Syphilis Serology (Exam 3)

Syphilis can be spread ______ or can be ______.

sexually, congenital

What are the 4 stages of untreated syphilis?

- Primary

- Secondary

- Latent

- Tertiary

Primary syphilis can be recognized by the presence of a ______.

chancre

Secondary syphilis is characterized by generalized lymphadenopathy, fever, and ______.

rash (hands and feet)

Latent syphilis usually has no ______.

S/Sx

Latent syphilis is noninfectious except ______.

congenitally

Tertiary syphilis can cause ...

- Gummatous syphilis

- CVD

- Neurosyphilis

Tertiary syphilis occurs ______ years post-infection.

10-30

What are the most common/effective treatments of syphilis?

- Penicillin

- Tetracycline or erythromycin

Direct detection via dark field microscopy examines samples taken from the patient's ______.

lesion

Inspection uses a microscopy with a ______ condenser.

dark-field

A positive dark field microscopy direct test indicates the presence of ______ on the black background

motile spirochetes

Direct dark field microscopy may be positive before ______ tests.

serological

Direct detection via fluorescent Ab uses fluorescent-conjugated ______ Ab.

anti-Treponema pallidum

This type of test detects T. pallidum in ______ from the lesion site.

fixed smears

Fluorescent Ab direct detection has better ______ and reduced ______ than dark field microscopy.

sensitivity/specificity, infection risk

Treponemal serological tests detect _______ against T. pallidum or specific ______ associated with it.

Abs, antigens

Treponemal serological tests are usually positive before ______ tests.

non-treponemal

Serological tests are close to 100% reactive if the patient is in ______ or ______ phase.

secondary, latent

What tests are serological?

- TP-PA

- FTA-ABS

- EIA/CLIA

Fluorescent Treponemal Antibody Absorption (FTA-ABS) tests are ______ (direct/indirect).

indirect

FTA-ABS combines ______ with ______.

heat-inactivated patient serum, nonpathogenic treponemes

These two are then ______.

incubated

What is added to the mixture after incubation?

Fluorescent-conjugated secondary Ab

The ______ is then read.

fluorescence (0-4+)

FTA-ABS is very sensitive and specific except for ______ cases.

congenital

Particle Agglutination Tests include ______.

T. pallidum particle agglutination (TP-PA)

TP-PA is very sensitive in detecting what stages of syphilis?

secondary, tertiary, latent

TP-PA tests incubate patient serum in microtiter plates with ______, coated with ______.

gel particles, T. pallidum antigen

A positive (agglutinated) TP-PA results in gel particles ______ in the well, creating a cloudy appearance.

"dissolving"

A negative TP-PA shows particles on the ______.

bottom of the well

Immunoassays are used for ______ and ______ syphilis.

screening (IgG/IgM), congenital (IgM)

What are the types of immunoassays used for syphilis detection?

- Non-competitive ELISA

- Competitive ELISA

- Chemiluminescent immunoassays (CLIA)

Immunoassays are very ______ when it comes to detection of syphilis.

sensitive/specific

Non-treponemal serological tests detect patient IgM and IgG against ______.

cardiolipin

Non-treponemal serological tests are used for ______ and to monitor ______.

screening, therapy

What are the two types of non-treponemal serological tests?

RPR and VDRL

RPR and VDRL are ______ rections.

flocculation

Non-treponemal titers ______ with effective therapy.

decrease

Non-treponemal titers ______ with recent infection, reinfection, or relapse.

increase

Treponemal tests for Abs will always stay _______ once infected with syphilis once.

high

Non-treponemal Ab tests (RDR, VDRL) will _______ after initial syphilis exposure and cessation.

decrease

Non-treponemal tests (RPR, VDRL) will be positive ______ weeks after appearance of ______.

1-4, chancres

In Rapid Plasma Reagin (RPR), the antigen is ______.

cardiolipin as well

In an RPR, very fine particles will show ______ when Ab is present.

clumping

______ is added to RPR to enhance visibility.

Charcoal

RPR is used to monitor patient _______ to therapy after diagnosis.

reaction

RPR is more sensitive than VDRL in the ______ syphilis stage.

primary

RPR Results

The antigen in VDRL is ______.

cardiolipin too

VDRL is performed on ______ and heat-inactivated ______.

CSF, serum (inactivates complement)

VDRL is used more for potential ______.

neurosyphilis

VDRL Results

A ______ can occur with non-treponemal tests, indicating a large amount of Ab in the secondary syphilis stage.

prozone

When a prozone occurs, you should ______ the serum and retest it.

dilute

Biological false positives can occur with additional _______.

viral infections

Biological false positives can also occur due to ______.

chronic disease

Biological false negatives can occur due to ...

- Prozone

- Testing too early

- Latent stage

- Immunodeficient patient

In the lab, false positives/negatives can occur due to ...

- Dried serum on card before antigen is added

- Rotated too long (common!!)

- Not humidified during rotation

- Hot reagents or room

What components are important in daily quality control when in comes to syphilis diagnosis?

- Controlled room temperature

- Rotator speed

- Antigen needle drop size

- Reactive, non-reactive, minimally-reactive controls

What tests are usually done first when it comes to syphilis detection?

EIA/CIA or TP-PA

TP-PA can also be done ______.

last/third

What test is usually done second?

RPR or VDRL

RPR is ______ for positive results.

confirmatory

TP-PA can be done on samples with ______ results.

discrepant

Congenital syphilis is done via ______ followed by ______ or ______.

IgM EIA, Western Blot or PCR

This is because the infant ______ must be detected.

antibodies

VDRL and ELISA only routinely use ______ samples.

CSF

These two are very specific and diagnostic if positive, but lack ______.

sensitivity