Therapeutics ID Nelson Flashcard

Pathogens of Encephalitis

Viral

  • HSV (leading cause of severe encephalitis in all ages)
  • Enterovirus
  • EBV
  • Adenovirus
  • Arbovirus
  • HIV

 

Bacterial

Neonates: Group B Streptococcus, Listeria monocytogenes, Citrobacter

Others: Borrelia burgdorferi, Bartonella henselae, Rickettsia rickettsii, Mycoplasma pneumoniae

Clinical Presentation of Encephalitis

  • Disturbance in brain function (psychiatric symptoms, emotional lability, altered sensorum, ataxia, movement disorders, focal neurologic deficit, paresis, stupor, coma, seizures)
  • Fever
  • Headache
  • Personality change or irritability lasting for hours to days
  • Lethargy (coma, death)

Encephalitis Diagnosis

  • Lumbar puncture
  • Culture blood, urine, nasopharyngeal, and stool
  • Metabolic Screening
  • MRI
  • Serum Specimen: Mycoplasma serology

Encephalitis CNS Findings

  • CSF cell count normaly to slightly elevated
  • Protein normal to slightly elevated (high protein + polymorphonuclear pleocytosis = brain necrosis)
  • Glucose normal
  • Pleocytosis of mononuclear cells (elevated WBCs)

Encephalitis Treatment

Support Measures

  • Airway protection
  • Cerebral perfusion
  • Seizure control


Empiric Acyclovir

  • Needs to be started ASAP (better safe than sorry)
  • For HSV
  • Insufficient data to recommend for Mycoplasma treatment

Signs/Symptoms of Bacterial Meningitis

  • High fever, headache, nuchal rigidity
  • N/V, photophobia
  • Confusion, sleepiness
  • Seizures
  • Children (lethargic, irritable, vomiting, feeding poorly)

Physical Exam for Bacterial Meningitis

Kernig’s Sign

Brudzinski’s Neck Sign

 

Both will hurt if they have meningitis

Most Common Bacterial Pathogens of Meningitis

  • Streptococcus pneumoniae (#1)
  • Neisseria meningitides
  • Haemophilus influenzae type B
  • Listeria monocytogenes
  • Streptococcus agalactiae (Group B Strep.)
  • Escherichia coli or other G-

Normal CSF Lab Results

WBCs

< 5 (adults)

< 20 (newborns)

 

Diff

70% Lymphocytes

30% Monocytes


Protein

< 50

 

Glucose

2/3 serum

Bacterial Meningitis Lab Results

WBCs

400-100,000

 

Diff

80-90% Neutrophils (PMNs)


Protein

Mild to marked elevation (80-500)

 

Glucose

< 1/2 serum

Top 3 Infectious Bacteria that cause Meningitis in Neonates

  1. Group B Strep
  2. E. coli
  3. Listeria

Characteristics of Pneumococcal Meningitis

Streptococcus pneumoniae

Most Common Meningitis

 

Known to Affect:

  • Children younger than 2 yrs old
  • Adults with weakened immune systems

Causes neurologic damage (deafness to severe brain damage)

 

Characteristics of Meningococcal Meningitis

  • Highly contagious through droplets
  • Primarily children and young adults, those in close quarters, and travelers to foreign countries (West, Central, and East Africa, Pilgrimage to Saudi Arabia)

Clinical Signs of Meningococcal Meningitis

  • Petechial rash or purpuric lesions
  • Advances rapidly and can be fatal
  • Becomes limb threatening with hours

Group B Strep Meningitis

Streptococcus agalactiae

  • Most common cause of meningitis in neonates
  • Has been found in pregnant women (asymptomatic)
  • Less than half of adult cases had no underlying symptoms

Listeria Meningitis

  • Found in very young children and older adults
  • Crosses placental barrier and causes stillbirth
  • Immunocompromised at risk (except HIV)
  • Enters through GI tract (coleslaw, raw veggies, milk, cheese)

 

Aerobic G- Bacilli that cause Meningitis

In Neonates

  • E. coli and Klebsiella spp.

