CNS INFECTIONS Flashcards
inflammatory process of leptomeninges and CSF within the subarachnoid space
Meningitis
combines this with inflammation of the brain parenchyma
Meningoencephalitis
what are the types of CNS infections?
acute pyogenic meningitis
chronic meningoencephalitis
brain abscess
parenchymal infections
name this Chronic Meningoencephalitis:
may be a part of systemic disease or isolated (seeding of brain from a silent, usually pulmonary, lesion)
Tuberculous Meningitis
name this Chronic Meningoencephalitis:
the tertiary stage of syphilis
Neurosyphilis
chronic meningitis w/ obliterative endarteritis & perivascular plasma cell infiltrate, what is this subtype of neurosyphilis
Meningeal Neurosyphilis
invasion of brain by treponemal organisms w/ brain atrophy& resultant severe dementia, what is this subtype of neurosyphilis
Paretic Neurosyphilis
damage to the dorsal root sensory nerves w/ impaired sensation & absence of deep tendon reflexes (similar to neuropathy), what is this subtype of neurosyphilis?
Tabes Dorsalis
lesions w/central liquefactive necrosis, surrounded by fibrous collagen capsule & edema
Brain Abscess
Caused by the poliovirus (which has since been controlled by immunization)
enterovirus attacks lower motor neurons
flaccid paralysis, muscle wasting, hyporeflexia
progressive weakness w/ decreased muscle bulk & pain
what is this parenchymal infection?
Poliomyelitis
Viral encephalitis caused by JC virus
Focal, progressive neurologic symptoms
Occurs in immunosuppressed individuals
Most people have serologic evidence of exposure by the age of 14
Morphology: ill-defined white matter injury
what is this parenchymal infection?
Progressive Multifocal Leukoencephalopathy
A rare, progressive clinical syndrome
Characterized by:
• Cognitive decline
• Limb spasticity
• Seizures
Typically occurs in children or young adults
The disease stems from a persistent, but nonproductive infection of the CNS by an
altered measles virus
Morphology:
Widespread gliosis and myelin degeneration
Viral inclusions
Variable inflammatory infiltrate of white and gray matter
Neurofibrillary tangles
Disease persists in non-vaccinated populations
what is this parenchymal infection?
Subacute Sclerosing Panencephalitis
routes of entry?
○ Hematogenous spread
○ Direct implantation (traumatic, iatrogenic i.e. surgery)
○ Local extension (sinuses, cranial bones)
○ Peripheral nervous system (ex. Rabies, Herpes)
name this causative organism for acute pyogenic meningitis for:
neonates
E. coli (maternal feces) & Group B Strep. (vaginal flora)
name this causative organism for acute pyogenic meningitis for:
infants
H. influenza & Strep. pneumoniae
name this causative organism for acute pyogenic meningitis for:
teens
Neisseria meningitidis (vaccine doesn’t cover all of the serotypes)
name this causative organism for acute pyogenic meningitis for:
elderly
Strep. pneumoniae & Listeria monocytogenes (deli meats, cheeses)
what disease
Clinical Findings
▪ Symptoms: headache, photophobia, irritability, clouding of consciousness, neck stiffness
▪ CSF: cloudy, purulent, increased pressure, increased neutrophils, *increased protein, and *decreased glucose (bc the bacteria ate it all)
Acute Pyogenic (Pus) Meningitis
(can cause hydrocephalus) - large quantities of capsular
polysaccharide of causative organism produces particularly gelatinous exudate that encourages arachnoid fibrosis
this is a morphology for acute pyogenic meningitis?
Chronic adhesive arachnoiditis
thick layer of suppurative exudate covers brainstem and
cerebellum and thickens the leptomeninges
Pyogenic meningitis
name this disease:
Chronic bacterial infections; may be caused by M. tuberculosis, T. pallidum, and Borrelia
Chronic Meningoencephalitis
what disease
Clinical Findings:
• Symptoms – headache, malaise, mental
confusion, vomiting
• CSF – mononuclear cells, increased protein, normal/decreased glucose
Tuberculous Meningitis of Chronic Meningoencephalitis
well circumscribed intraparenchymal mass
Tuberculoma
what are the subtypes of chronic meningoencephalitis?
tuberculous meningitis
neurosyphilis
what are the subtypes of neurosyphilis?
Meningeal Neurosyphilis
Paretic Neurosyphilis
Tabes Dorsalis
what are the predisposing conditions of brain abscess?q
Predisposing conditions • acute bacterial endocarditis • cyanotic congental heart disease • right-to-left shunt • chronic pulmonary sepsis
clinical signs of poliomyelitis?
this is a syndrome of poliomyelitis that is progressive weakness w/ decreased muscle bulk and pain
flaccid paralysis, muscle wasting, hyporeflexia
Post-polio Syndrome
name this disease:
Viral encephalitis caused by JC virus
kills oligodendrocytes and causes demyelination
Progressive Multifocal Leukoencephalopathy
this disease is characterized by cognitive decline, limb spasticity, seizures
altered measles virus
subacute sclerosing panencephalitis
