26th Page Flashcards
What is the causative agent of Syphilis?
Treponema pallidum
What were the previous names for Syphilis?
“Great rox” or “Evil Pox”
Why is Syphilis often referred to as “the Great imitator”?
It mimics other diseases or conditions.
Does Syphilis have a natural reservoir in the environment?
No, it requires a living host.
What is the shape and motility of Treponema pallidum?
Spiral shaped (8-24 coils) and motile due to peri-plasmic endoflagella.
What are the modes of transmission (MOT) for Syphilis?
Sexual contact, direct blood transmission, transplacental route.
What is the Columbian theory regarding Syphilis?
Syphilis was transmitted from the New World (America) to the Old World (Europe) by Christopher Columbus and his crew.
What are other Treponema-associated diseases in humans?
T. pallidum subsp. pertenue (Yaws),
T. pallidum subsp. endemicum (Bejel),
T. carateum (Pinto),
T. cuniculi (Rabbit).
What is the Wassermann test?
The first diagnostic blood test based on the principle of complement fixation.
What characterizes Primary Syphilis?
Hard Chancre (painless and firm).
What characterizes Secondary Syphilis?
Condylomata lata
wart-like lesions in moist areas of the body.
Condylomata lata
What is the lab diagnosis for Primary Syphilis?
Dark field microscopy.
What is the lab diagnosis for Secondary Syphilis?
Dark field microscopy.
Serologic test for syphilis.
What occurs during the Latent stage of Syphilis?
Absence of clinical symptoms
Patients are noninfectious, except for pregnant women who can pass the disease to the fetus.
What are Gummas in Tertiary Syphilis?
Localized areas of granulomatous inflammation found on bones, skin, or subcutaneous tissue.
What is key to the identification of Treponema pallidum?
Observation of motility (Corkscrew)
What stain is used for identifying Treponema pallidum?
Nigrosin Black.
Why must specimens be examined quickly in Syphilis diagnosis?
To prevent them from drying out.
What can cause false-negative results in Syphilis testing?
Delay in evaluating the slides, insufficient specimen, or pretreatment with antibiotics.
What is the direct examination method for diagnosing syphilis?
_____________ microscopy or fluorescent antibody testing of sample.
What is the purpose of non-treponemal serological tests?
To detect Reagin; it is a screening test only, not diagnostic.
What are non-treponemal tests based on?
Flocculation reactions - patient Ab complexes with the cardiolipin Ag.
What is Reagin?
An antibody formed against cardiolipin.
What diseases can Reagin be found in?
Found in sera of patients with syphilis as well as other diseases.
What are some examples of non-treponemal tests?
RPR (Rapid Plasma Reagin)
TRUST (Toluidine Red Unheated Serum Test)
USR (Unheated Serum Reagin)
RST (Reagin Screen Test).
What is the purpose of specific treponemal antibody tests?
To detect Ab against T. pallidum; it is a confirmatory test for a positive reagin test.
Both a qualitative and quantitative slide flocculation test for serum and CSF.
VDRL
What does the antigen/reagent for VDRL consist of?
0.03% Cardiolipin
0.9% Cholesterol
0.21% Lecithin.
What is the specimen requirement for VDRL?
50 µL or 0.05 mL serum heated at 56 °C for 30 minutes to inactivate complements.
What is the reinactivation process for serum in VDRL?
Serum is heated at 56°C for 10 minutes if the interval between testing and inactivation is more than 4 hours.
RPR?
A modified VDRL test involving macroscopic examination of flocculation.
What does the antigen/reagent for RPR consist of?
Cardiolipin
cholesterol
lecithin
additional:
EDTA
Thimerosal
choline chloride.
What is the specimen requirement for RPR?
50 µL or 0.05 mL serum (no heat-inactivation).
What is the time and speed of the rotator for VDRL serum?
180 RPM (4 mins) with a diameter of 14mm
What is the time and speed of the rotator for VDRL CSF?
180 RPM (8 mins) with a diameter of 16 mm
What is the time and speed of the rotator for RPR?
100 RPM (8 mins) with diameter of 18 (????) mm
In VDRL flocculation is examined through
microscopically
In VDRL, it uses slides with ceramic rings
TRUE
does it use plastic card in RPR
YES
prevents oxidation of lipid in RPR
EDTA
Preservative in RPR
Thimerosal
Inactivate the complement and stabilize the antigen
Choline chloride
