Bacteria Ch 24-29 Spirochetes- Mycoplasma Flashcards
describe the microbe treponema pallidum
- gram negative spriochete but no LPS
- flagella in an axial filament between inner and outer membrane
how is treponema pallidum transmitted
- sexual and congenital transmission in body fluids and mucous membranes
-fragile
what causes disease symptoms in treponema pallidum infections
host response
what disease does treponema pallidum cause
syphilis
what are the stages of syphilis
- local: hard chancre/ulcer at site of infection; infectious
2. disseminated: rash, aches; mucous membrane lesions; infectious
3. gummas: damage to blood vessels, eyes, CNS; insanity, not infectious
what is primary syphilis and how long does it last
2-6 weeks
- chancre, which heals spontaneously, giving salse sense of relief
how long does the asymptomatic period of spyhilis last
2-24 weeks
what is secondary syphilis and how long does it last
-2;6 weeks
-symptoms resolve spontaneously but 25% recurrence in a year
what percentage of primary syphilis infections go onto secondary
50%
microbe persists for _____ of secondary infections with _____ exhibiting tertiary syphilis
2/3; 1/2
what is tertiary syphilis
diffuse, chronic inflammation
when do gummas form
in tertiary syphilis
what is a gumma and where is it found
granuloma lesion = inflammatory mass which can perforate
- can be found on roof of mouth or any other tissues
how is congenital syphilis preventable
penicilin treatment early in pregnancy
when is syphilis highly lethal
- in utero
- when born without symptoms: high lethality typical of young children with facial and dental abnormailities like hutchinsons incisors or mulberry molars
when in penicilin used to treat syphilis infections
in primary or secondary infections
what is the vaccine for syphilis
there is none
describe the microbe borrelia
gram negative spirochete
what microbe causes lyme disease
borrellia burgdoreferi
what animal hosts borrelia burgdorferi
ixodes scapularis tick
when is lyme disease risk the greatest
in spring and summer
what is the mode of transmission for lyme disease
-ticks
- reservoir: rodents, deer
what are the symptoms of acute lyme disease
-local- fever
what are the symptoms of disseminated lyme disease and when does this occur
- nerve paralysis with heart arrhythmia
2-8 weeks
what are the symptoms of chronic lyme disease and when does this occur
arthritis, CNS paralysis due to persistent immune response
- more than 6 months
what is the vaccine for lyme disease
there is none
what is the virulence factor for borrelia spp
- antigenic variation
- surface binding proteins
what is the vaccine for relapsing fever
none
what microbes cause relapsing fever
-B. recurrentis
- B. miyamotoi
what are the clincial features of borrelia spp
lyme disease and relapsing fever
describe the microbe rickettsia
- gram negative
- obligate intracellular parasite
- causes vascular hemorrhages
what are the virulence factros for rickettsia
- intracellular growth and rapid cell to cell spread from cell projections by actin rockets and through cell lysis
how is rickettsia transmitted
-wood tick
- reservoir: wild rodents
what diseasedoes rickettsia cause
rocky mountain spotted fever
what type of disease is rocky mountain spotted fever
CTL immune disease
describe rocky mountain spotted fever
- rash of extremities, then trunk
- hemorrhagic lesions with disseminated vascular CTL lysis of endothelial cells -> spots
- dissemination to heart, kidneys -> shock and death
what is the mortality percentage for rocky mountain spotted fever if untreated
20-40%
what is the treatment for rocky mountain spotted fever
doxycyline or fluoroquinolones
what is the vaccine for rocky mountain spotted fever
none
describe the microbe chlamydia trachomatis
-gram negative
- obligate intracellular parasite
- no peptidoglycan synthesis
what disease does chlamydia trachomatis cause
chlamydia
what is the most frequent STI and what are the next 3
chlamydia trachomatis, then gonorrhea, AIDS and syphilis
what causes disease manifestations in chlamydia trachomatis
inflammatory cytokines released from infected cells
what are the 2 identification methods for chlamydia trachomatis
iodine or specific fluorescein- labeled antibodies
what is the mechanism of action of chlamydia trachomatis
EB: epithelial cell adhesion to microvilli -> RB in phagosomes -> replication and division -> EB -> cell lysis/exocytosis
what are EB and RB in chlamydia trachomatis
- EB: elementary body, stable, infectious
- RB: reticulate body, replicating, fragile, non infectious
describe the gonorrheal like sexual disease caused by CMI responses
- 8 serotypes
- mucopurulent urethritis, cervicitis, salpingitis
- mobility by adhesion to sperm -> PID -> scarring -> ectopic pregnancy
and decreased fertility
how many serotypes are there in lymphogranuloma venereum
3
how mnay serotypes are there in trachoma and what are the symptoms
-4
- endemic chornic eye infection, blindness
- opthalmia neonatorum with conjunctivitis and pneumonia
do you get immune protection from chlamydia infection
none
what happens with reinfection of chlamydia
stronger CMI
what causes walking pneumonia
C. pneumoniae
what is the leading bacterial infection in the US
chlamydia
describe mycoplasma pneumoniae
- non gram staining, strong membrane
- no sterilization by filtration
- mycoplasma species are smallest prokaryote
- strict aerobe
what are the virulence factors for mycoplasma pneumoniae
-P1 adhesin for ciliated respiratory epithelium: loss of ciliated cells: no mucus clearing from lungs
- slow growth
is there a vaccine for mycoplasma pneumoniae
no
is there immunity after an infection from mycoplasma pneumoniae
fading protective immunity after recovery
describe the disease caused by mycoplasma pneumoniae and the transmission
-atypical, mild pneumonia
- the leading cause in schools, students and military
- aerosol transmission in crowded conditions
what are the available vaccines for pneumococcal pneumonia, kiebsella pneumonia, and mycoplasmal pneumonia
-pneumococcal pneumonia: capsular vaccine availble
- kiebsella pneumonia: none
-mycoplasmal pneumonia: none
what is the simplest free living bacterium
mycoplasma genitalium
what is known as walking pneumonia and why
mycoplasma pneumonia because it is mild and does not require hospitalization
