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Neuro: Clin Med IIB > CNS Infections > Flashcards

CNS Infections Flashcards

1
Q

inflammatory disease of the meninges surrounding the brain and spinal cord

what disorder?

A

meningitis
Bacterial, Viral or Fungal

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2
Q

inflammation of both the brain and the meninges

what disorder?

A

Meningo-encephalitis

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3
Q

acute inflammation of the brain itself/brain parenchyma

what disorder?

A

encephalitis
Bacterial, Viral, (Parasitic, Fungi, Spirochetes)

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4
Q

a collection of purulent material within the brain tissue resulting from inflammation of a nearby or remote source

what disorder

A

Brain Abscess

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5
Q

general s/s of CNS infections

A
  1. Fever
  2. HA
  3. Altered mental status
    - confusion, memory loss, loss of alertness, disorientation, defects in judgment or thought, unusual or strange behavior, poor regulation of emotions, and disruptions in perception, psychomotor skills, and behavior
  4. Meningeal signs
    - nuchal rigidity, (+) Kernig/Brudzinski
  5. Increased intracranial pressure (ICP)
    - Papilledema, poorly reactive pupils
    - Abducens (6th CN) palsy - horizontal diplopia
    - N/V
    - Bulging fontanelle (soft spot) in infants
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6
Q

which meninges layer is the outermost layer - strong fibrous membrane

A

dura mater

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7
Q

which meninges layer is middle layer with cobweb like filaments that attach to the innermost layer

A

Arachnoid Mater

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8
Q

which meninges layer is the space between arachnoid and pia mater - filled with CSF and contains blood vessels

A

Subarachnoid Space

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9
Q

which meninges layer is the innermost layer - a very thin and delicate membrane that is tightly to bound the surface of the brain

A

Pia Mater

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10
Q

an acute purulent infection of the arachnoid mater and the subarachnoid space

A

Bacterial Meningitis

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11
Q

pathophys of Bacterial Meningitis

A

MC from previously colonized distant infection

  1. Nasopharynx, rsp tract, skin, GI tract and GU tract
  2. Access to CNS by 2 processes:
    - hematogenous spread - MC
    - direct contiguous spread
    — sinusitis, otitis media, mastoiditis, trauma, neurosurgical procedures

Newborns

  1. pathogens colonized from the maternal intestinal or genital tract
  2. transmitted from nursery personnel or caregivers at home
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12
Q

pathogenetic causes of bacterial meningitis in adults?

A

Community acquired

  1. Strep pneumo (MC)
    - MC cause in adults >20 yrs old
  2. Group B Strep (GBS) (~15-20%)
  3. N meningitidis (~10-20%)
  4. H flu type B
  5. Listeria monocytogenes (< 5%)

Healthcare acquired

  1. S. aureus and coagulase-negative staphylococci (normal skin flora)
    - MC after neurosurgical procedures
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13
Q

pathogenetic causes of bacterial meningitis pediatrics

A
  1. Neonatal
    - GBS
    - E coli
    - G-bacilli
  2. Children > 1 month
    - Strep pneumo
    - N meningitidis
    - H flu type B (Hib)
    — MC in unvaccinated
    - GBS
    - G- bacilli
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14
Q

presentation of adult bacterial meningitis

A
  1. HA - MC
  2. F - 2nd MC
  3. Nuchal rigidity/meningeal signs
  4. Decreased LOC/altered mental status
  5. N/V
  6. photophobia
  7. seizure
  8. increased ICP
    - papilledema, CN palsy III, IV, VI, VII
    - N/V, change in LOC, confusion
  9. meningococcal rash
    - maculopapular rash that become petechial and/or purpuric involving the trunk, LE, mucosal membranes, conjunctiva
    - seen in septic meningitis with N. Meningitidis

triad - HA, F, meningeal signs - present <50% of cases

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15
Q

where to look for primary source of infection in adult bacterial meningitis

A

sinus
ears
mastoid
evidence of semi-recent trauma/surgery

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16
Q

presentation of Bacterial Meningitis - Pediatrics

A
  • Fever or hypothermia
  • Lethargy
  • Restlessness/irritability
  • Poor feeding/ decreased appetite
  • Vomiting/diarrhea
  • Respiratory distress
  • Seizures
  • Jaundice
  • Bulging fontanel (infants)

S/S in older children

  • Confusion
  • HA
  • Photophobia
  • Meningeal signs - Kernig, Brudzinski
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17
Q

