Creutzfeldt-Jakob Disease: Correlation of Clinical Neuroradiological Aspects and Detection of 14.3.3. Protein in Cerebrospinal Fluid

Abstract

Creutzfeldt-Jakob disease (CJD) is a rare, transmissible illness that usually affects older adults and is characterised by rapidly progressive dementia, ataxia, myoclonus and various other neurological defects. This is now thought to be a chronic infections disease caused by an agent called a prion. The prions differ from viruses because contain little or no nucleic acid and evoke no immune response. CJD is a progressive, inevitably fatal disease with a mean survival time of 6 months to 1 year.

Diagnosis is usually made clinically and electroencephalographically but even now, the diagnosis can only be confirmed by brain biopsy. CT scans usually show either no abnormalities (80% of cases) or non specific atrophy. Recently there have been reports of characteristic findings on MR images. Bilateral, symmetrically increased signal intensity was demonstrated in the basal ganglia but in various patients this finding was absent. Recently, diffusion weighted MR images proved to be useful in the evaluation of CJD but these studies must be confirmed with additional patients. The biomedical analysis of cerebrospinal fluid that identifies 14.3.3. protein in a patient with dementia was positive in 96% of cases.

The presence of 14.3.3. protein in cerebrospinal fluid may be due to massive neuronal disruption and to the leakage of brain proteins into cerebrospinal fluid. Also if this protein could sometimes be found in patients with acute viral encephalitis, strokes (within one month before testing), subarachnoid haemorrhage or Rett's syndrome, CJD could not reasonably be included in the differential diagnosis of any of these disorders. We describe three cases of CJD. In two patients the typical MRI images of hyperintensity on T2-weighted images of the basal ganglia were observed. In all three patients 14.3.3. protein was found in the cerebrospinal fluid. Therefore, the association of a clinical diagnosis of dementia, MR imaging and a positive test of 14.3.3. protein in the cerebrospinal fluid strongly supports the diagnosis of CJD without the need for cerebral biopsy. Biopsy could be reserved only for doubtful cases.