L8 MHD: Spirochetes Flashcards
(51 cards)
Treponema Pallidum:
- Light microscopy or Darkfield
- Vector/reservoir
- Transmission
- Disease
- use Darkfield
- NO vector/reservoir
- Intimate sexual contact
- Disease = SYPHILLIS
Leptospira Interrogans
- Light microscopy or Darkfield
- Vector/reservoir
- Transmission
- Disease
- Use dark field
- Rats, mice, wild rodents, dogs, swine, cattle
- Contact or ingest urine-contaminated water (surfer’s disease)
- Leptospirosis!
Borrelia Recurrentis
- Light microscopy or Darkfield
- Vector/reservoir
- Transmission
- Disease
- Light microscopy
- V= louse + tick
Reservoir = rodents - Transmitted by ticks or lice
- RELAPSING fever
Borrelia Burgdorferi
- Light microscopy or Darkfield
- Vector/reservoir
- Transmission
- Disease
- Yes - Light microscopy
- Vector = tick
Reservoir = Mouse, deer
- Transmission via (ixodes deer) TICKS
- Lyme borreliosis
Treponema Pallidum:
- Seen on ____ or ____
- Outer membrane: Does NOT contain ____
- What is the internal flagellum called?
- Immunofluorescence or darkfield
- No LPS
- Internal flagellum is called AXIAL FIBRIL
The following are characteristics of _____:
- Helical morphology
- Flexible peptidoglycan cell wall
- Axial fibrils that wind around cell wall
- covered by outer membrane
SPIROCHETES
Treponema & leptospira are THIN and seen only by dark field microscopy
BLT
- burrelia (can be seen with light microscopy)
- leptospira
- treponema
Culture of T. Pallidum:
- Cultured on _____
- Differentiated by clinical association only, why?
- What type of respiration?
- rabbit epithelial cells
- Generation time – 30 hours - Because structural & metabolic differences between treponemes have to been found.
- differentiated by clinical association only - MICROAEROPHILLIC!
- Outer membrane protein antigens cloned but pathogenicity not well characterized
Syphillis Transmission:
- Major contact? With what?
- How does congenital infection arise?
- Lesions of tertiary syphillis are contagious (T/F)
- No sexual spread if greater than ___ years after acquiring infection
- Intimate sexual contact with infective PRIMARY or SECONDARY lesion
- genitals, anus, lip - Dissemination through PLACENTA
- FALSE: lesions of primary and secondary syphilis are contagious
- 4 years!
How have US rates of syphillis changed?
Linked to what 3 things?
Marked increase among what population?
Decreased in ____
INCREASED since 2005
- Drug use
- Truck Routes
- core groups
Increase in GAY MEN
Decreased rates among FEMALES
(most common in white non hispanic males)
PATHOGENESIS:
- Syphillis passes through ____ or ____
- Multiplies locally and disseminates to____ and other organs
- Symptoms or signs when number of organisms reaches critical mass
Primary _____ days after inoculation - What is the pathologic lesion of syphillis?
- What stages are self-limiting?
- Intact mucosa or Abraded skin
- lymph nodes
- 10-90
- OBLITERATIVE ENDARTERITIS
- Hypersensitivity and autoimmunity may play late role - Primary and secondary stages are self-limiting
(each followed by periods of latency)
- immunity to reinfection after treatment of early syphillis is NOT enough to prevent reinfection
- immunity after later stages is more substantial
Primary Syphillis:
- What appears at the site of inoculation? This also results in regional _____
- Painless papule is called a ____
- Describe the ulcer
- T/F: systemic manifestations appear in primary stage.
- Heals ____
- ULCERATIVE LESION
- regional adenopathy - CHANCRE
- PAINLESS papule that ulcerates
(10-90 days after initial infection) - Ulcer has smooth , heaped up margins and dry crusted base
(liquid from base is dark field positive)
+ FIRM LOCAL ADENOPATHY
- FALSE: no fever/chills
- Heals spontaneously
Secondary Syphillis:
- What type of illness?
- What type of rash? Is the whole body covered?
- In Moist areas, papillose coalesce to form _____
- What other sites are affected?
- Fever & generalized ______
- SYSTEMIC flu-like illness
- may develop 2-10 weeks after primary lesion heals - PAPULOSQUAMOUS rash
- entire body including pass and soles
ALSO mucocutaneous rash with generalized lymphadenopathy & organ (liver, kidney, CNS involvement)
- CONDYLOMA LATA
- Hepatitis, aseptic meningitis, periostitis, nephritis (IMMUNE COMPLEX type)
- LYMPHADENOPATHY
What is a papulosquamous rash? Which stage of syphillis is this characteristic of?
- Red, elevated lesion that is easily felt, rough on the surface with a sandpaper texture
- HYPERKERATOTIC - SECONDARY SYPHILLIS
What is the difference between adenopathy between primary and secondary syphillis?