Hx red flags for bacterial meningitis

A
  1. Recent exposure to similar illness
  2. Recent illness or antibiotic treatment
    - Ex: pneumonia, sinusitis, otitis, mastoiditis, endocarditis
  3. Recent travel to areas with endemic disease
    - Meningococcal disease (sub-Saharan Africa/India)
  4. Penetrating head trauma
  5. CSF otorrhea or CSF rhinorrhea
    -Hx of skull fracture
  6. Cochlear implant devices
  7. Recent neurosurgical procedures
    - most often a ventriculoperitoneal (VP) shunt
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18
Q

Most important Work-Up and Management for bacterial meningitis

A
  1. Immediate collection of blood cx x 2
    - gram stain, cx & sensitivity (C&S)
  2. Prompt LP w/ CSF evaluation

DO NOT delay empiric Abx therapy for LP or CT
Would still get CBC, chemistry panel, etc

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19
Q

Infectious Diseases Society of America (IDSA) guidelines recommend CT scan before LP if: (6)

A
  1. Immunocompromised
  2. Hx of CNS dz - mass lesion, stroke, or focal infection
  3. New seizure (w/n 1 wk of presentation)
  4. Papilledema
  5. Abnml LOC
  6. Focal deficits
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20
Q

what are the 4 tubes in a CSF analysis?

A

Tube 1 - Cell count and diff
Tube 2 - Glucose and protein levels
Tube 3 - Gram stain, C&S
Tube 4 - Cell count and diff (if repeat is needed) or special additional studies (depending on initial CSF analysis)

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21
Q
  1. Pressure - 80-200 mmH2O
  2. Appearance - Clear, water-like
  3. WBC Count - 0-5 (lymphocytes) cells/µL
  4. Glucose - 50-75 mg/dL
  5. Protein - 14-40 mg/dL
  6. Additional Studies
    - CSF : serum glucose ratio > 0.6
  7. Microbiology - Negative findings on workup

how would you analyze this CSF?

A

normal

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22
Q
  1. Pressure - 200-300 mmH2O
  2. Appearance - Cloudy, purulent
  3. WBC Count - 100-5000 (l>80% PMNs) cells/µL
  4. Glucose - <40 mg/dL
  5. Protein - >100 mg/dL
  6. Additional Studies
    - Lactate ≥ 31.53 mg/dL
    - CSF : serum glucose ratio <0.4
  7. Microbiology - (+) 60% of Gram stains and 80% of cx

how would you analyze this CSF?

A

bacterial meningitis

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23
Q
  1. Pressure - 90-200 mmH2O
  2. Appearance - clear
  3. WBC Count - 100-300 (lymphocytes) cells/µL
  4. Glucose - normal or slightly low
  5. Protein - normal or slightly high
  6. Microbiology - isolation, PCR assys

how would you analyze this CSF?

A

viral meningitis

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24
Q

Additional labs for Bacterial Meningitis

A
  1. CBC - PMN leukocytosis (left shift)
  2. CMP
    - glucose - compare with CSF glucose
    - liver and kidney function for abx dosing adjustments
  3. Coag profile (INR, APTT, platelets and fibrinogen)
    - helps to differentiate who may need platelet or FFP after LP
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25
Q

additional imaging for bacterial meningitis

A
  1. Non urgent CT/MRI to rule out differential diagnoses
    - MRI is preferred due to is superiority in demonstrating cerebral edema but not readily available
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26
Q

begin abx therapy for bacterial meningitis within ? of patient arrival

A

60 minutes

Administered immediately after LP
DO NOT delay abx therapy if LP is delayed

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27
Q

therapy for bacterial meningitis

A

empiric

  1. ALL PTs
    - dexamethasone
    - Given 0-20 min. prior to 1st dose abx and continued x 4 d
  2. Healthy 1m - 50 yr
    - ceftriaxone (any 3rd/4th-gen) PLUS
    — Alt: cefotaxime or cefepime
    - vancomycin PLUS
    - acyclovir + ampicillin/doxy/metronidzaole
    — HSV encephalitis is a top DDx
  3. Infants < 1 mo
    - cefotaxime + ampicillin
  4. general management
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28
Q

Substitute ceftriaxone with what other meds in neurosurgical or neutropenic pts to cover P. aeruginosa in bacterial meningitis?

A

ceftazidime or meropenem

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29
Q

ceftriaxone is CI in neonates due to?

A

risk of hyperbilirubinemia

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30
Q

you would choose ampicillin as the individualized care for bacterial meningitis for ?

