3/8: Chlamydia, Ricketts, Spirochetes Flashcards
Chlamydia trachomatis general info
gram negative, obligate intracellular bacteria
T/F: Chalmydia trachomatis has peptidoglycan in cell wall
false
Chalmydia trachomatis has different ____ that have different ____ that cause ____
different biovars that have different tissue tropisms that cause different diseases
What are the 2 cycles of the biphasic life cycle of chlamydia trachomatis
- elementary bodies (EB) = infectious form
2. reticulate bodies (RB) = replicative form
Describe the cycle between elementary bodies and reticulate bodies. What bacteria is it associated with?
chlamydia trachomatis
TARP proteins on EB attach to target cell, induce endocytosis.
Uses STP within cell to convert to RB and grow. This prevents lysosomal fusion to phagosome.
Once threshold of RBs is reached, converts back to EB.
CPAF factor in chlamydia trachomatis regulates ____
apoptosis of the cell
CPAF releases EBs that go on to infect other cells
Chlamydia trachomatis is spread only in humans through ____ contact
direct
What is the most common bacterial STI in the world?
chlamydia trachomatis
Chronic follicular conjunctivitis is spread via direct contact with ____
(chlamydia trachomatis)
fomites, fingers, flies
Chronic follicular conjunctivitis is characterized by ____
(chlamydia trachomatis)
follicular hypertrophy
(inflammatory nodules that cover conjunctiva which scratch the cornea and cause blindness of years)
Urethral infection of chlamydia trachomatis affects __% of general population and has a ___ incubation period
5% general population
2-6 week incubation period
chlamydia trachomatis infections _______ of women.
infects ____ of men and women
women: columnar epithelial cells of endocervix, upper genital tract
men and women: urethra, conjunctiva
Initial attachment of chlamydia trachomatis is mediated by ____ followed by ____
MOMP followed by endocytosis of bacteria
LGC biovars can also enter through breaks in skin/mucosa
After chlamydia trachomatis is acquired, primary injury is due to ____
inflammation via IL-8 release (frim infected epithelium and chlamydia LPS)
If immune system cannot control chlamydia trachomatis infection, _____ aggregate in the ___ causing ____
lymphocytes and macrophages aggregate in the submucosa
causing necrosis, fibrosis, scarring — leading to infertility in female repro tract or blindness if persistant in eye
Immunity against chlamydia trachomatis is incomplete. What does that mean?
50% of women still shed bacteria 1 year after infection
____ is the most protective against chlamydia trachomatis.
TH1
Th2 response is associated with chronic infection that have worse complications present
What are the 2 eye diseases that can be caused by chlamydia trachomatis
- trachoma
2. inclusion conjunctivitis
What are the 3 genital infections caused by chlamydia trachomatis
- urethritis/epididymitis
- cervicitis, salpingitis, urethral syndrome
- lymphogranuloma venereum (LGV)
Describe trachoma
chlamydia trachomatis eye infection
chronic conjunctivitis that can lead to scarring of cornea
often causes blindness 15-20 years after infection was contracted
Describe inclusion conjunctivitis
chlamydia trachomatis eye infection
acute infection of newborns 5-12 days after birth or even adults
not associated with blindness
if left untreated, can persist 3-12 months and in few cases will lead to infant pneumonia syndrome which usually clears on its own
Describe urethritis/epididymitis
chlamydia trachomatis infection in men can cause difficulty urinating or can cause urethral discharge
Describe cervicitis/salpingitis/urethral syndrome
chlamydia trachomatis infection in women
unusuallyt asymptomatic vaginal discharge with 5-30% developing pelvic inflammatory disease
Describel ymphogranuloma venereum (LGV)
chlamydia trachomatis infection
distinctively different STD caused only by INVASIVE BIOVARS that get into broken skin and cause transient genital lesions followed by swollen lymph nodes in groin (bubo) and can also cause hemorrhagic ulcerative proctitis
We used to diagnose chlamydia trachomatis infections by ____
now, ___
used to use swab of infected region
now can use nucleic acid amplification test (NAAT)
Treatment for non-LGV chlamydia trachomatis infection:
Treatment for LGV chlamydia trachomatis infection:
non-LGV: azithromycin
LGV: doxycycline
Rickettsiae general info
gram negative, small coccobacilli, aerobic, use host GLUTAMATE
Rickettsiae is ___ intracellular parasite of eukaryotes
obligate
Rickettsiae are __-borne
arthropod
Describe the cell envelope of Rickettsiae
LPS + 2 other large OMP (outer membrane protein)
Rickettsiae undergo ____ of it’s genome, leading to loss of many core metabolic capabilities.
