Measurement of brain-specific proteins in the CSF, such as protein 14-3-3, neuron-specific enolase (NSE), S-100b, and tau protein, is supportive. Detection of protein 14-3-3 is a reliable and sensitive marker for sporadic Creutzfeldt-Jakob disease, with a sensitivity and specificity approaching 96%. In vCJD, on the other hand, sensitivity of 14-3-3 protein is 50% and specificity is 91%, while sensitivity of CSF tau protein is 80% and specificity is 94%. A combined determination of 14-3-3 and tau, S100b, or NSE increases the sensitivity to over 93%. Unfortunately, these tests usually take weeks to return, which limits their immediate clinical utility. A multivariate analysis revealed that the sensitivity of all tests was greatest in patients with homozygosity at codon 129 of the prion protein gene, a short disease duration, and age at onset older than 40 years. A repeat lumbar puncture increased the diagnostic sensitivity.[3,4,6]
Prions are highly resistant to inactivation. Dry heat (320° F [160° C] for 24 hours), formaldehyde sterilization, and standard steam sterilization do not sterilize prion-contaminated items. CNS tissue contains the highest titer of PrP and should be handled with the greatest care. Other body tissues/fluids are much less likely to pose a risk for infection with Creutzfeldt-Jakob disease. Because prions are not inactivated by formalin, brain tissue samples that have been formalin-fixed should be immersed in 100% formic acid for 1 hour for disinfection. Disposable instruments should be used whenever possible.
The guidelines for reprocessing instruments vary in different countries as a result of scientific uncertainties. Surfaces that have been in contact with prion material should be decontaminated with > 5.25% solution of sodium hypochlorite or 1 N sodium hydroxide for 1 hour. Potentially contaminated waste should be autoclaved at 273-279° F (134-137° C) for 20 minutes and then incinerated. vCJD is highly lymphotropic, has been reported to spread by nonleukodepleted blood transfusion, and is present in high titers in lymphatic tissue, the tonsils, and the spleen. The diagnosis of vCJD is routinely made from histopathologic analysis of brain biopsy tissue; however; tonsillar biopsy can potentially establish the diagnosis of vCJD.
Although several drugs have been used against Creutzfeldt-Jakob disease (such as quinacrine, chlorpromazine, and D-penicillamine), no effective treatment has been discovered. Usually, a trial of high-dose intravenous steroids is initially administered, to treat potential steroid-responsive encephalopathy, which mimics Creutzfeldt-Jakob disease.
The patient in this case was treated with supportive care, and sodium valproate was used for her myoclonic jerks. At the request of the family, a trial of chlorpromazine—and, later, quinacrine—was given. She developed jaundice and abnormal liver function tests and so the quinacrine was discontinued. She has been cared for at home for the past year, with family members taking all precautions while handling her. On a recent follow-up visit, the patient was bedridden, in a vegetative state, and required enteral feeding and constant nursing care.
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Cite this: Sridharan Ramaratnam. A 60-Year-Old Woman With Worsening Neuropsychiatric Symptoms - Medscape - Aug 12, 2015.