micro review Flashcards
to help us destroy the shit out of this exam
If a bacteria doesn’t have a cell wall (no peptidoglycan) like Mycoplasma and Ureaplasma, what Abx will these bact be resistant to?
Beta-lactams (which inhibit peptidoglycan synthesis)
Does sporulation occur in Gram Pos or gram neg bact?
GP: aerobic bacillus, anaerobic clostridium GN: no
which cause of meningitis can be treated with a chemoprophylaxis?
N. meningitidis
defining components of Bacteria (4)
- lack membrane bound organelles 2. reproduce by division (binary division for the most part (but not chlamydia!)) 3. vary in their need for O2 (obligate aerobe, facultative anaerobe, obligate anaerobe) 4. vary in shape (bacillus, coccus, spirochete/spirillum)
Primary Syphilis: timing: manifestation: Number and location of treponemes:
timing: approx 3 wks post exposure manifestation:chancre which are hard like cartilage with a raised border near anus, penis, vagina or mouth. PAINLESS Treponemes: many at site of innoculation
Normal age/population of people with S. agalactiae meningitis
New born (think Group “B” strep for baby), coming from mother’s birth canal, and the elderly
the hematogenous spread of the bacteria that cause meningitis requires protection from what two parts of the innate immune system?
- phagocytosis 2. complement
3 stages of Syphilis (with symptoms and levels of measurable treponemes
- Primary: chancre which are hard like cartilage with a raised border near anus, penis, vagina or mouth. PAINLESS -many Treponemes at site of innoculation Secondary stage: Rash ON HANDS AND SOLES OF FEET that is scaley, mucosal lesions, lymphadenopathy - many treponemes widespread Tertiary: some people are asymptomatic (but a serological test would still show it’s there), others get neurosyphilis, cardiovascular syphillis (prob w/aortic valves) and gumma at many sites -few treponenes that are widespread
Mycoplasma and Ureaplasma are unique bacteria in that they…
don’t have a cell wall (ie no peptidoglycan) or outer membrane
Secondary Syphilis: timing: manifestation: Number and location of treponemes: how many people get it compared to primary?
timing: 2-24 weeks manifestation: Rash ON HANDS AND SOLES OF FEET that is scaley, mucosal lesions, lymphadenopathy Number and location of treponemes: many, widespread how many people get it compared to primary: 50%
are teichoic/lipoteichoic acids in gram pos (GP) or gram neg (GN)
teichoic/lipoteihoic acids: - GP: yes -GN: no
Bacterial Meningitis:
protein levels:
glocose levels:
primary WBC
other:
protein levels: VERY elevated glocose levels: reduced primary WBC: PMNs other: a gram stain shows up 60% of the time (ie you can see there are bacteria in the CSF)
Fungal Meningitis
protein levels:
glucose levels:
primary WBC:
protein levels: more elevated than viruses, not as elevated as bacteria glocose levels: down like bacterial meningitis primary WBC: elevated lymph *looks a lot more like bacterial meningitis than viral except for the type of WBC in CSF (lymph vs PMN)
why can’t chlamydia be seen on a gram stain?
because they have an outer membrane but no peptidoglycan
which bacteria are acid fast?
Mycobacteria– they have a thick, waxy cell wall!
the 3 infections shared by Chlamydia Trachomatis and N. gonorrhoeae in adults? What do they cause in new borns?
in adults: urethritis, cervicitis and PID– CT and GC in adults are clinically indestinguishable in newborns: conjunctivitis (both), pneumonia (Gonorrhoeae only)
LPS (O antigen of bacterium)/endotoxin in gram pos. vs gram neg bact.
LPS/endotoxin: GP: no GN: yes
porins present in gram pos vs gram neg bacteria?
porins: GP: no GN: yes– these regulate what can get into GN bact
what is most likely the cause of meningitis in a 3 yo from a developing country if the CSF shows small, pink, gram negative coccobacilli organisms?
HIB
is bacterial or viral meningitis more common? which is more severe?
viral is more common, bacterial is more severe