Rapidly progressive dementia with visual manifestations and myoclonus: a case report suggestive of Creutzfeldt-Jakob disease

Abstract

Case Presentation: A 61-year-old female patient with a history of hypothyroidism presented with a clinical picture that began approximately 20 days earlier with decreased visual acuity, progressing to visual hallucinations, mental confusion, and behavioral changes. After about eight days, she developed difficulty walking and feeding, with rapid loss of functional autonomy, becoming bedridden and dependent for basic activities, later evolving with myoclonus. Upon hospital admission, she presented with a rapidly progressive dementia syndrome. Neurological examination revealed decreased level of consciousness without evident focal deficits, normoreflexia, and negative plantar cutaneous and Hoffman reflexes. Valproic acid was prescribed at a dose of 1500 mg per day for symptomatic control. Brain magnetic resonance imaging showed an area of cortical hyperintensity with diffusion restriction in the right parietal region, later demonstrating cortical hyperintensities in bilateral temporo-parieto-occipital regions. Cerebrospinal fluid analysis showed no infectious or inflammatory findings but revealed the presence of the 14-3-3 protein. Electroencephalography demonstrated generalized periodic high-amplitude sharp wave complexes with intervals of approximately 1 to 1.2 seconds throughout the recording. During hospitalization, there was progressive neurological deterioration, with further reduction in the level of consciousness and the need for intensive care, maintaining a clinical picture compatible with rapidly progressive dementia and a strong clinical suspicion of Creutzfeldt-Jakob disease. Discussion: Creutzfeldt-Jakob disease is a rare prion encephalopathy characterized by rapidly progressive cognitive decline associated with neurological manifestations such as myoclonus, visual disturbances, and extrapyramidal signs. Among the described presentations, the Heidenhain variant is notable, in which visual manifestations constitute the predominant initial symptom. In the present case, reduced visual acuity and visual hallucinations preceded cognitive and motor impairment, establishing a clinical pattern compatible with this variant. Magnetic resonance imaging findings of cortical hyperintensity in parieto-occipital regions, the electroencephalographic pattern of generalized periodic discharges, and the presence of the 14-3-3 protein in the cerebrospinal fluid reinforce the diagnostic suspicion in the context of rapidly progressive dementia. Final Comments: This case highlights the importance of considering prion diseases in the investigation of rapidly progressive dementia syndromes, especially when visual manifestations precede global cognitive impairment. The association between a typical clinical presentation, characteristic magnetic resonance imaging findings, a compatible electroencephalographic pattern, and the presence of the 14-3-3 protein in cerebrospinal fluid significantly contributes to diagnostic suspicion.