[A probable case of Creutzfeldt-Jakob disease with electroretinogram alterations]

Although visual disturbance is recognized as a clinical feature of Creutzfeldt-Jakob disease (CJD), lesions within the retina have to date, recorded little attention. In this single case study, we report a case of retinopathy observed in a 72-year-old female patient with CJD. The patient admitted to the hospital complaining of a 2-month history of visual disturbance, dysarthria, and gait disorder. Electroencephalogram showed periodic synchronous discharges synchronizing with myoclonic jerks. Electroretinogram (ERG) using single bright flash in a dark-adapted state demonstrated the absence of b-wave in both eyes. One month later, ERG could no longer record a-wave of the right eye. The absence of b-wave on ERG indicated a disorder within the inner layer of the retina, furthermore lesions detected in the occipital lobe were considered too mild to have elicited such visual disorder. We further conclude that retinopathy may be found in CJD and can progress in retrograde from ganglion cells to photoreceptors. Although the frequency of retinopathy among the CJD population is unclear, detailed clinical observation and analysis of ERG in patients with visual disorders of unknown cause is extremely important for both the screening and exclusion of CJD.