the actually part 2 medically important Flashcards
most imp virulence factor of s pneumoniae
capsular antigens
what do capsular antigens do
evade phagocytosis and make specific anticapsule Ab
is there a vaccine for s pneumoniae
yes
pneumolysin causes
alpha hemolysis
what is s pneumniae susceptible to
PCN and erythromycin
vanco for severely ill pts
s pneumoniae beta lactamase producers?
no
vaccines for s pneumoniae?
Prevnar 13 and Pneumovax 23
leading cause of infectious disease in the us is from
meningitis
what 2 diseases does n meningitides aka menigococcus cause
meningitis and meningococcemia
what 4 diseases does n gonorrhea aka gonococcus cause
gonorrhea, PID, disseminated gonococcal infection (DGI), neonatal conjunctivitis
2nd MC bact disease in US
gonorrhea
tell me about neisseria
gram -
endotoxin in outer membrane (LOS)
grow on chocolate agar
oxidase +
neisseria have cytochrome C which means
turns purple or black when exposed to phenylediamine
neisseria meningitides host and transmission
humans, airbrone
where does neisseria meningitides colonize
nasopharynx
neisseria meningitides is a _____ member of the URT
transient
this is higher in ppl who live in close quarters
neisseria meningitides
this can seed the bloodstream and spread to the joints and meninges
menincogoccemia
2 organisms cause over 80% of the cases of bacterial meningitis in infants older than 2 mo
streptococcus pneumoniae, and n meningitides
MCC meningitis in ppl btwn 2 and 18
n meninitides
neisseria meningitides pathogenesis
pyrogenic
4 virulence factors of neisseria meningitides
polysaccharide capsule, endotoxin, IgA protease, FHbp (factor H binding protein)
what does LOS cause
fever, shock
what does IgA protease do?
helps bacteria attach to the membranes of the URT by cleaving secretory IgA
what does FHbp do
binds to factor H and inhibits c3b
pts with paroxysmal nocturnal hemoglobinuria taking eculizumab have 1000 * inc in this disease bc its a complement inhibitor
n meningitides
dx of meningococcal meningitis
*gram - cocci seen in smears of spinal fluid
trmt of choice for n meningitides
*ceftriaxone and penicillin G
how can we prevent meningococcal disaese
*chemoprophylaxis and immunization
ppx for meningococcal disaese
*rifampin and cipro
humans are only natural host in
n meningitis and n gonorrhea
transmission of n gonorrhea
genital tract MC, also anorectal and pharyngeal infections
mother–> newborn
n gonorrhea most important virulence factor
*pili- mediate attachment; ones without pili cant cause disease
2 virulence factors in cell wall of n gonorrhea
endotoxin LOS and outer membrane proteins
gonococci have no _____
capsules
IgA protease can hydrolyze secretory IgA which could do this in n gonorrhea
block attachment to mucosa
n gonorrhea have ____ but n meninditidis dont
pili
MCC septic arthritis in sexually active adults
disseminated infections /gonococcal bacteremia
purulent conjunctivitis AKA
ophthalmia neonatorum
trmt ophthalmia neonatorum/purulent conjunctivitis
ppx erythromycin eye ointment
what may coexist with n gonorrhea
chlamydia trachomatis
trmt uncomplicated n gonorrhea
ceftriaxone + doxycycline or azithromycin
why is doxycycline or azithromycin added to n gonorrhea
- treat any gonococcal strains resistant to ceftriaxone
2. mixed infections withchlamydia trachomatis are common
prevention n gonorrhea
condoma/barriers
contact tracing
erythromycin ointment
n gonorrhea vaccine?
none
n meningitidis vaccine?
yes
n meningitidis make beta lactamase?
no
n meningitidis ferment maltose?
yes
n meningitidis have a poysaccharide capsule?
yes
n meningitidis portal of entry
resp tract
n gonorrhea polysaccharide capsule?
no
n gonorrhea maltose fermentor?
no
n gonorrhea make beta lactamase?
some