A
  1. <1 month and >50 years old
  2. immunocompromised
    - chronic illness, organ transplant, pregnancy, malignancy, immunosuppressive therapy
  3. covers L. monocytogenes
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31
Q

you would choose doxy as the individualized care for bacterial meningitis for ?

A

tick season to cover tick-borne bacterial infections

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32
Q

you would choose metronidazole as the individualized care for bacterial meningitis for ?

A

covers gram-negative anaerobes coinciding otitis, sinusitis or mastoiditis

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33
Q

general management for bacterial meningitis

A
  1. Supportive care
    - monitor VS and treat as appropriate
    - IV fluids
    - control fever, pain
  2. Control of ICP
    - elevation head 30–45°
    - intubation with hyperventilation
    - mannitol
  3. Adjust abx after G stain (24-48 h) and C&S have returned (48-72 h)
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34
Q

Antibiotic therapy duration for bacterial meningitis (each causative agent)

A

N. Meningitidis - 7 days
H. Influenzae Type B - 7 days
S. Pneumoniae - 10-14 days
S. Aureus - at least 14 days
L.monocytogenes - 21 days

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35
Q

indications for repeat CSF analysis

A
  1. No improvement w/n 48 h after the initiation of appropriate therapy
  2. Microorganisms resistant to standard abx
    - 2-3 days after the initiation of therapy
  3. Persistent fever > 8 d (without other known cause)

Repeat CSF cultures should be sterile

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36
Q

If cultures remain positive despite appropriate therapy after repeat CSF cx, consider to do what?

Bacterial Meningitis

A

intrathecal (or intraventricular) abx administration

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37
Q

Mortality in bacterial meningitis is highest when?
decreases in ___, and increases again in _____

A

increase - in the first year of life
midlife, old age

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38
Q

Common neurologic sequelae after bacterial meningitis - temporary or permanent

A

decreased intellectual function
memory impairment
seizures
hearing loss and dizziness
gait disturbances

39
Q

prevention/precautions with bacterial meningitis?

A
  1. Droplet precaution
    - all pts until etiology is determined
    - continue for 24 h after start of abx in N. meningitidis
  2. Chemoprophylaxis
    - close exposure to meningitis w/ H flu - rifampin x 4 d
    - close exposure to N. meningitidis - rifampin x 2 d
    - GBS - prophylactic IV PCN during delivery
    - Neurosurgery
40
Q

indications for chemoprophylaxis (H. flu) for bacterial meningitis?

A
  1. Contact for ≥4 h for at least 5 out of the 7 d before admission of index pt
    - Anyone exposed under the age of 2 years
    - Anyone exposed who lives in a home with a child < 4 y/o
    - Anyone exposed who is not fully immunized against Hib
41
Q

indications for chemoprophylaxis (H. flu) for bacterial meningitis?

A

prolonged (>8h) exposure in close proximity (<3 ft)
direct exposure to oral secretions
Exposure 7 days before onset of sx up through 24 hrs after initiation of abx

42
Q

alt tx for chemoprophylaxis for N. meningitidis - Bacterial Meningitis

A
  • ciprofloxacin 500 mg PO
  • ceftriaxone 250 mg IM once
43
Q
  • Vaginal/anal swab testing for group B strep when for chemoprophylaxis of bacterial meningitis?
  • TX if positive?
A

between 35-37 wks gestation
prophylactic IV PCN to be administered during vaginal delivery if (+)

44
Q

Perioperative antimicrobial prophylaxis for bacterial meningitis is indicated for who?

A

patients undergoing any form of neurosurgery

45
Q

The most effective way to prevent meningitis is ?

A

vaccination

Streptococcus pneumoniae (PVC13, PPSV23)
Neisseria meningitidis (MenB and MenACWY)
Haemophilus influenzae Type B (Hib)

46
Q

a condition that presents with evidence of meningeal inflammation (H&P & CSF profile) with a negative bacterial culture

A

Viral (Aseptic) Meningitis

47
Q

MC cause of Viral (Aseptic) Meningitis

A

enteroviruses - coxsackieviruses, echoviruses, human enteroviruses

48
Q

risk factors for viral meningitis

A
  1. Infants <1 Month old
    - Most cases children < 5 y/o
  2. Immunodeficient patients- at risk for more severe infection
  3. Exposure to someone with viral meningitis
49
Q