This results in it’s dependency on ____
reductive evolution
dependency on host
Rickettsiae are slow growing and divide via ____ in host cell cytoplasm/nucleus
binary fission
The ____ on rickettsiae attach to many cell types (specifically on the ____)
OMP attach to many cell types, specifically endothelium.
Are then taken into cell via endocytosis
How do rickettsiae escape phagosome?
using phospholipase
Rickettsiae bacteria is found in ____
tick saliva
When a tick with rickettsiae bites a human, this causes ____.
necrotic eschar
What is the main disease associated with Rickettsiae?
rickettsiosis
What are the 2 main kinds of rickettsiosis?
- spotted fever group
2. typhus group
Spotted fever group of rickettsiosis aka ___
rocky mountain spotted fever
Spotted fever group of rickettsiosis is caused bY ___
rickettsia rickettsii
Spotted fever group of rickettsiosis highest incidence between _____, in ages ___, most fatal in children under ___.
April-September
Ages 60-69
Fatal in children under 10
Spotted fever group of rickettsiosis has tropism for ___
endothelium
Spotted fever group of rickettsiosis incubation period ____
6-7 days
Spotted fever group of rickettsiosis most common symptom: _____
Describe the details of this symptom
erythematous macule rash
develops on day 2-3. can become petechial
rash begins on extremities and spread to trunk
rash on palms/soles = diagnostic
Spotted fever group of rickettsiosis is left untreated can cause ____
complications that lead to death
like blood clots, low platelets, encephalitis, VASCULAR COLLAPSE (leading to renal/heart failure)
How do you diagnose spotted fever group of rickettsiosis
hazardous to culture, difficult to diagnose until a week later when antibodies are already created
begin therapy based on clinical signs, symptoms, patient history, followed by SEROLOGICAL DIAGNOSIS to confirm when using indirect fluorescent antibody or skil lesion biopsy
Treatment of spotted fever group of rickettsiosis
doxycycline within first week
there may not be a treatment after that….
The typhus group of rickettsiosis causes 3 different diseases. What are they?
- epidemic typhus fever
- endemic murine typhus
- scrub typhus
Epidemic typhus fever is caused by _____
spread by ____
caused by rickettsia prowazekii
spread by LICE
____ is the only epidemic rickettsial disease
epidemic typhus fever
In what populations is epidemic typhus fever found?
NOT IN US
primarily in homeless populations/refugee camps in Africa, latin america, asia
Some southeastern US flying animals can cause occassional sylvatic case
Describe how epidemic typhus fever infects humans
bacteria circulates in blood, infects lice on the human, kills lice 7-21 days later but presents in their poop 5-10 days after infection
when lice feed, they poop which allows bacteria to re-enter the bloodstream
What are the symptoms of epidemic typhus fever?
incubation period/symptoms begin 1-2 weeks after infection
20-80% of patients get maculopapular rash (starting on trunk and spreading to spreading to extremities)
How do you diagnose epidemic typhus fever?
clinical history used to begin treatment, serology to confirm
What is the treatment for epidemic typhus fever?
doxycycline - must begin immediately
if untreated - fatality rate is 10-60% and increases with age
Endemic murine typhus is caused by ____
Transmitted by ____
caused by rickettsia typhi
transmitted by rat flea in similar way louse-borne typhus is transmitted
Scrub typhus caused by ____
transmitted by ____
caused by orienta tsutsugamushi
transmitted by chiggers as they feed
Scrub typhus initial lesion is ____
necrotic eschar
fever slowly increases over a week maculopappular rash appears on trunk and then extremities (starting on trunk then extremities)
Scrub typhus is treated with ____
doxycycline
Bartonella is ____ intracellular parasite
facultative
Bartonella prefers to infect ____
endothelium
then erythrocytes
Bartonella is an opportunistic pathogen spread by ________
ticks, FLEAS, flies, mosquitoes
Bartonella can cause co-infections with ___
lyme disease
What are the 2 diseases associated with bartonella?
cat scratch disease
trench fever
Cat-scratch disease is caused by ____
Spread by ____
Prevention by ____
Symptoms: ____
bartonella hensealae
spread by cat scratch or bite, or by cat fleas
prevention: controlling fleas
main symptom: swollen lymph nodes
Trench fever is caused by ____
spread by ____
target population ____
bartonella quintana
spread by body lice
affects homeless alcoholic men in france and U.S.
