Serological and Molecular Detection if Spirochete Disease

Long, slender, helically coiled bacteria containing axial filaments, it is gram-negative with corkscrew motility

Spirochetes

Venereal disease that is commonly transmitted sexually, caused by Treponema pallidum subsp. pallidum

Syphilis

Treponema pallidum subsp. pertenue - ____________

Treponema pallidum subsp. endemicum - __________

Treponema pallidum subsp. carateum - ___________

Yaws

Bejel

Pinta

Four stages of Syphilis

Primary

Secondary

Latent

Tertiaty

Initial lesion that appears on the genitourinary area and heals spontaneously. It may heal completely within 4-6 weeks without treatment.

Diagnosis is only based on direct detection of the organism

Primary Stage

Primary stage appearance is

Hard Chancre / Hunterian Chancre

Systemic dissemination of the organism, it may overlap with the primary stage but usually occurs 1-2 months after the primary chancre disappears. Patients are highly infectious at this stage

Secondary Stage

Found in Secondary stage that has wart-ike lesions around the anogenital area

Condyloma lata

Stage where the syphilis may go into a subclinical and non-infectious state, it may last for less tahn a year or up to ten years

Latent Stage

Three major manifestations of Tertiary Syphilis (3)

Gummas

Cardiovascular complications

Neurosyphilis

Localized areas of granulomatous inflammation

Gummas

Most common complication associated with the tertiary stage, it resembles acute meningitis and degeneration of the lower spinal cord with demention

Neurosyphilis

Mother to child transmission of syphilis (transpplacental)

Congenital Syphilis

Presence of rash, jaundice, hepatosplenomegaly, bone malformations

Early stage congenital syphilis

Hutchinson triad of Late stage congenital syphilis

Keratitis

Eight nerve deafness

Hutchinson teeth

Identification based on their corkscrew morphology and flexing motility, a negative result will not exclude a diagnosis of syphilis

Direct Detection

Uses a darkfield condenser to keep all incidental light out of the field except by the light captured by the treponemes

Darkfield Microscopy

First treponemal test to be discovered in 1906

Wasserman Test

Principle of Wasserman Test

Complement Fixation

Designed to detect the presence of antibody that forms against cardiolipin

Non-Treponemal Test

Found in the sera of patients with syphilis and other disease states

Reagin

Reagent complex of Non-Treponemal test is composed of

Cardiolipin

Lecithin

Cholesterol

Flocculation test where serum specimens must be heated at 56C for 30 minutes

Venereal Disease Research Laboratory Test

VDRL

______% Cardiolipin

______% Lecithin

______% Cholesterol

0.03%

0.21%

0.9%

VDRL

_____mL of heated serum is added onto a ceramic ring of a glass slide

One drop of VDRL reagent is added using a ___________ syringe

0.05mL

Hamilton Syringe

VDRL

Three Control Sera

________ - no clumps

________ - small clumps

________ - Medium to Large clumps

Sera with reactive or weakly reactive results are diluted serially (two-fold)

____ → ___

Nonreactive, Weakly Reactive, Reactive

1:2 → 1:32

Modified test of VDRL that uses macroscopic charcoal agglutination test.

Rapid Plasma Reagin Test

RPR reagent consists of CLC + (4)

Charcoal

EDTA

Thimerosal

Choline Chloride

RPR

____ML of serum is added into a __mm in diameter ring of a disposable plastic card

Reagent is added from a ___G calibrated needle

Card is rotated at ____Rpm for ___minutes under humid conditions

0.05mL onto a 18mm ring

20G calibrated needle

100rpm for 8 minutes

Tests that are directed at the detection of Treponemal antigens or antibodies against the organism itself.

It is usually positive before nontreponemal tests. Once a patient is reactive in treponemal tests, they remain reactive for life

Treponemal Tests

Recommended as a confirmatory procedure for syphilis,

FTA-ABS Test (Fluorescent Treponemal Antibody Absorption Test)

FTA-ABS

_________________ - non-pathogenic treponeme that removes antibodies that cross-react with treponemes other than T. pallidum

Apply the serum-sorbent complex to a test slide fixed with ____________ stain

Incubate at ___C for ___ minutes and apply a ____________ conjugate, then reincubate and wash

Reiter Strain

Nichols Stain

37C for 30 minutes, apply fluorescein 2 Ab conjugate

Uses colored gelatin particles coated with treponemal antigens to detect the presence of antibodies in patient sera, more sensitive in detecting primary syphilis

Treponema pallidum Particle Agglutination Test