Lab Diagnosis of Syphilis

Lab diagnosis of syphilis:

Principle: Labrotaroy diagnosis of secondary syphilis of direct demonstration of treponema by M/E and serological tests.

Steps:Specimen

a)      Tissue fluids from the lesion particularly from the primary chance or secondary rash.

b)      Serum for serology.

c)      CSF(Cerebro spinal fluid).

[A]Microscopically examination:Dark ground Illumination(DGI) using oil immersion lense.

Findings:Bright red colour and cork screw movement of treponema palladium can be seen.

[B]Immunofluroscence test:Tissue fluid is smeared on a slide,air dried fixed and stained by fluroscen labeled antitreponema serum.

[C]Serological test:

(A)Non Treponemal antibody test/Non specific antibody test:Reagin test:Detection of regain

a)      VDRL(Veneral disease reasearch lab test)

b)      RPR(Rapid plasma reagen test)

c)      CFT(Compliment fixation test)

(B)Treponemal antibody test/Specific antibody test:

a)      TPHA(Treponama pallidum haemagglutination test):The principle of test in RBC (absorbed treponemast patients serium)

b)      TPA(Treponama pallidum antibody test)

c)      FTA-ABS(Fluorosent treponemal antibody absorption test):Here patients serum should be absorbed by sonicated Reitters stain. Killed T pallidum+Absorbed patient serum+Lable antihuman gamma globulin.

d)     TPI(Treponema pallidum immobilization test):This tests requires the highly infective strain.Treponema pallidum of the Nicoles strain.

e)      Compliment fixation test:RP(CFT):Reitters protein compliment fixation test.This test is more specific than the STS(Standered test for syphilis)

(C)ELISA(Enzyme linked immuno sorbant assay):If newly introduced techniques that is introduced this test is very simply to perform and is equivalent to the FTA(ABC)

[D]Examination test:

a)      Routine examination.

b)      Langes test.

c)      WR,VDRL,FTA-ABS.