Historical Features for viral meningitis

A
  1. Comprehensive travel and exposure hx
    - concentrate on areas of endemic West Nile virus, Lyme disease, other tick borne disease
  2. Ill contacts with similar sx or viruses
  3. Vaccination hx
  4. Sexual exposure - HSV-1/2, HIV, syphilis
50
Q

presentation of viral meningitis

A

similar to bacterial meningitis - often less severe

  1. HA
  2. Photophobia and/or pain with EOM
  3. Nuchal rigidity
  4. Constitutional sx - malaise, myalgia, anorexia, N/V/D, abdominal pain
  5. Mildly diminished LOC - drowsiness or mild lethargy
    - if there is a marked decrease in LOC consider other diagnosis

profound alterations in LOC, seizures and focal neuro deficits are not seen

51
Q

what are the specific findings of viral meningitis

A
  1. Diffuse maculopapular exanthem - enteroviral infection, primary HIV or syphilis
  2. Parotitis/Orchitis - mumps
  3. Genital/Oral Lesions - HSV
  4. Thrush - HIV
  5. Asymmetric flaccid paralysis - West Nile
52
Q

work-up (labs) for viral meningitis

A

LP - same approach as bacterial meningitis

  1. opening pressure with CSF analysis (same as bacterial)
    - WBC - lymphocyte predominant
    - Gram’s stain of CSF will be negative for any growth
  2. CSF PCR amplification of viral nucleic acid
    - PCR - CSF PCR for each individual virus
    — highly sensitive and specific but never 100% correct - always use clinical judgement

CBC, CMP, coags - non-revealing in viral

Amylase - elevated in mumps

Blood, feces, and throat swabs for viral etiology - viral shedding in the stool can persist for weeks and therefore isn’t a reliable tool

Viral serology (IgM)
- useful for causes that are not commonly seropositive
- Serum titers of antibodies against HIV

53
Q

Do not use viral serology in viral meningitis for what viruses?

A

HSV, VZV, CMV, and EBV
frequently seropositive

54
Q

imaging for viral meningitis

A

Neuroimaging

  1. CT/MRI is not necessary in uncomplicated
  2. Indications include:
    - altered LOC
    - seizures
    - focal neurologic s/s
    - atypical CSF profiles
    - underlying immunocompromising treatments or conditions
55
Q

management for viral meningitis

A
  1. Empiric abx/antivirals for:
    - elderly
    - immunocompromised
    - strong early suspicion of bacterial meningitis
  2. IF dx INDETERMINATE after CSF eval
    - empiric abx after blood and CSF cx OR
    - observe (w/o abx) and repeat LP in 6-24 h
  3. d/c Empiric if pt is improving and (-) cx
  4. Most self limited and tx is supportive
  5. based upon etiology:
    - HSV - IV acyclovir (dose based upon weight)
    — Newborn - 3 mo - 21 d
    — +3 mo - 10-21 d
    - VZV (severe) - IV acyclovir - 10-14 d
    - HIV- consult ID
56
Q

course and prognosis Viral Meningitis

A

MC self limited course - 7-10 days without specific therapy
Can be fatal or associated with significant morbidity in neonates

57
Q

prevention of viral meningitis

A

Vaccination

poliovirus (IPV)
mumps, measles, rubella (MMR)
varicella (VAR/Zoster)

58
Q

what is meningoencephalitis?

A

Encephalitis with meninges involved

59
Q

what is encephalomyelitis/encephalomyeloradiculitis

A

Encephalitis when spinal cord/nerve root involved

60
Q

cause of encephalitis

A

MC viral

  1. MC - herpesviruses (HSV, VZV, EBV)
  2. Other: enteroviruses, measles, mumps, rubella, rabies virus, human herpesvirus 6¹, arthropod-borne viruses
  3. Other - less common
    - autoimmune encephalitis - autoimmune antibodies found in serum or CSF
    - amebic encephalitis - motile trophozoites seen in wet mount of warm, fresh CSF
    - parasitic - toxoplasmosis
61
Q

presentation of Encephalitis

A
  1. Fever
  2. HA, N/V
  3. Seizures
  4. Altered LOC - mild lethargy to coma
  5. Psychotic sx - hallucination, agitation, personality/behavioral changes
  6. Focal neurologic signs - Speech/hearing problems, CN deficits, involuntary movements (e.g. tremor, myoclonic jerks), muscle weakness, partial paralysis in UE/LE, memory loss
  7. Occasional involvement of HPA axis may result in:
    - temp dysregulation (hypothermia)
    - Diabetes Insipidus
    - SIADH
  8. Neonatal (0-28 d)/young infant
    - fever
    - poor feeding
    - irritability
    - seizure
    - decreased perfusion - slow cap refill, cool extremities, decreased urine output, decrease level of alertness
  9. Findings indicative of:
    - HSV infections in neonates - herpetic lesions, keratoconjunctivitis, oropharyngeal lesions
    - meningitis = signs of meningeal irritation
62
Q

