STANDARD OPERATING PROCEDURES FOR VDRL TESTING

1. SPECIMEN:

1. Plasma or Serum

2. EQUIPMENTS & REAGENTS

1. Equipments:
   1. NycoCard Reader
   2. CRP Kit (includes reagents).

2. Reagents:

1. RF Latex Direct Reagent
2. Positive Control Serum
3. Negative Control Serum

3. PROCEDURE:

1. Mix 5 µL whole blood with Dilution Liquid. Mix well.
2. Apply 50 µL diluted sample to the Test Device
3. Apply one drop Conjugate
4. Apply one drop Washing Solution
5. Read the test result with the NycoCard READER II
6. Procedure: Patients’ serum is inactivated by heating at 56o C for 30 minutes in a water bath to remove non-specific inhibitors (such as complement). The test can be performed both qualitatively and quantitatively. Those tests that are reactive by qualitative test are subjected to quantitative test to determine the antibody titres. Qualitative test: 0.05 ml of inactivated serum is taken into one well. 1/60th ml (or 1 drop from 18 gauge needle) of the cardiolipin antigen is then added with the help of a syringe (unbeveled) to the well and rotated at 180 rpm for 4 minutes. Every test must be accompanied with known reactive and non-reactive controls. The slide is then viewed under low power objective of a microscope for flocculation. The reactive and non-reactive controls are looked first to verify the quality of the antigen. Depending on the size the results are graded as weakly reactive (W) or reactive (R). Reactive samples are then subjected to quantitative test. Qualitative test: this is performed to determine the antibody titres. The serum is doubly diluted in saline from 1in 2 to 1:256 or more. 0.05 ml of each dilution is taken in the well and 1/60 ml of antigen is added to each dilution and rotated in a rotator. The results are then checked under the microscope. The highest dilution showing flocculation is considered as reactive titre. Sometimes, due to very high level of antibodies in the serum (prozone phenomenon) the qualitative test may be non-reactive. If the clinica
7. Examine under a bright light source for the presence of agglutination
   1. Agglutination (clumping of the latex particles) indicates a positive result. A weakly reactive serum produces a very fine granulation or partial clumping.
   2. The absence of agglutination indicates a negative result.
8. Prepare lab report of the observations.