Infectious Disease Flashcards
What three vaccines have led to a decrease in incidence of meningitis?
Hemophilus Influenza B
Pneumococcus
Meningococcus
Meningitis is an infection of the __________ space.
subarachnoid
Infection of the subarachnoid space leads to __________.
cerebral edema
The classic signs and symptoms of meningitis are ___________.
fever, headache, nuchal rigidity, and depressed consciousness (100% have at least 2 of these; 40% have three)
What is the mortality of bacterial meningitis?
20%
The first step in managing suspected meningitis is ___________.
starting antibiotics (preferably within 60 minutes)
The definitive diagnostic procedure for diagnosing meningitis is __________.
lumbar puncture
CSF signs of meningitis are ___________.
pleocytosis, neutrophils greater than 80%, glucose less than 40 mg/dL, high protein, and culture/Gram stain
What is papilledema?
Bulging of the optic disk in the eye (a sign of increased ICP)
What are the most common bacterial species that cause neonatal meningitis?
- Group B Streptococcus (50%)
- Escherichia coli (14%)
- Streptococcus pneumoniae
- Neisseria meningitidis
What are the most common bacterial species that cause infant-toddler meningitis?
Strep pneumo
N meningitidis
Group B Strep
What are the most common bacterial species that cause adult meningitis?
2-35:
- Neisseria meningitidis (50% - 60%)
- Streptococcus pneumoniae
Older than 35:
- Streptococcus pneumoniae
Research indicates that, in addition to antibiotics, _________ should also be given with or before the first antibiotics.
Corticosteroids (to decrease inflammation-related injuries)
Altered conscious happens in ________ bacterial meningitis.
advanced
What patients have atypical presentations of meningitis?
Infants and the elderly
What is the most common mechanism that bacteria enter the meninges?
Hematogenously (less common are through adjacent infections and penetrating trauma)
When should you not do an LP immediately?
Focal neurologic deficit Papilledema Prior CNS issues Seizures Decreased level of consciousness Immunocompromised
What is the normal CSF protein for adults and children?
Less than 50 for adults and 150 for children
True or false: those with brain abscesses present with high CSF WBC.
False (because the white blood cells stay in the abscess)
What antibiotics should be given to neonates with suspected meningitis?
Ampicillin
Cefotaxime / aminoglycoside
What antibiotics should be given to people in the 3 month to 50 year age group?
Ceftriaxone or cefotaxime
Vancomycin
What antibiotic should be given to the elderly with suspected meningitis?
Ampicillin
Vancomycin
Ceftriaxone
What antibiotics should be given to immunocompromised patients with suspected meningitis?
Ampicillin
Meropenem / cefepime
Vancomycin
Which bacterial species require the longest treatment plans?
Gram-negative bacteria and listeria
Which strain of bacterial meningitis has been shown to benefit the most from steroid treatment?
Strep pneumo
The three most common viruses that cause meningitis are ______________.
HSV-2
WNV (seasonal fall/summer)
Enterovirus (seasonal fall/summer) (80%)
What CSF finding can indicate arbovirus (besides PCR)?
elevated IgM
What clinical feature distinguishes encephalitis?
Neurologic impairment
What two viruses cause the most mortality from encephalitis?
HSV-2 and WNV
If a patient has hyperglycemia and suspected meningitis, what formula should be used to calculate their CSF glucose?
CSF:serum should be greater than 0.4 (if it is less, suspect bacterial meningitis)
Listeria is Gram ___________.
positive
What big outcome has steroid treatment been shown to prevent in developed countries?
Hearing loss (CN VIII palsy)
HSV-1 is more likely to cause ____________.
encephalitis
What is a non-cerebral sign of enterovirus infection?
Pharyngitis with macular rash
Having antibodies to NMDA can mimic ______________.
viral encephalitis (so test the CSF for the antibody; if positive, immunosuppression is the treatment)
True or false: most HSV encephalitis is primary.
False –most results from reactivation
What is the etymology of arbovirus?
ARthropod-BOrne virus
Most people with WNV display what symptoms?
Trick question… None! 80% are asymptomatic
What is the MRI pattern of WNV?
Early: normal
Late: deep-brain nuclei affected
Toxoplasmosis can lead to __________ in the brain.
cysts
Describe the findings associated with cryptococcal meningitis infection.
Few lymphocytes
Elevated protein