work-up/labs for encephalitis

A
  1. LP w/ CSF analysis - same as bacterial meningitis
    - results same as viral meningitis
  2. CSF PCR amplification - primary diagnostic test
    - CSF PCR for each individual virus has to be ordered
63
Q
  1. work-up/imaging for encephalitis?
  2. results?
A
  1. MRI/CT brain and EEG
    - MRI sensitive > CT
    - “Focal” findings = HSV
    - HSV encephalitis = EEG abnormalities
  2. Brain bx
64
Q

indications for brain bx for encephalitis

A
  1. focal abnormality on MRI
  2. negative CSF analysis/PCR
  3. progressively deteriorate despite tx with acyclovir and supportives
65
Q

additional labs for encephalitis

A
  1. CBC - often unremarkable
  2. CMP
    - lyte abnormalities if dehydration or SIADH
    - glucose - compare to CSF glucose and r/o hypoglycemic presentation
    - BUN/Cr - assess hydration status, end-organ damage and renal function for med dosing adjustments
    - LFT - assess for end-organ damage, med adjustment
  3. PT/PTT - assess bleeding disorders/complications, helps determine the need for transfusion of FFP or platelets
  4. Blood cx
  5. Viral cx and Tzanck smear - herpetic lesions
66
Q

you get an MRI/CT for suspected encephalitis but results show a space occupying lesion, what is this dx now?

A

brain tumor/abscess

67
Q

how can you assess for autoimmune encephalitis?

A

assess specific autoantibodies in serum/CSF

68
Q

what factors would make you feel more suspicious of amebic infection instead of encephalitis?

A
  1. Hx of exposure to warm, iron-rich pools of water, including those found in drains, canals, and both natural and human-made outdoor pools
  2. CSF analysis resembles bacterial meningitis
  3. motile trophozoites are seen in wet mount of fresh warm CSF
69
Q

an immunocompromised pt that has a cat is suspected to have encephalitis, but what else could be in your ddx?

A

Toxoplasmic/cryptococcal neuroinfection

70
Q

tx for Encephalitis

A
  1. Continuous monitoring and tx abnormal VS - rsp support, fluids
  2. Seizures - IV lorazepam
    - secondary prevention - phenytoin or/fosphenytoin
  3. Increased ICP - neuro checks
    - look for deterioration or change in neuro status
    - elevate head of bed, control F and pain, control of straining and coughing, prevent seizures and significant hypo/HTN
  4. Empiric : IV acyclovir x 21 d
    - Adults/Pediatric
    - for all pts as a ddx
    — Only HSV and severe VZV/EBV encephalitis get definitive antiviral therapy
    - Lab specimens and blood cx obtained prior to first antiviral dose
  5. Empiric abx if bacterial meningitis is in the ddx
71
Q

what are neuro checks?

A
  1. Assess level of consciousness
    - full consciousness, lethargy, obtundation, stupor, coma
  2. Perform an A/O and compare with the patients baseline
  3. Perform a pupil check
  4. Assess facial symmetry
  5. Perform tongue midline
  6. Assess patient’s speech clarity for slurs, impediments or incoherence
  7. Assess sensation - observe physical response, sensitivity to touch and check for numbness or lack of movement
  8. Assess grasp strength
  9. Assess strength and ROM of UE and LE
72
Q

First dose of empiric antiviral tx should be administered to pts with potential viral encephal within how long of arrival to ED?

A

30 minutes

73
Q

what should be repeated at the completion of antiviral therapy in those patients who were PCR (+)?

A

CSF analysis for PCR
If remains positive additional antiviral therapy should be given

74
Q

Complications to watch for and attempt to prevent in Encephalitis:

A
  • aspiration pneumonia, stasis ulcers/decubitus, contractures, DVT/PE, infections of indwelling lines/catheters
  • Sequelae:
    Seizure disorder
    Cognitive impairment
    Movement disorders
    tremor, myoclonus, parkinsonism
    Hemiplegia
75
Q

difference between encephalitis vs meningitis?

