography (OCT). A cranial CT scan and a general blood analysis were performed, and both returned normal results. The patient was admitted to the Hospital to start treatment with intravenous steroids. Additional tests were performed, including blood serological tests, a temporal artery Doppler ultrasound, a cranial MRI, and a lumbar puncture. Blood serological tests showed positive high titles of IgG VZV, and came back negative for IgM VZV. Lastly, the polymerase chain reaction (PCR) test on the CSF sample turned out positive for VZV, shedding light on the diagnosis. Steroids were suspended and the patient was started on intravenous Acyclovir. Clinical evolution was favorable, and her visual acuity on the 2-month follow-up visit had climbed up to 0.6 on her right eye and 0.7 on her left eye.

Conclusions: This case illustrates the relevance of ruling out infectious causes of optic neuritis, specifically VZV, in patients in which other causes are less likely, those who present a bad evolution on inflammatory treatment, or who have a recent episode of VZV infection. MRI demyelination is a frequent finding in both demyelinating and infectious diseases, therefore not ruling out the latter. Positive blood serology indicates previous contact with VZV, but has little sensibility for detecting an active infection. All these reasons justify the need to select patient who may benefit of a lumbar puncture, as an early diagnosis radically changes the therapeutical approach.