Syphilis and VDRL Test.pptx

A brief overview of syphilis and an outlook on the frequently requested VDRL test.
An insight into other investigative modalities for the diagnosis of syphilis.

1. VDRL Test Dr. M. Yigah

2. Definition Venereal Disease Research Laboratory (VDRL) test is a non-treponemal serological test that is used to screen for syphilis. Screening tool (not a confirmatory test) Designed by Harris, Rosenberg and Riedel in 1946 Developed in the Venereal Disease Research Lab in the USA Treponemal Pathogenesis and Immunology Branch of PH

3. Overview of Syphilis Syphilis is a venereal disease Can be transmitted from mother to child (congenital syphilis) WHO epidemiological report (2012) Global prevalence (aged 15 – 49) of 18million -- (highest in Africa) Global incidence (aged 15 – 49) -- 1.5 per 1000 (same for both sexes) High risk groups – MSM, RVI patients, sex workers

4. Overview of Syphilis Historical Perspective Columbian theory (1492) vs Pre-Columbian theory First outbreak – 1494/1495 during the siege of Naples by the French (French Disease). Treponema pallidum was discovered in 1905 by F. Schaudinn and E.Hoffmann in 1905. Wasserman Reaction Test was designed in 1906 by Wassermann, Neisser and Bruck Initially being managed with Arsenic compounds until discovery of Penicllin in 1928. The VDRL test was designed in 1946

5. Overview of Syphilis Treponema pallidum – Gram negative Member of spirochaetes Treponema sp – T. carateum (Pinta), T. pertenue (Yaws) Borrelia sp – B. burgdorferi (lime disease) Leptospira sp (leptospirosis) T. pallidum is a Teflon pathogen Stimulates little immune response Human are the only known host Fastidious bacteria – difficult to culture

6. Endemic Syphilis T. Carateum (PINTA) T. Pertenue (YAWS)

7. Clinical Presentation Mode of transmission Sexual contact of all kinds with infectious lesions of the mucous membranes Direct contact of a broken skin with infected mucosal or skin lesions Mother to child transmission during pregnancy Blood transfusion Mean incubation period of 21 days (range: 9–90 days) Clinical features progress through stages Primary stage syphilis Secondary stage syphilis Latent phase Tertiary stage syphilis

8. Primary Stage Syphilis Chancre Solitary painless hard-base sore at the site of inoculation -- Chancre Vagina, penis or anus May be extra-genital Exudate is highly infectious May not be seen by patient Resolves within 3-6 weeks Bacteria spread through the blood and lymphatic systems

9. Secondary Stage Syphilis Maculopapular rash Condylomata lata 2wk to 2 mo after the appearance of Chancre. Development of mucocutaneous rash of varying appearances Usually over the palms and soles Often symmetrical and non-pruritic Usually maculopapular rash (not vesicular) Condylomata lata Lesions are infectious Usually resolves within 3 mo

10. Tertiary Stage Syphilis Occur in 25% of untreated cases Can affect any organ system up to 30 years or more after infection Main manifestations are Neurosyphilis personality changes and other signs of dementia cranial nerve dysfunction and auditory ophthalmic and ocular abnormalities loss of coordination of voluntary movement ( tabes dorsalis) General paresis Gummatous syphilis granulomatous-like lesions of the liver, bone, skin, brain etc. Cardio syphilis Damage to aortic valves leading to aortic regurgitation Non-atherosclerotic coronary artery disease

11. Laboratory Diagnosis Diagnosis of syphilis can be complex Natural progression of the disease Each stage of the disease has its own requirement Availability of some of the labs and their shortcoming Laboratory test for diagnosis Direct detection methods Serological test Non-treponemal serological tests Treponemal serological test

12. Direct detection methods Used to screen and confirm syphilis Important in diagnosing Primary syphilis (Antibodies -- 1-4 wk ) Samples - primary chancres, moist secondary lesions or lymph nodes Darkfield microscopy (commonest) Direct fluorescent antibody test for T.pallidum (DFA-TP) Direct test for T.pallidum in tissue sections Polymerase Chain Reaction (PCR)

13. Dark field Microscopy Oldest and simplest but very reliable Specimen is collected from moist lesions Useful in early stages of primary syphilis or immunocompromised patient Highly operator dependent Low sensitivity – diagnosis cannot be ruled out bacteria is not seen

14. Direct fluorescent antibody test for T.pallidum (DFA-TP) Fluorescein isothiocyanate-labelled anti-T.pallidum antibody Cannot differentiate between endemic and venereal syphilis

15. Other Direct detection methods Direct test for T.pallidum in tissue sections Tissue sections are taken for analysis using Fluorescein isothiocyanate-labelled anti-T.pallidum antibody Immunohistochemistry staining Silver staining techniques Polymerase Chain Reaction (PCR) Using genetic probes to detect T.pallidum DNA or RNA in clinical specimens

16. Serological Tests Non-treponemal serological test Venereal Disease Research Lab Rapid Plasma Reagin ELISA test that uses the VDRL antigen. Treponemal Serological test Treponema pallidum haemagglutination assay (TPHA) Treponema pallidum particle agglutination assay (TPPA) Fluorescent treponemal antibody absorbed (FTA-ABS) tests

17. Treponemal Serological Test Detect specific anti-treponemal antibodies Higher sensitivity and specificity than nontreponemal tests It is a confirmatory test for the 1 st syphilitic infection after a positive vdrl screen Do not differentiate venereal syphilis from endemic syphilis (yaw and pinta ) These test remain positive for life after the first infection in 85% of cases It is not used to monitor treatment or diagnose reinfections.

18. Fluorescent treponemal antibody absorbed (FTA-ABS) tests Uses a slide coated with T.pallidum antigen (Nichol strain) The processed serum is added to the slide to react with the antigen FICT-labelled anti-human immunoglobulin is added to react to the patients antibodies

19. Treponemal Serological Test (TPHA and TPAA) TPHA Detects antibodies that agglutinate RBC sensitized with T. pallidum antigen Sensitivity Primary syphilis – 76% Secondary syphilis – 100% Early latent stage—97 – 100% Late latent stage – 94% TPAA Uses biologically inert coloured gel particle instead of RBC

20. Serological (Non-Treponemal) Tests These tests are common and reliable means of diagnosing syphilis. Antibodies take about 1 to 4 weeks to form Serum is the specimen of choice Plasma can be used some non-treponemal serological tests CSF is used in congenital syphilis and tertiary syphilis (with neuro symptoms) Presumptive diagnosis – positive result from at least one of these types of tests Confirmed diagnosis – Treponemal and non-treponemal test must positive .

21. Serological (Non-Treponemal) Tests VDRL Test and Rapid Plasma Reagin (RPR) They detects the anti-lipid IgM and IgG antibodies (Reagin) produced by the body Hence the term Non-treponemal antibodies Principle of flocculation of in-vitro antibodies – antigen reaction Qualitative and Quantitative tests The VDRL test – is a qualitative slide microscopic-flocculation test Antigen -- alcohol solution of 0.03% cardiolipin, 0.21% lecithin, and 0.9% cholesterol When the antigen combine with antibodies, it forms flocculates that are visible with a microscope. The RPR is a qualitative macroscopic flocculation test The antigen contain other additives to make the reaction visible to the unaided eye

22. VDRL Test and RPR VDRL Test Rapid Plasma Reagin

23. Serological (Non-Treponemal) Tests VDRL Test and Rapid Plasma Reagin (RPR) A positive VDRL test or RPR – Presumptive Syphilis Diagnosis Needs to be confirmed with Treponemal Test or Direct Detection Methods The confirmatory tests helps rule out any false-positives A negative VDRL test or RPR – Does not rule out diagnosis May be falsely negative up to 4 weeks after the appearance of primary lesion (chancre). In primary syphilis, repeated testing at 2 and 4 weeks may be needed to exclude diagnosis when suspect lesions are present A negative test 3 months after onset a suspected primary chancre excludes the diagnosis. May be falsely negative in latent stage of syphilis May be falsely negative because of Prozone reaction

24. Serological (Non-Treponemal) Tests Acute conditions (< 6 mo) Pneumonia Hepatitis Tuberculosis Chicken pox, HIV, Measles Immunization Pregnancy Lyme disease, Leprosy Malaria Lab errors Chronic conditions (>6 mo) Chronic liver disease Malignancy Aging SLE

25. Serological (Non-Treponemal) Tests False Negative Reaction Technical error – unsatisfactory antigen or technique Low antibody titres Presence of inhibitors in the patients serum Reduced ambient temperature Prozone reaction Sensitivities of the VDRL in primary, secondary, latent and late latent are 78%, 100%, 95% and 71% sensitivities of RPR are 86%, 100%, 98% and 73%. The mean specificities of both tests are 98%

26. Serological (Non-Treponemal) Tests Quantitative VDRL or RPR It determine the antibody titres The serum is doubly diluted in saline from 1in 2 to 1:256 or more Samples from each of the dilution well to perform the qualitative vdrl test The highest dilution showing flocculation is considered as reactive titer

27. Serological (Non-Treponemal) Tests Quantitative VDRL or RPR Used to monitor progress of treatment Primary and Secondary Syphilis Monitoring of titres at 3, 6 and 12 mo after start of antibiotic therapy A 4 fold decrease of 2 sequential titres by 3 to 6 mo (e.g. 1/16 to 1/4 or1/32 to 1/8) – effective treatment An increase, unchanged or less than 4 fold decrease in titres -- treatment failure (? Compliance) Early Latent Stage A 4 fold decrease of titres by 1 year Late latent and Tertiary stage Titres should fall by 4 folds over 1 to 2 years Titres may remains reactive at a low level (<1:8) for many years after adequate treatment (50%)

28. Serological (Non-Treponemal) Tests Quantitative VDRL or RPR Can be used to diagnosis reinfections After a successful treatment the titres should be low or negative. Treponemal tests are not useful because the antibodies produced are life-long A rise in serum titres after a successful treatment is suggestive of an infection [Recommendation ---To do the VDRL titres at one particular lab at the start of treatment]

29. Serological (Non-Treponemal) Tests Strengths of VDRL test Widely available Relatively inexpensive Critical for monitoring progress of treatment For diagnosing reinfections Only method for CSF examination of CSF Limitations Low sensitivity in early primary and late latent syphilis False positive results Prozone reaction

30. Special Cases HIV and Syphilis Similar presentation to patients without HIV More chancre and ulcerating lesions High incidence of false negative test with VDRL Biopsy of lesions for direct detection methods Pregnancy and Syphilis VDRL is checked at least once (Ideally repeated in 3 rd trimester) Higher incidence of false positives Thorough history, examination and confirmatory test CSF and VDRL Used to test for tertiary syphilis with CNS involvements Congenital syphilis Treatment failure HIV patient and latent syphilis of unknown duration

31. Treatment of Syphilis Antibiotics therapy Penicillin is the drug of choice to treat syphilis. Benzathine penicillin product should be used, not Benzathine-procaine penicillin. Primary or secondary syphilis – IM Benzathine penicillin G 2.4 million units stat (single dose) Early latent syphilis - Benzathine penicillin G 2.4 million units IM in a single dose Late latent syphilis or latent syphilis of unknown duration - Benzathine penicillin G 7.2 million units total, administered as 3 doses of 2.4 million units IM each at 1-week intervals Pregnancy - Treatment appropriate to the stage of syphilis is recommended Alternatives to penicillin Doxycycline is the best alternative for treating early and late latent syphilis Tetracycline, erythromycin, ceftriaxone and Azithromycin Treat all infected partners and education on prevention of STD

32. Take Home Message VDRL is a non-treponemal serological test used to screen for syphilis Presumptive diagnosis Not sensitive in the early stages of Primary syphilis Direct observation method can be helped cover this limitation Serial testing also helps VDRL titres are the best ways to follow up on treatment, diagnosis treatment, failure or reinfections

33. References Syphilis Treatment & Management – Medscape WHO Guidelines For The Treatment of Treponema pallidum A History of Syphilis and its Laboratory Diagnosis Resolving the Common Clinical Dilemmas of Syphilis Surajit Nayak and Basanti Acharjya -VDRL Test and its Interpretation - 2012