T2 - Micro - Lecture 6, Neisseria And Chlamydia

Front 1

what immediately separates nisseria from strep/staph?

what can neisseria gonorhea cause?

Back 1

it's gram negative cocci, not gram positive. diplococci.

also, on the test now, IT'S OXIDASE POSITIVE. all neisseria are oxidase positive.

nisseria gonorhea can cause PID in women and epididymitis in men. can be asymptomatic in both men and women.

also, don't forget conjunctivitis in babies = blindness. and arthritis.

Front 2

what's the other kind of nisseria and what does it cause? how? is it capsulated? can it be prevented?

Back 2

nisseria meningococcus.

has a big capsule and a hemolysin - allows it to float around in blood and cause DIC.

also, causes meningitis.

bad because it causes massive recruitment of PMN's into the CNS, upping pressure and inflammation. that's why it's worse than viral meningitis.



yes, there's a vaccine. EXCEPT FOR CLASS B nisseria meningococcus, which uses sialic acid as a coat so you can't vaccinate against it.

it can cause arthritis.

so there's a vaccine for meningococcus (except type B), no vaccine for gonorrhea.

Front 3

what kind of cells does neisseria favor?

Back 3

non-ciliated cells. note that pathologies that cause loss of cilia can increase the chances of getting neisseria.

Front 4

what's interesting about neisseria's life cycle?

Back 4

it ends up being endocytosed from epithelial cells, though not destroyed, through the BL layer and takes up residence inside PMN's, where they live a long time.

this is why the disease involves a lot of pus.

gonorrhea = drips.

Front 5

how can you tell between pathogenic and non pathogenic neisseria?

Back 5

the pathogens are really particular - they need warm media, chocolate agar (cooked blood agar so the food is floating and easy to get),

Front 6

what are 2 differences about meningoccus?

Back 6

it likely has to travel through the blood (bacteremia) - which means it needs a fancy way to accumulate iron and out compete lactoferrin and transferrin.

also, meningococcus has a big capsule, while gonorrhea doesn't have much of one. perhaps this is why a vaccine against meningococus can be made but not against gonorrhea?

Front 7

Chlamydiae time: what organisms are in this category?

Back 7

there's chlamydae trachomatis, the sexy one.

also, chlamydiae pneumoniae. also psittaci, from birds..

but trachomatis and pneumonae are the most common.

Front 8

what kind of pathogen is chlamydia trachomatsi? what does this mean for treatment?

Back 8

obligate intracellular pathogen - so it's kinda gram negative, if it actually could be seen outside the cell. it's not.

has to be treated with antibiotics that can enter host cells.

weird thing - NO PEPTIDOGLYCAN anywhere.

Front 9

what's the life cycle of chlamydia trachomatis? what does this mean for pus?

Back 9

absorbed into cells, has the RB and EB forms (replicative and elementary bodies)

the EB form is what's transmissible.

there's really no recruitment of PMN's and so there's not much pus. they don't kill their hosts, so don' get much released in the way of cytokines.

Front 10

chlamydia vaccine?

Back 10

none. though rapid testing is now available and antiobitics that can get into host cells are quite effective.

Front 11

meningococcus and gonoccus - what are the main potential diseases? for gonooccus, can men AND women be asymptomatic?

Back 11

gonorrhea - leads to pelvic inflammatory disease.

yes, both men and women can be asymptomatic.

meningococcus - can get sepsis, meningitis, and DIC (it has hemolysin, after all).