CNS Infections Flashcards
(31 cards)
1
Q
Encephalopathy
A
Altered brain function/change in consciousness
2
Q
Encephalitis
A
Sudden onset brain inflammation
3
Q
Brain Abcess (causes)
A
- contiguous spread (sinus–>brain)
- hematogenous seeding (bacteremia–>brain)
- post-traumatic (injury, surgery leaving brain accessible)
- cryptogenic (idk why)
4
Q
Brain Abcess (locations)
A
frontal-temporal>frontal-parietal>cerebellar>occipital
-multiple regions = hematogenous spread
5
Q
Brain abcess (pathogens)
A
- streptococci, anaerobes, fungi
- NOT s. pneumo, H. influenza (they do meningitis)
6
Q
Brain abcess clinical signs
A
- headache
- slow progressive- weeks
- focal neurologic findings, seizures (since abcess presses on brain)
- nausea/vomiting
- fever+/- (unlike meningitis, +)
- no nuchal rigidity (unlike mengitis)
7
Q
Cranial Epidural Abcess
A
- Usually related to frontal sinus disease/osteomyelitis
- Elliptical shape (Epidural–>”E”lliptical)
8
Q
Cranial Subdural Abcess
A
- Emergency (like subdural hematoma, also crescent moon)
- Bacteremia related
- headache/seizure common
9
Q
Paraspinal abcess
A
- Epi/subdural
- bacteremia origin, can be contiguous spread
- S. aureus most common (most common metastatic infection in general)
10
Q
Spinal Subdural Abcess
A
- radicular pain (999/1000 sciatica, but with further symtoms diagnose SSA)
- urinary retention
- constipation
- leg weakness
- hyperreflexia
11
Q
Spinal Epidural Abcess
A
- Thoracic>Lumbar>Cervical
- Cord compression symptoms (radicular pain, urinary retention, constipation, hyperreflexia, leg weakness)
- Vertebral osteomyelitis common
- CSF shows Polys, elevated protein, normal/low glucose (indicating bacterial infection), can be culture -
- Posterior>anterior but presents the same
12
Q
Chronic Meningitis
A
Can be infectious/noninfectious
13
Q
Chronic Meningitis (infectious)
A
- TB
- cryptococcus (in immunocompromised)
- coccidioidomycosis
- histoplasmosis (mississippi r. valley)
- Lyme Disease
- Syphilis
14
Q
TB-caused chronic meningitis
A
- PPD -
- Need high index of suspicion (recent/past/current TB infection/TB endemic area)
- CSF: high protein, low glucose, lymphocytes (unlike bacterial meningitis- PMNs)
15
Q
Cryptococcus chronic meningitis
A
- immunocompromised patients
- stain with india ink
- Presents similar to fungal meningitis but with india ink stain
16
Q
Lyme Meningitis (chronic meningitis)
A
- Can occur at any stage of Lyme infection (unlike syphilis- just 2º/3º)
- CSF: Nonspecific lymphocyte (protein elevated, normal glucose, lymphocytes)
- Often see uni/bilateral Bell’s Palsy, headache, disrupted thoughts
17
Q
Syphilitic Meningitis (chronic meningitis)
A
- Common in 3º>2º syphilis, most frequent manifestation of 3º syphilis
- So suspect with Sexual history
18
Q
Meningovascular syphilis
A
- Endarteritis Obliterans causes small vessel stroke
- See stroke symptoms but no HTN or other indicators
- Seizures
19
Q
Parenchymatous Neurosyphilis
A
- Destruction of neurons in cortex shows PARESIS and Tabes Dorsalis
- psychiatric/neurologic issues
- PARESIS: Personality, Affect, Reflexes, Eye, Sensorium, Intellect, Speech
20
Q
Tabes Dorsalis
A
Less common
- shooting pains
- ataxia
- sphincter disturbance
- peripheral (decreased vibration) and cranial neuropathies
- uveitis, deafness, optic neuritis/atrophy
21
Q
Neurocysticercosis
A
- Caused by infection of Taenia Solium (pork parasite) with neural involvement
- Brain cysts cause epileptic seizures
- CSF: lymphocyte pleiocytosis (abnormal lymphocyte increase, 1000+), low glucose
22
Q
Non-Infectious Chronic Meningitis (causes)
A
- Neoplasms
- Sarcoidosis (looks like TB meningitis but more CN neuropathy)
- Vasculitis
- Drug-induced (bactrim, NSAIDs)
23
Q
Meningitis vs. Encephalitis
A
-Differentiate by altered mental status (E), neck stiffness (M). See fever, CSF alterations, headache in both.
24
Q
Viral Encephalitis CSF
A
Cell count <500
- Lymphocytes, though EES and other encephalopathies can have PMNs
- RBCs>500 in HSV, California Encephalitis, Colorado Tick Fever
- Glucose normal (since viral)- if low, consider alternative
- Diagnose with PCR, serology, MRI, brain biopsy (last resort)
25
Herpes Simplex Encephalitis
- Clinical suspicion (signs/Hx of HSV)
- lumbar puncture/PCR for HSV1
- MRI (show medial temporal lobe involvement), brain biopsy
- Treat with acyclovir
26
Viral Encephalitis Etiologies
```
HSV
CEF, CTEF
St Louis Encephalitis (SLE)
EEE
WEE
West Nile E
Varicella Zoster
```
```
Rare:
EBV
HIV
HHV-6
CMV
PML (progressive multifocal leukodystrophy- JC virus)
```
27
Eastern Equine Encephalitis (EEE)
Highest mortality encephalitis
- avian reservoir
- daytime mosquito feeder (unlike most night)
28
West Nile Encephalitis
-Greatest in elderly
-Fever + altered mental status
CSF: elevated protein, lymphocytes, normal glucose
-Can have muscle weakness/flaccid paralysis
29
Non-viral Encephalitis causes
Bacteria: Listeria, salmonella, nocardia (will culture + on lumbar puncture, glucose low)
- spirochetes
- rickettsia
- parasites
- mycoplasma
- drugs
- vasculitis
- carcinomatosis (cancer metastasis)
30
Naegleria Fowleri
- Freshwater amoeba
- causes acute hemmorrhagic encephalitis
- CSF: looks like bacterial (low glucose, PMNs, high protein), but becomes bloody in days (from hemorrhage)
- 99% mortality
31
Post Infectious Encephalitis
- kids>adults
- Acute Disseminated Encephalomyelitis (demyelination but no direct infection)
- multifocal neurologic symptoms
- CSF shows inflammation
- follows viral illness (MMR, mycoplasma, varicella, EBV, influenza..)
- treat with glucocorticoids. But need to diagnose prior encephalitis to properly treat
