CREUTZFELDT-JAKOB DISEASE (CJD) - Adult

Creutzfeldt-Jakob disease (CJD) is a rare, rapidly progressive, invariably fatal brain disorder primarily characterized by mental deterioration, although motor problems can be significant in many cases. CJD belongs to a group of human and animal diseases known as transmissible spongiform encephalopathies (TSE) or prion diseases. Spongiform refers to the characteristic appearance of infected brains, which become filled with holes until they resemble sponges under a microscope. Typically, onset of symptoms occurs at about age 60 and runs a rapid course. There are four major categories of CJD: sporadic CJD, hereditary CJD, acquired or iatrogenic CJD, and variant CJD.

Sporadic CJD is the most common form of the disease. It accounts for 85% of cases. The cause of sporadic CJD is unknown, but it is believed that a normal cellular protein undergoes a spontaneous change in conformation (prion protein) that results in the disease. This form of the disease is believed to be spontaneous and not the result of an infection.

Hereditary or familial CJD is a very uncommon disease and the consequence of a mutation in the gene that encodes the prion protein. About 5 to 10 percent of cases of CJD in the United States are hereditary.

Acquired or Iatrogenic CJD is also very rare accounting for less than 1% of cases. It results from the accidental transmission during the course of medical interventions. Examples include transmission in cases of corneal transplantation, dural grafts, or treatment with Human Growth Hormone isolated from cadaveric pituitary glands.

Diagnostic testing:

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  Electroencephalography (EEG);

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  Magnetic resonance imaging (MRI) of the brain;

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  Cerebrospinal fluid analysis for 14-3-3 protein;

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  Tonsil biopsy is helpful in the diagnosis of variant CJD, but less so in other forms of the disease; and

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  Brain biopsy.

Brain biopsy is the definite diagnostic test, but is performed only in selected cases because the procedure may be dangerous to the individual. Since a correct diagnosis of CJD does not help the individual, brain biopsy is discouraged unless it is needed to rule out a treatable disorder.

Physical findings:

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  Rapidly progressing dementia with myoclonus (twitching);

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  Problems with muscle coordination;

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  Personality changes (impaired memory, judgement, and thinking);

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  Impaired vision;

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  Insomnia; and

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  Depression.

ICD-9: 046.19

About 90 percent of patients die within 1 year. In the early stages of disease, patients may have failing memory, behavioral changes, lack of coordination and visual disturbances. As the illness progresses, mental deterioration becomes pronounced and involuntary movements, blindness, weakness of extremities, and coma may occur.

There is no treatment that can cure or control CJD. Current treatment is aimed at alleviating symptoms and making the patient as comfortable as possible. Opiate drugs can help relieve pain, and the drugs clonazepam and sodium valproate may help relieve involuntary muscle jerks.

SUGGESTED PROGRAMMATIC ASSESSMENT*

Suggested MER for Evaluation:

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  Clinical notes and results of neurological examination that establish the presence of rapidly progressive dementia or neurodegenerative illness; and

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  If available, ancillary studies, including spinal tap, cerebrospinal fluid analysis, detection of 14-3-3 protein in spinal fluid, EEG, and brain biopsy are helpful as supportive evidence.

Suggested Listings for Evaluation:

REMARKS