- Primary = REGIONAL lymphadenopathy
- genital area (inguinal etc.) - Secondary = GENERALIZED (neck/axillary)
One third of untreated syphillis cases resolve spontaneously.
The reminder progress to what?
What is positive in this stage?
Clinically what is seen?
- LATENT SYPHILLIS
- presence of POSITIVE treponema serologic test in
- the absence of clinical manifestations
(1/3 of untreated cases become LATE syphillis)
Late Syphillis presents in what 3 major organ systems?
- Neurosyphillis
- TABES Dorsalis
- (demyelination of nerves) - Cardiovascular
- proximal aorta & branches –> causing aneurisms due to AORTITIS
- can lead to ascending aortic aneurism
“tree barking of aorta”
(syphillis destroys the vast vasorum –> smaller vessels that supply the aorta) - Late Benign GUMMATOUS
- granulomatous lesions in skin, mucocutaneous areas, bones
- soft growth with firm necrotic center
Describe the 4 kinds of neurosyphilis.
- Asymptomatic
- Meningovascular
- Paresis
- Tabes dorsalis (what sensory deficits present?)
- Asymptomatic
- CSF infected w/o symptoms or signs (only seen as infection in CSF) - Meningovascular
- chronic meningitis which can affect major arteries to brain & cranial nerves
(stroke is possible/ without HTN) - Paresis
- CORTICAL DEGENERATION w/ mental changes - Tabes dorsalis
- demyelination of posterior colums & dorsal roots
**LOSS OF PAIN, temp, proprioception
+ ATAXIA
Congenital Syphillis:
- Infection occurs ____
- T/F: symptoms present at birth
- Prevent with what?
- What is recommended during pregnancy?
- IN UTERO infection (typically 1st trimester)
- FALSE no symptoms at birth
- multi system disease later
a) rhinitis
b) rash
c) bone & cartilage involvement
d) liver, spleen, lymph nodes , CNS - Penicillin during pregnancy (de-sensitize person if allergic, since tetracyclines are contraindicated in pregnancy)
- ROUTINE SCREENING recommended
What are the pupils that arise due to tertiary Syphillis?
What congenital defects are associated with syphillis?
Argyle - Robinson pupils
- can accommodate but not react to light!
= stay dilated when light is shined
(prostitute pupils)
FIRST AID:
- Saber shins
- Saddle shaped nose
- Hutchinson’s teeth (notched)
- Mulberry molars
- CN VIII deafness!!
- RHAGADES (linear scars at angle of mouth)
Microscopy for syphillis includes what 3 tests:
- ___ for primary & secondary lesions
- Immunofluorescence with monoclonal antibodies ______
- ___ which is not used clinically
- DARKFIELD
- Direct Fluorescent Antibody Test
- PCR
Reaginic Antibodies for Syphillis serology are IgG & IgM directed against _____
(not T. Pallidum!)
- CARDIOLIPIN
- a lecithin cholesterol mixture present on mitochondrial membrane
- extracted from beef heart
- reason for forming these antibodies is unknown
- antibodies not directed against T. Pallidum
- What is VDRL?
- What bodily fluid is used?
- is it specific?
RPR?
What is common with these tests?
- VDRL: Veneral Disease Research Lab
a) - done on CSF to screen for T. Pallidum
- detects non-specific antibody that reacts with Cardiolipin
b) QUANTITATIVE, SENSITIVE, but NOT specific
- Rapid Plasma Reagin
- directed against SERUM - FALSE POSITIVE is common
V - viral infection
D - drugs
R - rheumatic fever
L - leprosy/lupus
The following are examples of what?
- FTA - Abs
- TPPA
- EIA & CIA
Which has high false positive rate when sued to screen low prevalence pop? (but is used widely)
Which includes adsorbed antigens onto gelatin particle or RBC?
Which test is NOT quantitative?
Which is used to confirm a positive RPR?
SPECIFIC antibody tests for Treponema
- FTA - Abs
-Absorbed with non-T. pallidum treponeme (dead T. palidum)
Antigen is killed Reiter strain T. pallidum
Either reactive or NON reactive (not quantitative)
- TPPA
- Treponemal antigens adsorbed onto gelatin particle or RBC
MHA-TP–Microhemagglutination Treponema pallidum - EIA & CIA
- Chemiluminescence immunoassay
Cheap, automated, now in wide use for screening
- USED to confirm a POSITIVE RPR!!!!
High false positive rate when used to screen low prevalence population
If RPR is positive, but FTA is negative - strong indication that patient DOESN’T HAVE SYPHILLIS
What are some conditions that cause false positives in Serologic Treponema tests:
- Troponemal (2)
- Non treponemal (2)
- Troponemal:
- febrile illness
- pregnancy - Treponemal
- chronic infections
- autoimmune disease** (TEST)
V
D
R
L
V - viral infection
D - drugs
R - rheumatic fever
L - Lupus & leprosy
(AUTOIMMUNE DISORDERS CAUSE FALSE POSITIVE = TEST!!!)