CNS Infections Flashcards
What meningitis, what are 4 key pathogens involved for the bacterial kind?
E. coli, N. meningitidis, group B strep, Listeria
What is used for a rapid diagnosis of tuberculosis meningitis? How is this better than historical methods?
PCR of the CSF can diagnose rapidly; previously it would take a 4-6 week culture to diagnose.
What are the symptoms of a CNS infection with Borrelia burgdorferi?
- Starts with maculopapular rash
- Meningitis develops associated with cranial nerve palsies secondary to inflammation of nerve roots
- Organism enters brain to cause true encephalitis
What does a brain abscess present with?
Clinical findings of a rapidly expanding focal mass
What pathogens frequently spread to the brain to cause abscess from the: (also name where they lodge in the brain)
Sinuses (2)?
Mastoids (2)?
Hematogenous dissemination (2)?
Sinuses: Strep pneumo, H. influenzae, lodge at frontal lobe
Mastoids: Strep pneumo, Pseudomonas, lodge at temporal lobe
Hematogenous: Staph aureus and Strep milleri), lodge at gray/white matter junction
What appears radiologically with a brain abscess?
Ring enhancing mass; differs clinically from a ring-enhancing neoplasm due to acuteness of symptomatology
What is the most common form of fungal CNS infection, and what is it called when there is infection of brain vessels and brain tissue?
Aspergillosis. Notable for necrotizing angiitis where there is significant infection of blood vessels as well
What is the most common parasitic infection of the CNS in the world?
Cysticercosis. Second to this is probably cerebral malaria
What is cerebral toxoplasmosis associated with?
AIDS patients, associated with multifocal ring enhancing lesions of the brain with necrotizing abscesses with coagulative necrosis
What are the 3 groups of viral CNS infections?
Acute, chronic, and herpes viral infections
What is the most common cause of viral meningitis?
Enteroviruses
What brain matter is associated with polioencephalitis? What about leukoencephalitis? Primary example of each?
Polioencephalitis = gray matter
Leukoencephalitis = white matter
Poliencephalitis commonly seen with enteroviral infections, rabies, arboviruses. Leukoencephalitis seen with PML (JC virus) and post infectious demyelinating diseases
What is rabies viral infections of the CNS notable for’?
Mild perivascular inflammatory response without tissue necrosis
What are virtually all cases of paralytic polio associated with?
Poliovirus which is a family of enteroviruses, causes pan-hemorrhagic involvement of the ventral portions of the spinal cord gray matter
What is post-infectious encephalomyelitis?
Not a viral encephalitis per se, but is an autoimmune response that develops in the week or two after acute viral infection or vaccination; molecular mimicry leading to perivenular demyelinating disease
