CNS Infections & Pathology Flashcards
Asplenic or complement-deficient individuals are at higher risk for infection caused by what bacteria?
N. meningitidis
What organisms are most likely to cause viral meningitis in infants, children, and adults?
Enteroviruses, Arboviruses
What is the most common arbovirus in the US?
West Nile Virus
Tabes dorsalis is a potential complication of what type of meningitis?
Neurosyphilis meningitis
What are common causes of granulomatous amebic encephalitis?
Acanthamoeba & Balamuthia mandrillaris
What is the cause of neurocysticercosis?
Ingestion of Taenia solium eggs
What is Waterhouse-Friderichsen Syndrome?
Meningitis-associated septicemia that causes hemorrhagic infarction of the adrenal glands
A 70yo woman comes to the clinic. She has developed progressive muscle weakness over the past several months. All tests are normal. The patient reports polio infection as a child and believes her symptoms are related. Is this possible?
Yes - Post-Polio Syndrome potentially due to neuronal wear and tear
This type of poliovirus disease has no CNS dissemination.
Abortive poliomyelitis
What bacterial organisms are most likely to cause acute meningitis in immunocompromised persons?
Cryptococcus neoformans, Listeria monocytogens, Toxoplasma gondii
How is the rabies virus transmitted?
Via saliva - a bite closer to the head is more likely to develop into rabies
HSV is the most common cause of acute viral meningitis in what population?
Newborns
What unusual CSF finding may be seen in an immunocompromised patient with meningitis due to Listeria?
Presence of lymphocytes. Generally, only neutrophils are present with bacterial meningitis.
A well-circumcised intraparenchymal mass due to chronic tuberculosis infection is called…?
Tuberculoma
Why is N. meningitidis known to cause skin lesions, such as papules and petechiae?
Outer membrane has lipo-oligosaccharide that triggers immune response and vascular damage
H. influenzae is most common among what populations?
Unvaccinated children, people with other medical conditions
A patient comes to the ER complaining of rapid onset, asymmetric limb weakness. CN abnormalities are present, but seizures, LOC, altered mental status, and nuchal rigidity are not. What is a potential diagnosis?
Acture Flaccid Myelitis
What enteroviruses are most associated with meningitis?
Echovirus, Coxsackievirus
What is the classic presentation of neuroborreliosis (Lyme disease meningitis)?
Aseptic meningitis, facial nerve palsy, radiculoneuritis
What is the empiric treatment for bacterial meningitis?
Ceftriaxone
True/False. Photophobia and nuchal rigidity are present in both meningitis and encephalitis, making it difficult to differentiate between the two diseases.
False. Nuchal rigidity and photophobia are NOT present in encephalitis, but may be present in meningitis and meningoencephalitis.
This is the paralyzing type of polio disease.
Paralytic poliomyelitis
What is the leading cause of viral encephalitis?
HSV-1
Where does poliovirus first target upon entering the CNS?
Motor neurons in the anterior horn of the spinal cord
What CNS cell serves as a reservoir for HIV?
Microglial cells
Arthropod viruses generally target what CNS structures?
Cortex, cerebellum, spinal cord
What will CSF analysis during viral meningitis show?
Normal/increased opening pressure, Lymphocytes, normal/decreased glucose, moderately elevated protein
The bacteria is a gram-positive diplocci and number one cause of meningitis in adults.
S. pneumoniae
Subdural empyemas (pockets of pus) are most often due to what etiology?
Bacterial infection - rarely occur in arachnoid or subarachnoid spaces
What is the morphology of the second-leading cause of meningitis in adults?
N. meningitidis - Gram negative diplocci
What is a classic finding on imaging due to toxoplasma gondii infection?
Ring-enhancing lesions
What is the inactivated form of the polio vaccine used in the US?
Salk vaccine
Brain abscesses may present with focal neurologic deficits and/or increased intracranial pressure. What are potential complications of these abscesses?
Fatal brain herniation, abscess rupture, venous sinus thrombosis
What are the most common causes of neonatal meningitis?
S. agalactiae (GBS), E. coli, Listeria monocytogenes, HSV
What is the recommended treatment for potential rabies infection?
Wound treatment, local administration of rabies immune globin, vaccination
What is the effect of the JC virus on the white matter of the brain?
Demyelination
What virus is more likely to cause severe neuroinvasive disease in children under 16yo?
La Crosse Virus