Meningitis Flashcards
Typical CSF Findings in patients with Bacterial meningitis
i) High WBCs (mostly PMNs)
ii) High Protein
iii) Low Glucose
Typical CSF Findings in patients with Viral meningitis
i) High WBC
ii) High protein
iii) Normal Glucose
a) Fever, headache, and photophobia less neck stiffness and altered mental status
b) Incidence highest during first year of life
c) CSF increase in lymphocytes and monocytes, slight increase in protein, and normal glucose.
d) PCR confirmation- not necessary.
e) Supportive therapy and recover on their own, but can be fatal in neonatal period
10) Aseptic Meningitis Syndrome (often Viral but could be noninfectious including some antibiotics TMP-SMX)
11) >85% of viral meningitis are associated with
enteroviruses
a) “pico” for small, “rna”
b) summer and fall
c) Transmitted hand to mouth
d) Genome organization
e) Single stranded
f) (+) sense RNA
g) Capsid symmetry
h) Icosahedral
i) No Envelope (Naked)
12) Enterovirus/Picornavirus Coxsackie, ECHO viruses
a) Fever, stiff neck, irritability, and neurologic dysfunction.
b) Acute onset and progression.
c) Big three:
i) Streptococcus pneumonia (pneumococcal)
ii) Neisseria meningiditis (meningococcal)
iii) Haemophilus influenza type b
d) Meningeal inflammation associated with inflammatory exudate in the CSF containing many polymorphonuclear leukocytes, increased protein, and decreased glucose.
e) Life-threating and requires prompt empiric antibiotic therapy.
13) Septic Meningitis (Bacteria)
14) Bacterial meningitis treatment
a) Immediate empiric treatment with Ceftriaxone or cefotaxime
– 3rd gen cephalosporins, beta-lactam
a) Mechanism: Bind to penicillin binding proteins (transpeptidases) to inhibit cell-wall synthesis
b) Spectrum: Broad, used for streptococci and more serious Gram- infections, Can cross blood brain barrier
c) Resistance: inactivation of the drug by beta-lactamases, change in penicillin binding protein
d) Side effects: allergies, seizures
15) Ceftriaxone
a) Endotoxin is shed from outer cell membrane of Gram negative bacteria
b) Neisseria meningitides structure slightly different called lipooligosacchride (LOS), which mimics brain sphingolipids so recognized as self
c) LPS activates macrophages leading to release of NO(hypotension, Shock) and IL-1(fever), and can activate disseminated intravascular coagulation leading to purpuric skin rash.
18) Lipopolysaccharide
a) Gram negative, diplococcus
c) Virulence factors include pili, IgA protease, capsule, and endotoxin
e) Transmit through respiratory droplets
f) LOS leads to thrombocytopenia, associated with disseminate intravascular coagulation leading to hemorrhagic skin rash- doesn’t fade under pressure.
g) Definitive and prophylactic treatment with ceftriaxone
19) Neisseria meningitidis -Meningococcal meningitis
a) Gram positive diplococci, lancet shape
b) Transmitted through respiratory droplets
c) Meningitis is secondary to paranasal sinusitis and otitis media
d) Most common cause of meningitis > 2 months old
f) 19A-resistant S. pneumoniae treat with vancomycin
g) Heptavalent protein-conjugate vaccine
20) Streptococcus pneumonia- Pneumococcal meningitis
a) Gram- “Coccoid” rod
b) Disease occurs in unvaccinated infants and young children.
c) Virulence factors include pili, outer membrane proteins, IgA protease and endotoxin.
e) Prevention with Hib vaccine- B capsular polysaccharide.
21) Hemophilus influenza type b
a) Gastrointestinal and genitourinary tract flora
b) Vertical transmission to infant: in utero or during vaginal delivery
c) given Penicillin G as prophylactic
g) Bacitracin resistant, catalase negative, CAMP reaction (synergistic hemolysis of red blood cells by phopholipase of GBS and B-hemolysin of S. aureus)
23) Group B streptococcus aka Streptococcus agalactiae
Gram negative, rod
a) Infants, immunocompromised
b) Enteric organism, bacteremia, and transcellular permeation of blood brain barrier
c) LPS, K1 capsular polysaccharide prevents fusion with lysosome
d) If expressing beta-lactamase, ceftriaxone may not be sufficient switch to carbapenem
24) Escherichia coli K1 strains- Gram negative, rod
Gram positive, rod
a) Immunosuppressed, pregnancy, older adults, newborns
b) Consumption of contaminated food- unpasteurized milk, cheese, and deli meats
c) Fever, headache, no nuchal rigidity, diarrhea
d) Intracellular bacteria, internalin induces phagocytosis by epithelial cells of intestine, phospholipase and listeriolysin O allow escape from vacuole, actin tails facilitate spread between adjacent cells.
e) 50% of blood tests come back negative
f) Definitive therapy with Ampicillin + Gentamicin for 3 weeks.
25) Listeria monocytogenes