Head trauma or Neurosurgery Patients

  • Pseudomonas aeruginosa and others
  • MDR strains may need intraventricular doses of antibiotics

Empiric Meningitis Therapy: < 1 month

Common Bacteria and Treatment

S. agalactiae

E. coli

Listeria monocytogenes

Klebsiella

 

Ampicillin

+

Cefotaxime or Aminoglycoside

Empiric Meningitis Therapy: 1-23 months

Common Bacteria and Treatment

S. pneumoniae

Neisseria meningitidis

S. agalactiae

H. influenzae type B

E. coli

 

Vancomycin

+

Ceftriaxone or Cefotaxime

Empiric Meningitis Therapy: 2-50 yrs

Common Bacteria and Treatment

N. meningitidis

S. pneumoniae

 

Vancomycin

+

Ceftriaxone or Cefotaxime

Empiric Meningitis Therapy: > 50 yrs

Common Bacteria and Treatment

S. pnuemoniae

N. meningitidis

Listeria monocytogenes

Aerobic G- bacilli

 

Vancomycin

+

Ampicillin

+

Ceftriaxone or Cefotaxime

Empiric Meningitis Therapy: Basilar Skull Fracture

Common Bacteria and Treatment

S. pneumoniae

H. influenzae

Group A Streptococcus pyogenes

 

Vancomycin

+

Ceftriaxone or Cefotaxime

Empiric Meningitis Therapy: Penetrating Head Trauma

Common Bacteria and Treatment

Staph. aureus

Coagulase – Staph.

Aerobic G – (including P. aeruginosa)

 

Vancomycin + Cefepime, Ceftazidime, or Meropenem

 

Important to cover for MRSA and P. aeruginosa

 

Empiric Meningitis Therapy: Post-Neurosurgery

Common Bacteria and Treatment

Aerobic G- bacilli

Staph. aureus

Coagulase – Staph.

 

Vancomycin + Ceftazidime, Cefepime, or Meropenem

 

Important to cover MRSA and P. aeruginosa

Empiric Meningitis Therapy: CSF Shunt

Common Bacteria and Treatment

Coagulase – Staph.

Staph. aureus

Aerobic G- bacilli

Propionibacterium acnes

 

Vancomycin + Cefepime, Ceftazidime, or Meropenem

 

Important to cover MRSA and P. aeruginosa

Targeted Therapy for Meningitis

Streptococcus pneumoniae

Vancomycin

+

3rd Gen Cephalosporin

Targeted Therapy for Meningitis

Neisseria meningitidis

3rd Gen Cephalosporin

Targeted Therapy for Meningitis

Listeria monocytogenes

Ampicillin

OR

Penicillin G

 

Consider adding an aminoglycoside to these

Targeted Therapy for Meningitis

Streptococcus agalactiae

Ampicillin

OR

Penicillin G

 

Consider adding an aminoglycoside to these

Targeted Therapy for Meningitis

Haemophilus influenzae

3rd Gen Cephalosporin

Targeted Therapy for Meningitis

Escherichia coli

3rd Gen Cephalosporin
Antibiotic CSF Penetration: Able to achieve Therapeutic Concentrations

  • TMP/SMX
  • Rifampin
  • Chloramphenicol
  • Anti-TB

Antibiotic CSF Penetration: Not able to achieve Therapeutic Concentrations

  • Aminoglycosides
  • 1st and 2nd Gen Cephalosporins
  • Clindamycin
  • Most Anti-Fungals (Ampho B, Ketoconazole, Itraconazole)

Antibiotic CSF Penetration: Good if inflammation present

  • 3rd Gen Cephalosporins
  • Vancomycin
  • Penicillins
  • Carbapenems
  • Aztreonam
  • Fluoroquinolones
  • Anti-Virals (Acyclovir, Ganciclovir)
  • Fluconazole

3 Baseline Clinical Features Associated with Adverse Outcomes

  1. Hypotension
  2. Altered Mental Status
  3. Seizures

Length of Therapy: Neisseria meningitidis
7 days
Length of Therapy: Haemophilus influenzae
7 days
Length of Therapy: Streptococcus pneumoniae
10-14 days

Length of Therapy: Streptococcus agalaciae


14-21 days
Length of Therapy: Aerobic G- Bacilli
21 days
Length of Therapy: Listeria monocytogenes
> 21 days
In Meningitis, what criteria must be met before the patient can be considered for outpatient therapy?

  • Inpatient antibiotics for > 6 days
  • Afebrile for 24-48 hrs
  • No neurologic dysfunction or seizures
  • Clinically stable or improving
  • Home health nursing access
  • Reliable IV access
  • Daily availability of physician if needed
  • Patient and family compliance
  • Safe environment

Vaccine Prevention: Haemophilus influenzae type B
Infants
Vaccine Prevention: Streptococcus pneumoniae

Infants – haven’t completed vaccine series

Elderly – vaccine may be decreasing in effect

Vaccine Prevention: Neisseria meningitidis
Teenagers

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