Describe spirochetes morphology
spiral/corkscrew, motile, flexible peptidoglycan cell wall with outer bi-layered membrane
hard to see under routine microscopy
What are the main spirochetes important in medicine?
treponema pallidium
borrelia burgdorferi
Many spirochettes are part of normal ____
flora of oral cavity
What is trench mouth?
named from WWI troops
correlated with severe malnutrition, neglect of basic oral hygiene
spirochetes + anaerobic flora cause necrotizing, ulcerative infection of gums, oral cavity, pharynx
Describe treponema pallidium general info
highly motile spirochete, no LPS, easily killed, hard to study, causes syphilis
Describe the biology of treponema pallidium
minimalistic pathogen (relies on host for basic needs) strict anaerobe , slow growing
Treponema pallidum is acquired by ____
direct sexual contact with someone who has an active primary or secondary lesion (teriary = not contagous), contaminated needles
Congenital syphilis is acquired through ____
(treponema pallidum)
acquired through transplacental transmission from mom to baby
In developed countries, incidence of primary/secondary syphilis and congenital syphilis is ____
on the rise
Treponema pallidium pathogenesis can reach ____
subepithelial tissues through unapparent breaks in skin/mucous membrane where it slowly multiplies without detection
sopread to blood spread
Primary lesion of treponema pallidum causes ___
endarteritis (inflammation of inner lining of artery)
causing necrotic ulceration later
Primary syphilis general info
associated w/ treponema pallidium (spirochetes)
3 wks after exposure, primary lesion forms at contact point, 40% of the time it’s painless, non-itchy
7-10 days later, lymp node enlargement
without treatment, lesion will spontaneously heal 4-6 weeks
Secondary syphilis general info
associated w/ treponema pallidium (spirochetes)
occurs 2-8 weeks after primary infection in 1/3 patients
macolupapular rash appears on palms/soles, sometimes on trunk and extremities
lesions are HIGHLY contageous.
2/3 patients will develop LATENT SYPHILIS, 1/3 spontaneously clears
Latent syphilis general info
associated w/ treponema pallidium (spirochetes)
no clinical symptoms, serological positive tests
occassional relapse can occur
pregnant women can transmit this to the fetus
Secondary syphilis: 2/3 patients develop latent syphilis
other 1/3 of patients develop ____. When would this take place?
teriary syphilis.
associated w/ treponema pallidium (spirochetes)
Occurs 15-20 years later in numerous ways
Tertiary syphilis can occur in what ways?
is this contagious?
1 neurosyphilis (neuro deficits) - common HIV patients
2 ocular syphilis - permanent blindness
3 cardiovascular syphilis - can lead to aneurysms
4 gumma - localized granuloma reaction found all over body
THIS IS NOT CONTAGIOUS
All stages of syphilis are….
diagnosed via ____
treated via ____
diagnosed via serological detection of antibodies
treated with penicillin
T/F Borrelia burgdorferi has no LPS
true
Borrelia burgdorferi is visible with ____ staining
giemsa or wright stains
Why is borrelia burgdorferi reliant on host cell?
lacks genes for many esential nutrients
Describe the genome of borrelia burgdorferi
partitioned genome that contains many icrcular and linear plasmids
borrelia burgdorferi has ___ different subspecies, and multiple classes of ___
18 diff subspecies
multiple classes of OMPs (OspA and OspC, differently expressed depending on whether the bacteria is inside a tick or mammal)
Borrelia burgdorferi primarily live on ___
rodents, TICK LARVAE feed on the mice adn get the bacteria
borrelia burgdorferi is mainly contracted in ___
spring/summer when nymphs are feeding on hosts as part of life cycle
borrelia burgdorferi ID level
less than 20
borrelia burgdorferi has a life cycle that lasts 2 years, includes 3 blood meals. Describe these 3 meals.
- larvae hatch from UNINFECTED EGGS, feed on infected host, acquire bacteria
- infected larvae molt into nymphs, feed on host and infect them with bacteria
- nyphs molt into adults which feed on DEER and mate
(lyme disease only present when they feed on DEER)
NO DEER = NO DISEASE
this is associated with what bacteria
borrelia burgdorferi (spirochetes)
Describe primary lyme disease symptoms
associated w/ borrelia burgdorferi
symptoms begin within 1 month
appear as bull’s eye rash (erythema migrans) at bite site
fever, myalgia, joint pain
Describe secondary lyme disease symptoms
associated w/ borrelia burgdorferi
happens in 50% of patients, develops secondary lesions that resemble the primary one. can develop days to months after primary rash
involves nervous and cardiovascular systems
- cranial nerve palsies - bilateral bell’s
- atrioventricular block leading to heart enlargement
- arthritis
Chronic lyme’s idsease is likely an ____
associated w/ borrelia burgdorferi
likely an autoimmune state
Diagnosis of borrelia burgdorferi diseases ____
based on exposure and clinical findings
can be hard for the 30% who don’t develop this rash
sEROLOGY can be used for later stage detection
Prevention of borrelia burgdorferi diseases via ___
wearing protective clothing to reduce chances of getting tick
promptly remove tick if found (bc they must feed for 48-72 hours)
Treatment of borrelia burgdorferi via ___
doxycycline or b-lactams
