ID Emergencies Flashcards
Meningitis
- Meninges are made up of what? 3
- Meningitis affects which parts of the brain? 3
- Meninges is made up of the
- pia,
- arachnoid
- dura maters - Meningitis affects the
- arachnoid,
- subarachnoid space and
- CSF
Etiology for meningitis
- MC bacterial causes? 3
- MC viral causes? 6
- MC fungal causes? 1
- MC noninfectious causes? 5
- Bacterial
- Streptococcus pneumoniae
- Neisseria meningitidis
- Haemophilis influenzae - Viral
- Enteroviruses,
- HSV,
- HIV,
- West Nile,
- VZV,
- mumps - Fungal
- Cryptococcus (most common) - Noninfectious
- Tumor,
- trauma,
- brain abscess,
- subdural empyema,
- pharmacologic reaction
Can be community acquired or healthcare associated
- Community acquired? 4
- Healthcare associated? 2
- Community acquired
- Streptococcus pneumoniae
- Neisseria meningitidis
- Haemophilis influenzae
- Listeria monocytogenes (immune compromised) - Healthcare associated
- Staphlococci and
- aerobic gram negative bacilli
Meningitis symptoms
- Onset?
- Classic triad?
- Other symptoms? 7
- Median duration of symptoms before presentation?
- What is petechial rash associated with?
- Abrupt onset
- Classic triad:
- fever,
- nuchal rigidity,
- change in mental status - -Intense headache
Other symptoms:
-photophobia,
-lethargy,
-nausea,
-vomiting,
-joint pain,
-seizures - Median duration of symptoms before presentation 24 h (bacterial)
- Petechial rash is associated with N. Meningitidis
Diagnosing CNS infections in the elderly
- Difficult to initially separate meningitis from what?
- Both present with what?
- Elderly with meningitis are less likely to have what symptom?
- Any infection can cause what in the elderly?
- Red flags? 5
- encephalitis
- both present with mental status changes
- elderly with meningitis less likely to have fever
- Any infection can cause delirium in the elderly
- Red flags:
- Behavioral changes/personality changes
- Seizures
- Lack of other source of infection
- Headache, nuchal rigidity, exposure to infected persons
- Low threshold to do LP
Who needs a head CT prior to LP?
Proceed to head CT prior to LP if any of the following are present at baseline:
4
- Immunocompromised
- History of seizure within one week prior to presentation
- Any of the following neurologic abnormalitie
- Mandatory in patients with possible focal infection
Who needs a head CT before the LP: Any of the following neurologic abnormalities? 5
- Abnormal level of consciousness
- History of CNS disease (mass lesion, stroke, or focal infection)
- Papilledema
- Abnormal level of consciousness
- Focal neurologic deficit
Lumbar puncture in meningitis
1. Any evidence of papilledema or focal neuro findings, DO NOT perform LP before you get a STAT CT to rule out what?
- Perform LP immediately in the absense of what? 2
- significant ICP (or herniation of brainstem may occur during LP)
- Papilledema
- Focal neuro findings
Meningitis work up
5
- Blood cultures, CBC, and Chem 7
- Send CSF to lab for cell count, gram stain, culture, glucose and total protein
- As soon as LP is completed (before labs are even back) give 2 G Rocephin (Ceftriaxone) IV
- All are admitted and Rocephin is continued at 2G IV q12h
- Many even with proper, rapid treatment will die or have permanent CNS deficits
Send CSF to lab for cell count, gram stain, culture, glucose and total protein
- Any what on gram stain is diagnostic?
- What WBC count is diagnostic for meningitis?
- CSF glucose less than what is suggestive?
- ANY (+) Gram stain is diagnostic
- WBC in CSF > 1000 if PMNs make up 85% is diagnostic
- CSF glucose less than 50% of serum glucose is suggestive
CSF Normal Values
- Pressure?
- Appearance?
- CSF total protein?
- CSF glucose?
- CSF cell count?
- Chloride?
- Pressure: 70 - 180 mm H20
- Appearance: clear, colorless
- CSF total protein: 15-45 mg/100 mL
- CSF glucose: 50-80 mg/100 mL (or greater than 2/3 of blood sugar level)
5, CSF cell count: 0-5 white blood cells (all mononuclear), and no red blood cells - Chloride: 110-125 mEq/L
Pediatrics:
- Bacterial meningitis occurs more frequently between age?
- Uncommon to develop meningitis from OM and spread is not from direct extension but from what?
- What may be the only clues in young infants? 2
- Paradoxical irritability is suggestive of meningitis. What is this?
- 2 months-2 years
- systemic spread
- Irritability
- poor feeding
- (crying worsens when being held)
Most common meningitis etiologic agents in pediatrics
- MC? 3
- In neonates?
- Primary prevention of meningitis? 3
- Streptococcus pneumoniae (pneumococcus)
- Neisseria meningitidis (meningococcus)
- H. influenzae Type B (due to the vaccine now is a rare cause but used to be the most common)
- In neonates consider gram – causes and Group B Strep
- Primary prevention of meningitis
- S. pneumoniae vaccine
- H. influenzae vaccine
- Meningococcal vaccine is available for adolescents and adults
What are the following lab values for the normal CSF fluid:
- White cells?
- % neutrophils?
- CSF Glucose?
- Blood glucose?
- Protein?
- 5
- 1%
- 65
- 85
- 21
Normal. The normal number of WBCs in the CSF depends upon the age of the patient. The younger and more immature the infant is, the high the value is. CSF glucose vale depends upon the value of glucose in the blood and upon the integrity of the blood brain barrier. In pts with normal meninges the CSF value is usually about 75% of the blood level. When the meninges become inflamed, the active transport of glucose across the blood brain barrier becomes altered an dthe ratio drops proportionately to the degree of inflammation. Most viral meningitis produce less chanes than bacterial meningitis accordingly CSF glucose values are lower in bacterial meningitis.
What does the following LP suggest?
- White cells- 1243?
- % neutrophils-94%?
- CSF Glucose- 23?
- Blood glucose- 78?
- Protein-62
Bacterial Meningitis
Bacterial. Cases of early viral meningitis can present with an increased number of cells and neutrophils but usually the CSF glucose is normal or not lower than 40% of serum glucose.