141 - Encapsulated bacteria

First Aid
What does it means if a bacteria is encapsulated?
It has a tough polysaccharide coat on the outside. It is a virulence factor that helps resist phagocytosis.
What is the relationship between asplenia and encapsulated bacteria?
People with asplenia (frank or functionally via disease) are more susceptible to infection by encapsulated bacteria.

Therefore, asplenic patients are vaccinated against Neisseria meningitis, Haemophilus influenzae, and Streptococcus pneumoniae.

These vaccines can be remembered with the mnemonic: NHS.

These three are also important because they produce IgA protease, cause meningitis, and take up DNA from the environment for transformation.
What is a Quellung reaction?
"Quellung is German for swelling."

When antibodies bind to bacterial capsular antigen, the capsule appears to swell. The swelling allows these organisms to be visualized with microscopy.
Name the classic encapsulated bacteria
"GBS Kapsules Shield SHiN"
Note that SHiN is the same as NHS
Group B strep (Streptococcus agalactiae)
Klebsiella pneumoniae
Streptococcus pneumoniae
Haemophilus influenzae - Type B
Neisseria meningitidis
There is some stuff in this section about using bacterial capsules as part of conjugate vaccines... but i don't get it. Came back after immunology.