Encephalitis/Meningitis Flashcards
What are the 3 causes of CNS infections?
- Invasion of bloodstream
- Retrograde neuronal pathway-Olfactory or peripheral nerves
- Direct contiguous spread
Encephalitis presentation
- AMS
- Motor and or sensory deficits (abnormal cerebral function)-Focal neuro sx’s, CN deficits
- Seizures
- Altered behavior and/or personality change
- Profound lethargy
- Fever
What is the number one cause of encephalitis?
Viral: HSV-1 (MC)
Who is @ high risk for encephalitis?
- Outdoors
- Tavel to endemic areas
- Immunocompromised
- Lack of vaccines
List the viral causes of encephalitis
- Herpesvirus
- West Nile Virus- Arthorpod-borne viruses
- Rhabdovirus
- HIV
- Coxsackie-enteroviruses
- Measles
List bacterial causes for encephalitis
- Borrelia Burgdorferi (lyme dz)
- M. tuberculosis (TB)
- T.pallidum (Syphillis)
What organism would you suspect with flaccid paralysis PE findings?
West Nile Virus
List autonomic and hypothalamic disturbances you may find on physical exam findings in encephalitis
- Loss of temp and vasomotor control
- Diabetes insipidus
- Syndrome of inappropriate secretion of antidiuretic hormone (SIADH)
What is the preferred imaging for encephalitis? What area of the brain is MC involved?
MRI
Temporal lobe-HSV
Encephalitis CSF findings
- Lymphocytosis
- Normal glucose
- Increased protein
- Straw colored
When is an LP contraindicated?
- Sign/Sx’s of Increased ICP: Decreased LOC, Focal neurologic sx’s, Papilledema
- Severe coagulopathy or on anticoagulant therapy
- Skin infection or spinal abscess @ LP site
- Mass lesion
Cushings triad
Sigs of increased ICP:
- Respiratory depression
- Bradycardia
- Hypertension
Caused for Pink-Red CSF
- Traumatic LP
- Subarachnoid hemorrhage
- Intracerebral hemorrhage
- Cerebral infarct
What does leukopenia and thrombocytopenia on a CBC indicate?
Ricketssial
Viral fevers
What does eosinophilia on a CBC indicate?
Drug induced encephalitis
Parasites
What does hyponatremia indicate?
Rickettsial infection
SIADH
What is the gold standard for encephalitis diagnosis?
Brain biopsy
Not routinely performed
What is the most important treatment intervention in encephalitis? Why?
Acyclovir early
Decreases morbidity and mortality due to HSV and VZV encephalitis
Meningitis risk factors
- Extremes of age
- Exposure risk-Close proximity
- Birth hx/maternal infection
- Vaccine status
- Injection drug use
What is the number one cause of viral meningitis?
Enteroviruses: Coxsackie, herpangina
What strain of HSV do we see in viral meningitis?
HSV-2
CSF findings in viral meningitis?
- Clear or cloudy
- Lymphocytosis
- Normal glucose
- Increase protein
Pathogen in neonates in bacterial meningitis
Group B Streptococcus
Pathogen in babies and children in bacterial meningitis
S. peneumoniae
Pathogen in teens and young adults bacterial meningitis
N. meningitidis
Accompanying petechial/purpra rash
Pathogen in adults in bacterial meningitis
S. peneumoniae
bacterial meningitis presentation
- Fever/chills
- Meningeal sx: HA, nuchal rigidity, kernigs sign, brudzinski
- AMS (DO NOT have to have this)
- N/V
- Photophobia
When would you want to get a CT scan before LP?
signs of increased ICP–>r/o mass effect
What is the first treatment intervention you want to do in bacterial meningitis?
Start empiric abx!!!
What is the definitive dx for bacterial meningitis?
LP
CSF findings in bacterial meningitis
- Neutrophils
- Decrease glucose (<45)
- Increased protein
- Increased CSF pressure
- Yellow color
What is empiric abx treatment in bacterial meningitis?
Ceftriaxone or Cefotaxine (3rd generation)
+ Vanco
+Ampicillin IF 50+
What is empiric abx treatment if you have a severe beta-lactam allergy in bacterial meningitis?
Vancomycin
+ Fluroquinolone (Moxifloxacin)
What is empiric abx treatment if you have a severe beta-lactam allergy in bacterial meningitis AND you are 50+?
TMP-SMX
Who is Dexamethasone recommended for?
Suspected S. pneumoniae
Decreases risk of developing neurologic sequela that is highly associated with S.pneumo
Who is post-exposure prophylaxis indicated for?
- Prolonge contact: >8 hrs while in close proximity, <3 ft
2. Direct exposure to patients oral secretions during 7 days prior to sx’s onset AND until 24 hrs after initiating abx
What serogroups does the quadrivalent meningococcal conjugate vaccine protect against?
A, C, W & Y
Who is Menactra approved for?
9 mos-55 yrs.
Who is Menveo approved for?
2 mos-55 yrs.
List the vaccines that cover against serogroup B
- Trumenb: 10-25 yrs, 2-dose and 3 dose series
2. Bexsero: 10-25 yrs, 2-dose
Who is Trumenb and Bexsero indicated for?
- Persistent complement component deficiency
- Asplenia
- Microbiolgist routinely working with N.meningitidis
- @ high risk
