What are common symptoms of meningitis?
- HA
- Neck Stiffness
- Fever
- Photophobia
What are the most common causes of viral meningitis?
- Coxsackie Virus
- Echovirus
- Arbovirus (Mosquito)
If a healthy 34 year old male presents to the ED with a headache with a fever and CT reveals a well-circumscribed lesion, what might be the infectious agent responsible?
- Staph Aureas
- - Strep
What are characteristic findings of brain abscesses to have a confirmatory diagnosis?
- Well-circumscribed lesion with central necrosis
- Fibrotic Wall of collagen
- Numerous PMNs surrounding
- “Ring Enhancement Lesion” on imaging
What might be the CSF findings of TB-associated meningoencephalitis?
- Elevated Lymphocytes
- - Low Blood Glucose
What are unique characteristics of TB-meningoencephalitis?
- Enhancement of the base of brain on MRI + vasculitis
- Tuberculoma - mass lesion w/ central caseous necrosis with Epithelial Histiocytes / Giant Cells
- Pott’s Disease - granulomatous process of vertebral bodies leading to cord compression
What chronic infection is manifests with general paresis, meningovascular meningitis, and tabes dorsalis?
Treponema Pallidum
- gradual cognitive impairment
- chronic multifocal arteritis–infarctions-thickening of vessels walls until occulsion
- -Lightning pains, loss of positional-vibrational senses
If on an after death autopsy you unconver perivascular lymphocytic infiltrates, microglial nodules, and neuronophagia; what might have been a pathologic process occurring at the time of death?
Viral Encephalitis
–Those symptoms are consistant with general viral encephalitis
A 27 year old female presents to the emergency department with abnormal behavior according to friends and erratic moods complaining of a headache several days ago. What might be found on MRI scan?
HSV1 Most Likely
- Focal abnormalities of the Temporal Lobes
- Hemorrhagic inflammatory necrosis / swelling
If a biopsy what taken of an individual thought to have Herpes Simplex encephalitis what might they find?
- Intranuclear inclusion bodies
- Cowdry Type A Cells
Contrast the patient populations who acquire HSV1 and HSV2 encephalitis?
HSV1 – General Population
HSV2 – Neonates who acquire HSV2 from active infection in the mother during birth.
How is Arbovirus acquired and when should you be suspicious of Arbovirus?
Mosquitos – Season, most common during the summer.
Epidemic Encephalitis – when several people in the community contract it.
What virus most common affects Microglial cells?
HIV
What are the symptoms associated with chronic HIV infection?
Infect Microglial Cells
- develop HIV Encephalitis over time (years)
- Cognitive/Behavioral deterioration
- Ataxia / Tremor
What histologic findings is consistent with HIV encephalitis?
Microglia Nodule with Multinucleated microglial cells
What conditional affects the oligodendrocytes?
Progressive Multifocal Leukoencepholopahty
What is responsible for Progressive Multifocal Leukoencephalopathy?
Reactivation of JC Virus
– Immunocompromised individuals
How does Progressive Multifocal Leukoencephalopathy affect the brain?
- Affects white matter
- numerous irregular small focal areas of demyelination of the white matter
- oligodendrocyte inclusions
What might you find with Apergillus / Mucor encephalitis?
– Vasculitis causing small localized hemorrhage infarcts
if Aspergillus – vessels infiltrated with hyphae
Where does Cryptococcosus come from and how does it end up infecting the brain?
Immunocompromised individuals
- Bird Poop
- Infects the lungs first, then hemagenously spreads to the brain cauing encephalitis/abscesses
What are histologic findings with Cryptococcus?
- Thickening of the Meninges from chronic inflammation
- Intraparenchymal cysts – “Soap Bubbles”
- Yeast form of fungi
If you become infected with Toxoplasma what might the pathologic findings be?
- Very small areas of necrosis throughout the brain
- Organisms free in tissue in pseudocysts
What are the common causes of Epidural / Subdural empyemas?
Hematagenous spread from ENT infection
- Strep
- Staph
What is the common clinical presentation of Prion Disease?
Rapid progression of dementia, ataxia, myoclonic jerking
– EEG = triphasic waves 1-2s
– MRI = increased signal in basal ganglia
Symptom onset progression in months, death within a year.
