BACTERIAL CNS Flashcards
What constitutes CHRONIC Meningitis?
Progressive or persistent sxs for 4+ weeks
What does “aseptic” mean?
CSF cx shows no bacteria → assume viral bc cannot positively ID any bacteria but still bacterial in reality
What two populations are most affected by Meningitis
- Children
- Elderly
What types of organisms are associated with community-acquired Meningitis, and what are the three?
Organisms that colonize the respiratory tract
- S. pneumoniae
- H. influenzae
- N. meningitidis
What three pathophysiology pathways can lead to Meningitis, and which is most common?
- Invasion of blood stream and seed in CNS = MOST COMMON
- Retrograde neuron pathway
- Direct contiguous spread
What three PE findings are seen with Meningitis, and what is the reasoning behind this?
- Edema
- Increased ICP
- Altered blood flow
Due to partially disrupted BBB → “leaky” blood vessels allow fluid/WBCs/other immune components to enter brain
What is the classic triad of Meningitis?
- Fever
- HA
- Neck stiffness
What two labs should be ordered to evaluate for Meningitis?
- CBC
- Serum glucose (COMPARE to CSF glucose)
What finding is seen on CSF glucose that is + for Meningitis?
LOW CSF glucose
- Lower than serum glucose because bacteria are using glucose as a food source
What four additional symptoms are seen in Neonatal Meningitis?
- Bulging fontanelle
- High-pitched cry (scream)
- Hypotonia
- Paradoxic irritability
What PE finding is VERY common in Neonatal Meningitis?
HIGH fever (hyperthermia)
What three organisms are primarily associated with Neonatal Meningitis? Which are G+ or G-?
- Streptococcus agalactiae (G+)
- Escherichia coli (G-)
- Listeria monocytogenes (G+)
What is another name for Streptococcus agalactiae? Is it G+ or G-?
Group B Streptococcus (GBS)
- It is G+
What is the most common cause of Neonatal Meningitis?
Streptococcus agalactiae (G+) = GBS
What organism is G+ coccus with beta-hemolysis?
Streptococcus agalactiae (G+) = GBS
What organism is transmitted during delivery (or before)?
Streptococcus agalactiae (G+) = GBS
Is EARLY or LATE Meningitis due to Streptococcus agalactiae associated with maternal obstetric complications common?
EARLY Streptococcus agalactiae (G+) = GBS
Is EARLY or LATE Meningitis due to Streptococcus agalactiae associated with more severe sxs?
LATE Streptococcus agalactiae (G+) = GBS
What organisms is diagnosed via definitive = blood or CSF isolation?
Streptococcus agalactiae (G+) = GBS
What organism shows CAMP on diagnosis?
Streptococcus agalactiae (G+) = GBS
What is an important cause of NEONATAL bacterial meningitis?
Escherichia coli (G-)
What organism is transmitted via rectal colonization of mother’s vagina?
Escherichia coli (G-)
What organism is the most common cause of bacterial meningitis (in general)?
Streptococcus pneumoniae (G+)
What organism can follow pneumococcal PNA, infection at other site, or no obvious infection?
Streptococcus pneumoniae (G+)
In what two population is Meningitis due to Streptococcus pneumoniae common?
- Elderly
- Recurrent meningeal infections
What organism is G- coccobacillus, non-motile?
Haemophilus influenzae
What organism of Meningitis occurs in SUMMER?
Listeria monocytogenes (G+)
What organism of Meningitis is G+ motile coccobacillus?
Listeria monocytogenes (G+)
What organism of Meningitis can grow at high AND low temperatures?
Listeria monocytogenes (G+)
What organism of Meningitis is a facultative intracellular?
Listeria monocytogenes (G+)
What organism of Meningitis is transmitted via food (animal and human carriers)?
Listeria monocytogenes (G+)
What two virulence factors are associated with Meningitis and Listeria monocytogenes?
- Lipopolysaccharide-like Surface Component
- Listeriolysin O
What is the primary purpose of the Lipopolysaccharide-like Surface Component associated with Meningitis and Listeria monocytogenes?
Antiphagocytic
What are the three primary purposes of the Listeriolysin O associated with Meningitis and Listeria monocytogenes?
- Disrupts phagolysosome membrane
- Inhibits antigen processing
- Induces apoptosis
What two clinical presentations are often seen with Listeria monocytogenes (G+)?
- Sepsis
- Meningitis
What organism of Meningitis shows “tumbling” motility in hanging drop preparation?
Listeria monocytogenes (G+)
What organism of Meningitis involves homogenization required for tissue culture?
Listeria monocytogenes (G+)
What causes Meningococcal Meningitis? Is it G+ or G-?
Neisseria meningitidis (G-)
What organism of Meningitis is G- diplococcus?
Neisseria meningitidis (G-)
What organism of Meningitis is G- diplococcus, kidney-shaped?
Neisseria meningitidis (G-)
What organism of Meningitis involves chronic carriers, and where does it colonize?
Neisseria meningitidis (G-) - Colonized in nasopharynx
What symptom is pathognomonic for Neisseria meningitidis and Meningitis?
Widespread, fast-spreading skin rash (petechiae)
What three diagnostic tools can be used to evaluate for Neisseria meningitidis and Meningitis?
- Tumbler Test
- Chocolate agar
- Thayer-Martin agar
How can you prevent Neisseria meningitidis and Meningitis?
VACCINES
