Slow Infections of CNS

Question 0

Progressive multifocal leukoencephalopathy

PML

Answer 0

-rare, fatal demyelinating disease of CNS
-caused by *JC virus, infects then kills oligodendroglia
-immunosuppressed adults, esp. AIDS
-transmitted through saliva, latent in kidneys
Symptoms
-impaired memory, confusion, disorientation
-hemiparesis, visual disturbances, incoordination, and seizures
Tx
-reconstitution of the immune system

Question 1

Subacute sclerosing panencephalitis

SSPE

Answer 1

-slow infections caused by *measles virus
-fatal, progressive degenerative disease of CNS
Symptoms
-mild changes in personality
-generalized convulsions, dementia, death
Diagnostic
-Measles antibody in CSF
-Electroencephalography
-brain biopsy
Tx
-no proven therapy

Question 2

varient Creutzfeldt-Jakob disease (vCJD)

Answer 2

-caused by eating brain-contaminated beef from cows with bovine spongiform encephalopathy (BSE) in cows
Path
-caused by chains of misfolded PrPsc proteins
Tx
-none
Prevention
-avoidance
-leuko-depletion to reduce levels of infectivity in blood

Question 3

Neurosyphilis

Answer 3

-caused by Treponema pallidum, a spirochete
-strict human pathogen
-transmitted b sexual contact or congenitally
Diagnostic
-dark field microscopy, special staining, or immunofluorescence
-no culture methods
-sensitive to drying, disinfectants, and heat as low as 42 C
Path
-primary - chancre on balls
-secondary - lymphadenopathy, rash on palms and soles
-tertiary - pralytic dementia, aortic aneurysm, aortic insufficiency, tabes dorsalis, gummas
Symptoms
- initially forgetfulness and personality change
- progress to deficits in memory and judgment leading to severe dementia
-sensory ataxia and *lancinating pains (“lighting pains”)
Tx
-penicillin therapy
-No vaccines

Question 4

Rabies

Answer 4

-acute, progressive encephalitis w/ no proven effective cure
Transmission
-contact w/ saliva or brain/nervous system tissue of infected animal
-usually bite wound!
-rare route through open cuts or corneal and organ transplantations
Reservoirs
-cats, dogs, cattle
-vampire bats!
-pretty much all mammals
Symptoms
-initially, fever, HA, general weakness and discomfort
-later, insomina, anxiety, confusion, paralysis, hallucinations, agiation, hypersalivation, difficulty swallowing, hydrophobia, death within days on onset of symptoms
Diagnostic
-*negri bodies in eosinophilic cytoplasmic inclusions