Variant Creutzfeldt-Jakob disease

摘要

Surveillance of Creutzfeldt-Jakob disease (CJD) was re-established in 1990 in the UK in order to identify any changes in the incidence or characteristics of human prion diseases that might be the consequence of human exposure to the bovine spongiform encephalopathy (BSE) agent. The subsequent identification of a novel human prion disease in the UK, variant Creutzfeldt-Jakob disease (vCJD) in 1996 was based on detailed neuropathological and clinical findings in a series of 10 patients (Will et al, 1996). One hundred and six cases of vCJD have so far been identified in the UK, with three cases in France and one in Ireland. The clinical features of variant CJD differ from those in sporadic CJD: patients present with psychiatric features or sensory abnormalities, followed by ataxia and other movement disorders. Dementia usually occurs at a late stage in the disease. The age at death is much younger than in sporadic CJD (median 28 years, range 14-74) and the duration of the illness is prolonged (median 13 months, range 6-39). The electroencephalogram in variant CJD shows no specific abnormalities. Magnetic resonance imaging of the brain in variant CJD has demonstrated an area of high signal intensity in the pulvinar (within the posterior thalamus), which has proved to be useful diagnostic investigation. This abnormality is related to the intense gliosis and neuronal loss in this region of the brain on histological examination. All cases of vCJD have occurred in individuals who were homozygous for methionine at codon 129 in the prion protein gene.