Creutzfeldt- Jakob Disease
The Common Vein Copyright 2010
Definition
Creutzfeldt-Jakob disease, or mad cow disease, belongs to a group of neurodegenerative diseases called Human Transmissible Spongiform Encephalopathies.
It is caused by prions, which are proteins that are resistant to proteases, to disinfection and sterilization, and to ionizing radiation. The hypothesis is that it is an altered form of an intraneural protein that lost its normal function, and that also acquired the capacity of transforming normal ones into pathological ones. These prions can be transmitted through contaminated products (corneal grafts, dural grafts, harvested human growth hormone), or inherited (mutation in PrP gene). It is also possible that ingestion of animals with the disease is a transmission pathway.
The lesion that characterizes these diseases is neurodegeneration with vacuolation of brain tissue, which may acquire spongy character in microscopic examination.
Clinically, it is characterized by rapidly progressive dementia, usually leading to death in about a year after the onset of symptoms. These are the presence of cognitive impairment, focal symptoms, behavioral disturbances, cerebellar ataxia, pyramidal signs, visual disturbances and myoclonus. The most common affected age ranges in the range of 45 to 75 years. It has a very low incidence, of about 1-1.5 cases per million a year.
The final diagnosis is made by pathologic study of brain tissue to observe the typical changes. Identification of the prion protein is currently the most reliable diagnostic marker, which can be detected by Western blot techniques, having the disadvantage of requiring fresh brain tissue however. An important test is the determination in the CSF of levels of 14-3-3 protein, a marker of neuronal damage, characteristically with CSF concentration increased in CJD. The EEG is also often useful, typically showing complex and slow sharp waves.
CT and MRI are useful to exclude other causes of subacute neurological disease. In MRI, hyperintense signals in FLAIR and DWI are seen in the basal ganglia, more intensely in the pulvinar nuclei of the thalamus, and diffusely in the cerebral cortex.
Currently, there is no treatment or even therapy for symptom control. It carries a 100% mortality.