Listeria monocytogenes spread - Answer-Invade non-phagocytes (InIA - E Cadherin)
-Lyse the phagosome (Listeriolysin O [LLO])
-LLO toxin enters the cytoplasm
-Utilize host actin to spread from cell-to-cell
Invade through the mucosal surface into the bloodstream (septicemia)
Cross the BBB (inflammation causes BBB permeability)
How does Listeria monocytogenes escape host defenses? - Answer--Intracellular
-Infects macrophages (escapes vacuole)
-Peptidoglycan deacetylation (TLR-2)
How does Listeria monocytogenes cause damage in bacterial meningitis? - Answer--
Inflammation (triggered by peptidoglycan)
-Fluid accumulation
-Increased intracranial pressure
-Hydrocephalus and brain damage (permanent)
OUTCOMES
HIGHLY LETHAL IF NOT TREATED
, NON-COMMUNICABLE EXCEPT FOR MOTHER TO BABY
Haemophilus influenzae Type B - Answer--Gm(-) rod
-Encapsulated (Type B antigen)
-All other types are less likely to causes disease
-Primary cause of bacterial meningitis in children 6 months to 2 years
-Vaccine available (almost eliminated it)
-
HiB encounter - Answer--Humans only
-Respiratory droplet or saliva
-Can be endogenous (sets up shop slowly)
HiB spread - Answer-Invade from URT into blood, then cross the blood-brain barrier to
CNS
HiB growth requirements - Answer-Fastidious, requires chocolate agar
How does HiB evade host defenses? - Answer--Extracellular
-Capsule
-Phosphorylcholine decoration of LOS (tricks anti-LOS IgG)
-Sialylation of LOS
-Binds complement factor H
-IgA protease
How does HiB cause damage to host? - Answer--Inflammation
-LPS
-Protein D - ciliated epithelium (glycerophosphodiesterase)
HiB infection outcomes - Answer--Death
-Neurological sequellae
-Transmission to new host (droplet/saliva)
HiB vaccine - Answer--Humoral IgG against capsule prevents systemic infection by
opsonization
-Composed of type B carbohydrate coupled to protein
-Drastically reduced meningitis by HiB
-Single serological type of capsule makes vaccination easier and more effective
-Part of the standard infant/childhood regimen
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller Perfectscorer. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $12.49. You're not tied to anything after your purchase.