A

Presence or absence of normal brain function is the most important distinguishing feature between the two

  1. Meningitis - uncomfortable, lethargic or distracted by HA but CEREBRAL FUNCTION is generally intact
  2. Encephalitis- HAS abnormalities in brain function:
    - Altered mental status
    - Motor and sensory deficits
    - Altered behaviour and personality changes
    - Speech and movement disorders
76
Q

Patient Education to Avoid Transmission of All CNS Infections

A
  1. Avoid sharing food, utensils, drinks and other objects with person exposed to or has infection
  2. Wash hands with soap and water
  3. Keep vaccinations UTD
    - H. flu, Pneumococcal, N Meningitidis
  4. Prophylactic tx of those exposed
  5. Reduce exposure to infected arthropods
77
Q

an uncommon focal, suppurative infection within the brain parenchyma and surrounded by a capsule

A

Brain Abscess

78
Q

a non-encapsulated abscess is referred to as ?

A

cerebritis

79
Q

risk factors/causes of brain absceses?

A
  1. Direct spread
    - otitis media, mastoiditis (33%)
    - paranasal sinusitis (10%)
    - dental infections (2%)
  2. Hematogenous spread (25%)
    - pyogenic infections (anywhere in the body)
  3. Trauma/Surgery (30%)
    - penetrating head trauma
    - neurosurgical procedures

In 25% of patients no obvious cause is identified

80
Q

presentation of brain abscess?

A
  1. HA - MC sx (>75%)
    - onset: gradual, 10 d after onset of sx
  2. Focal neurologic deficits (>60%)
    - hemiparesis
    - aphasia/dysphasia
    - nystagmus/ataxia
  3. Fever (50%)
  4. New onset seizure (15-35% of patients)
  5. S/S of increased ICP
    - papilledema, N/V, change in LOC, confusion
81
Q

pt with suspected brain abscess is having hemiparesis, which part of the brain is involved?

A

frontal lobe abscess

82
Q

pt with suspected brain abscess is having aphasia/dysphasia, which part of the brain is involved?

A

temporal lobe abscess

83
Q

pt with suspected brain abscess is having nystagmus/ataxia, which part of the brain is involved?

A

cerebellar abscess

84
Q

work up for brain abscess?

A

Dx is made by imaging studies

  1. MRI or CT w/ contrast
    - MRI more sensitive > CT BUT not as readily available
  2. Routine serology
    - CBC - elevated WBC
    - CMP - assessing renal and liver function
    - Blood cx x 2 - preferably before first abx dose
  3. CT/MRI-guided stereotactic needle aspiration
    - C&S of abscess aspirate to guide therapy
85
Q

upon CT w/ contrast shows a focal area of hypodensity surrounded by ring enhancement with surrounding edema

what this be

A

brain abscess

86
Q

upon a MRI w/ contrast shows a capsule that enhances surrounding a hypodense center and surrounded by a hypodense area of edema

what this be

A

brain abscess

87
Q

ddx if there is a fever present with brain abscess?

A

subdural empyema, bacterial/viral meningitis/encephalitis, superior sagittal sinus thrombosis

r/o after imaging is obtained

88
Q

ddx if no fever present with brain abscess?

A

primary/metastatic brain tumor
imaging can differentiate abscess vs solid tumor

89
Q

tx for brain abscess

A
  1. High dose empiric parenteral abx AND neurosurgical drainage
    - Community - ceftriaxone + metronidazole
    - hx of head trauma or recent neurosurgery - ceftazidime + vanc OR
    meropenem + vanc
  2. Steroids ONLY if there is peri-abscess edema w/ associated mass effect and increased ICP
  3. seizure prophylaxis
  4. abscess drainage if indicated
  5. Complete excision ONLY IF recommended
90
Q

Abscess drainage is recommended for all pts with brain abscesses EXCEPT:

A
  • abscess is neurosurgically inaccessible
  • small (<2–3 cm) or non-encapsulated abscesses
  • unstable
91
Q

complete excision of brain abscess if recommended ONLY if?

A

abscess is multiloculated or aspiration fails

92
Q

management/clinical course of brain abscess?

A
  1. Minimum of 6–8 wks of parenteral abx
  2. Serial MRI/CT monthly or twice-monthly basis
  3. Prophylactic anticonvulsant x 3 mo
    - can be d/c once EEG is normal both pre- and post medication withdrawal
93
Q

poor prognostic signs for brain abscesses

A
  1. Rapid progression of the infection before hospitalization
  2. Severe mental status changes on admission
  3. Stupor or coma (60-100% mortality)
  4. Rupture into ventricle (80-100% mortality)

Sequelae occur in ≥20% of survivors
seizures, persisting weakness, aphasia, or mental impairment

Neuro: Clin Med IIB (13 decks)

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