Neurologic Infections Flashcards
Meningitis
Invasion of meninges by microorganism
Infection involves: Pia, arachnoid, subarachnoid/CSF (most)
Secondary involvement - blood vessels/brain parenchyma due to spasms
Viral Meningitis
Aseptic - unknown
Viral - enterovirus most common, self-limiting
Complication of systemic - mumps
Bacterial Meningitis
Brain not primary infection site - secondary infection
Sporadic/Epidemic - meningococcus***
SSX
Chills, fever HA Neck pain/stiffness Altered mental state Seizure Petechial rash - meningococcus
Neonatal BM
GBS
E. coli
Children BM
H. influenzae - lower incidence with vaccine
Adult BM
Streptococcus pneumoniae
Neisseria meningitidis
Listeria monocytogenes (neonates also)
Why would no organism show on culture?
Antibiotics in CSF reduce growth on culture
Sequelae
Focal neurologic deficits Cranial nerve palsies Seizures Hydrocephalous Myelopathy/radiculopathy Death
DX of Meningitis
Confirmed by CSF analysis
Obtain LP BEFORE antibiotics
Other: high WBC, CT/MRI, sinus X-ray, blood culture
Cells, Protein, Glucose - Bacterial Purulent
High Polys (>1,000)
High protein
Low glucose (<20)
Gram stain, C/S, Ab titers
Cells, Protein, Glucose - Viral
High Monos
Normal to high protein
Normal to low glucose
Cultures, stains, Ab titers, PCR
Cells, protein glucose - fungal
High mixed cells (10-500)
Very high protein
Low Glucose (15-35)
Culture, india ink, Ag titer
Cells, protein glucose - TB
High mixed cells (<500) Extremely high protein Low glucose (20-40) Acid-fast, culture Cloudy, ground glass clots
BM TX
Antibiotics - Cephs, Vanco
Supportive - hydration, ventilation, anticoag
TB Meningitis
Subacute/secondary
Rupture of tubercle into CSF
Present: HA, cognitive dysfunction, WL
DX - brain scan, CSF, biopsy
CNS Abscess
Brain, spinal cord, epidural
Secondary to blood metastasis, direct extension, perforating wounds
Possible: Anaerobic/aseptic
Myelitis
Spinal cord infection
Leprosy
Chronic infection of skin/peripheral nerves
Granulomatous nerve deterioration
SX: anesthesia, motor loss, limb/joint deformities - cutaneous/peripheral
TX - dapsone, rifampin, clofazimine
Encephalitis
Infection of parenchyma secondary to viral infection
W/spinal involvement - encephalo-myelitis
W/meningeal involvement - meningo-encephalitis (aseptic meningitis)
DX - virus isolation in CSF - most common HSV
Poliomyelitis
Enterovirus 1st acute infection - later flaccid paralysis (a-MN) Occasional brain involvement Respiratory/bulbar dysfunction Post-polio syndrome 30-40 years later
Herpes Simplex Encephalitis
Most significant sporadic encephalitis Endogenous reactivation of latent virus Abrupt onset with fever, HA, malaise Abnormal EEG/MRI TX: Acyclovir, steroids, anticonvulsants
Zika Virus
Mostly asymptomatic
Fever, flu-like
Prenatal microcephaly
Post-infectious Guillain-Barre - AIDP (acute inflammatory demyelinating polyneuropathy) - weakness in legs, slow progression to hands/head/respiratory
AIDS
Secondary to HIV 1 infection
Neurotropic - prefers brain
HAART - highly active anti-retroviral therapy
