The case of a patient 53 years old that had a picture of cortical impairment and pyramidal disfunction, leading in 6 months to acinetic mutism is reported. The histopathology lead to the diagnostic of Creutzeldt-Jakob disease, with neuronal loss, gliosis and status spongiosus. The electron-microscopic examination showed that the status spongiosus was due to cellular processes, some having vesicular bodies sugestive of pre-synaptic vesicles.