Flashcards in Micro Deck (47):
Lymphocytic Choriomeningitis Virus
Arenavirus: ambisense, RNA, enveloped
Causes febrile, aseptic choriomeningitis
Groups of bacteria causing meningitis:
Group B Strep
4 Classic Symptoms of Meningitis:
Ferments Glucose and Maltose
Difference of pathogenic vs. non-pathogenic N. meningitidis strains:
Pathogenic = Encapsulated (polysaccharide)
Neisseria needs ___ agar to grow
N. meningitidis is:
Transmitted by ____
Nasopharynx (asymptomatic carriage)
Most common N. meningitidis age range:
3 major N. meningitidis virulence factors
Lack of what complement proteins increases risk for N. meningitidis
-Bilateral destruction of adrenal glands
What can't you give for N. meningitides?
Group B Strep
Major risk group for GBS+ meningitis?
-GBS is natural flora in the vagina
B-hemolysin of S. aureus interacts w/ GBS to cause enhanced hemolysis
Hippurase test turns what color?
2 Ways to differentiate GBS and Listeria in a CSF sample
-Morphology on gram stain (cocci vs rod)
-Motility on wet mount
Strep pneumonia is most common cause of community-acquired: (4 things)
Pnemococcus causes a (low/high) inflammation meningitis
-Strong inflammatory response
-All pathogenic strains produce a pneumolysin
Pneumococcal disease also requires what kind of testing?
1st line Pneumococcus meningitis treatment is ___
If resistant, add ___
Vancomycin + ceftriaxone or cefotaxime
Resistant: add rifampin, meropenem or chloramphenicol
For which septic meningitises can you use corticosteroids?
3 routes of viral entry into CNS
80% of viral meningitis caused by:
Brudzinski's sign is:
-Guarding due to nuchal rigidity
-Neck raise --> leg raise
Distinguishing feature of encephalitis not found in meningitis
Encephalitis: intracerebral hemorrhage
What is ADEM?
-Acute Disseminated Encephalomyelitis
-postinfectious encephalitis (after VIRAL infection)
-1-2 weeks later
Herpes simple encephalitis usually affects what part of the brain?
When do you immunize someone for rabies?
-Prevents spread up into the brain
What is Pachymeninges
What is Leptomeninges
Pachy: outer layer, dura
Lepto: inner layer, arachnoid, dura
Lumbar Puncture CSF Findings in Bacterial vs Virus vs Fungal meningitis
Bacterial: high Neutrophils, low glucose
Viral: high Lymphocytes, normal glucose
Fungus: high Lymphocytes, low glucose
What do you have to worry about in terms of meningitis post-surgery?
Clinical feature that distinguishes Meningitis vs Encephalitis
confusion and/or decreased level of consciousness -->encephalitis
Pus in ____ (space) in acute bacterial meningitis
3 Complications of Bacterial meningitis:
1. Spreading to infect Virchow-Robbins (perivascular) space
2. Thrombosis of leptomeningeal vessels
3. Hydrocephalus (communicating or obstructive)
What kind of cell makes the BBB?
Astrocyte glial cells
"Worst headache in my life"
DDx: ruptured aneurysm
What kind of meningitis is usually self-limiting?
Aseptic (viral) meningitis
What is PML?
What causes it?
What can it be confused for
-Progressive Multifocal Leukoencephalopathy
-Viral by JC polyomavirus
-Can mimic MS
3 Major Patterns of Fungal Meningoencephalitis:
1. Chronic Meningitis
3. Parenchymal invasion
What 2 fungi are usually associated w/ vasculitis
Mucor (especially diabetics)
What 2 fung are usually associated w/ brain invasion?
Rabies asociated w/ this animal
Rabies encephalopathy pathopnemonic finding:
Negri bodies in brain
HIV encephalopathy has what finding: