What is the principle of the VDRL test?
The basis of the VDRL test is that body produces antibody when infected, and in this test the antibody is detected by subjecting the serum to an antigen, which is composed of colorless alcoholic solution of beef cardiolipin, cholesterol, and lecithin.
What is the principle of RPR test?
The principle of the RPR test is a flocculation reaction between the RPR antigen and the reagin. The reaction can be seen macroscopically on the test slide as clumping of the carbon particles.
What is the reagent used in VDRL test?
The antibody detected is called “Reagin”. REAGENTS CENOGENICS’ VDRL Antigen is a colorless, alcoholic solution contain- ing 0.03% cardiolipin, 0.9% cholesterol, and sufficient purified lecithin to produce standard reactivity.
Which antigen is used for VDRL test?
The Venereal Disease Research Laboratory (VDRL) test is a microflocculation test for syphilis that uses an antigen containing cardiolipin, lecithin, and cholesterol.
What is the difference between VDRL and RPR testing?
The rapid plasma reagin (RPR) test uses the same antigen as VDRL, but the antigen is bound to a carbon particle to allow visualization of the reaction without a microscope. VDRL or RPR titers are monitored to document response to therapy. RPR titers are frequently higher than VDRL titers.
What is VDRL test non reactive?
A negative (nonreactive) VDRL is compatible with a person not having syphilis, but in the early stages of the disease, the VDRL often gives false negative results.
What is the difference between RPR and VDRL?
What is reagin and cardiolipin?
Non-specific serological tests for syphilis The rapid plasma reagin (RPR) test, which has now largely superseded the earlier Venereal Disease Research Laboratory (VDRL) test, is a non-specific serological test for syphilis that uses cardiolipin as antigen.
How is VDRL antigen prepared?
Add 4.1 ml of VDRL BUFFERED SALINE from a 5 ml pipet. Cap the bottle and shake it from bottom to top and back approximately 30 times in 10 seconds. The VDRL ANTIGEN SUSPENSION is ready for use and is usable for 8 hours. Mix the VDRL ANTIGEN SUSPENSION by gently swirling it each time it is used.
Why RPR is preferred over VDRL?
The fact that the CSF-RPR is significantly more specific than the CSF-VDRL means that it is more likely to be negative than the CSF-VDRL in a patient without neurosyphilis.
What is difference between Vdrl and RPR?
Why is VDRL test positive?
A positive test result means you may have syphilis. If the test is positive, the next step is to confirm the results with an FTA-ABS test, which is a more specific syphilis test. The VDRL test’s ability to detect syphilis depends on the stage of the disease.
What is reagin in syphilis?
A rapid plasma reagin (RPR) test is a blood test used to screen you for syphilis. It works by detecting the nonspecific antibodies that your body produces while fighting the infection. Syphilis is a sexually transmitted infection (STI) caused by the spirochete bacterium Treponema pallidum.
How reagin is formed during syphilis?
Reagin is not specific to T pallidum infection, but is generated as a response to spirochaete-induced damage to cellular membranes, and is a useful indicator of disease activity. In contrast, treponemal tests detect antibody to T. pallidum and are available in a variety of formats.
What type of antibody is Reagin?
reagin, also called homocytotropic antibody, or prausnitz-küstner antibody, type of antibody found in the serum and skin of allergically hypersensitive persons and in smaller amounts in the serum of normally sensitive persons. Most reaginic antibodies are the immunoglobulin E (IgE) fraction in the blood.
What is VDRL slide?
The VDRL test is used to screen for syphilis (it has high sensitivity), whereas other, more specific tests are used to diagnose the disease. Venereal Disease Research Laboratory test. VDRL slide for performing the blood test for syphilis. Purpose. blood test for syphilis.
What is the protocol for Gram staining?
Gram Staining Procedure/Protocol: Flood air-dried, heat-fixed smear of cells for 1 minute with crystal violet staining reagent. Please note that the quality of the smear (too heavy or too light cell concentration) will affect the Gram Stain results. Wash slide in a gentle and indirect stream of tap water for 2 seconds.
What are the reagents used in Gram staining?
Reagents Used in Gram Staining Crystal Violet, the primary stain Iodine, the mordant A decolorizer made of acetone and alcohol (95%) Safranin, the counterstain
What is the difference between Gram positive and Gram negative staining?
After decolorization, the gram-positive cell remains purple in color, whereas the gram-negative cell loses the purple color and is only revealed when the counterstain, the positively charged dye safranin, is added. Fix material on a slide with methanol or heat. If the slide is heat fixed, allow it to cool to the touch before applying the stain.
What types of bacteria can be detected by Gram staining?
Nearly all clinically important bacteria can be detected/visualized using Gram staining method the only exceptions being those organisms; That exists almost exclusively within host cells i.e. Intracellular bacteria (e.g., Chlamydia) Those that lack a cell wall (e.g., Mycoplasma)