The diagnosis of prion diseases is always clinical. It is usu-ally confirmed by the histopathology of the brain tissue showing characteristic histological changes. No serological tests are available, as prions are inert agents and do not elicit any immune response in infected hosts. The prions cannot be detected in the infected tissue by any method including the electron microscopy, antigen detection, and genomic methods, such as DNA probe or polymerase chain reaction (PCR).
Detection of protein 14–3–3 in the CSF by Western blot is a sensitive and specific method in cases of sporadic CJD and in vCJD. A specific reduction in uric acid level in the CSF has been shown in vCJD but not in sporadic CJD, thus facilitating in the differential diagnosis of vCJD.
No specific treatment is available for any prion disease.
Prevention and Control
Prions are highly resistant to inactivation by disinfectants used for other viruses, such as formaldehyde, detergents, and ionizing radiations. Hence, the materials from patients with CJD or vCJD must be handled with special care. For prevention of these diseases, special disinfection protocols have been developed by the World Health Organisation (WHO). These include auto-claving at 15 lbs for 1 hour (instead of 20 minutes) or treatment with 0.1 M sodium hydroxide and 5% hypochlorite solution.
Since cases of blood transfusion-associated CJD have been reported, it is a matter of great concern. However, currently no method including PCR is available for demonstration of the agent in the blood.