RPR TEST KIT
Catalogue Number Product description
RPR/010 RPR Test Kit 100 T
RPR/012 RPR Test Kit 500 T
The PLASMATEC RPR test is a complete test system for the detection of syphilis, which utilises plasma, unheated or heated serum. The test antigen is a modified form of VDRL Antigen containing microparticulate carbon which aids the macroscopic reading of results. A reactive result is indicated by agglutination which is readily visible without the aid of a microscope. Weak- reactive results can be easily and clearly distinguished from non-reactive patterns which display a macroscopically smooth and even appearance

KIT PRESENTATION
1. Antigen (2ml) : 100 test
  Antigen (10ml) : 500 test
  This reagent is ready for use and is supplied in 2ml/10ml capped vials. Time must be allowed for the antigen to reach room temperature prior to testing and should be WELL SHAKEN to ensure homogeneity. All RPR test antigen should stored in the refrigerator at 2-8°C with the cap fully tightened, when not in use. Do not freeze antigen.
2. Positive/negative controls 1ml
  Controls are supplied so the validity of the test can be checked periodically. The controls are supplied ready for use.
3. Syringe and needle
(1x2ml syringe and 1 dispensing needle)
  These components are designed for dispensing the RPR test antigen. For use, attach the needle to the end of the syringe and draw the WELL SHAKEN antigen into the syringe. Expel a drop or two of antigen to eliminate the possibility of an inadequate amount of antigen being added to the sample due to the presence of air in the needle. It is extremely important to maintain syringe and needle in a vertical position when dispensing the antigen. At the end of each day's testing the needle should be removed, rinsed with distilled water and air dried. The dispensing needle should not be wiped. Doing so may remove the silicon coating thereby allowing some antigen to adhere to the needle, which may result in insufficient antigen being delivered.
4. Test Cards
  These cards are for use with the PLASMATEC RPR antigen suspension and are specially prepared, plastic coated cards. The circles of the test cards should never be touched with the fingers, as this may invalidate test results. Each test area should only be used once and then the card should be discarded or filed for future reference.
5. Pipette stirrers (100) : 100 test
  Pipette stirrers (500) : 500 test
  The droppers are used to transfer serum or plasma to the test card surface and one drop is equivalent to approximately 50ml. In qualitative tests, a new dropper must be used for each test specimen. When transferring the sample from the collecting tube, the specimen must not be drawn up into the teat as this may cause false results.
  ADDITIONAL REQUIREMENTS
1. Automatic rotating table.
2. Pipettes capable of delivering 50 µl.
  SAMPLE PREPARATION
  Plasma, unheated or heated serum may be used. Test material should be free of bacterial contamination and non-lysed.
  QUALITATIVE METHOD
1. Hold the teat between the thumb and forefinger. Squeeze the teat whilst inserting the dropper onto the specimen. Then release finger pressure to withdraw the sample taking care not to transfer any cellular elements.
2. Hold the dropper over a test card circle and squeeze the teat to allow one drop (50 µl) to fall onto the card. It is important to maintain the dropper in a vertical position whilst dispensing the sample to be tested.
3. Using the broad end of the stirrer, spread the sample of the entire area of the test circle.
4. Attach the dispensing needle to the syringe. Withdraw sufficient antigen (WELL SHAKEN) for the number of tests performed. Maintaining the syringe in a vertical position, allow one drop to fall on each test sample. Do not restir.



RESULTS
At the end of 8 minutes rotation, inspect the test card macroscopically, in a good light.
Reactives display characteristic agglutination ranging from slight (Weak-reactive) to intense (Reactive). Very weak reactive results are characterised by small agglutinates around the periphery of the test area. Negatives do not exhibit this reaction and display a macroscopically smooth and even appearance.

QUANTITATIVE METHOD
1. Dispense one drop of 0.85% saline on circles 1 to 5, of the test card using disposable pipette. Do not spread the saline.
2.  Using an accurate volumetric pipette dispense 50 µl of test sample onto circle number 1.
3. Using the dropper prepare two-fold dilutions by drawing the mixture up and down the pipette 5 or 6 times. Avoid the formation of bubbles. Transfer 50ul from circle numbers 1 to 5 which now represent the following dilutions:
CIRCLE 1 2 3 4 5
DILUTION 1:2 1:4 1:8 1:16 1:32
4. Using a mixer spread the diluted sample across the entire surface of each circle starting at the highest dilution (circle number 5). Proceed to circles number 4, 3, 2 and 1 in a similar fashion.
5. Using the syringe and needle withdraw sufficient antigen (WELL SHAKEN) for the number of tests being performed. Maintaining the syringe in a vertical position allow one drop to fall onto each test circle. Do not restir. Rotate the RPR test card manually or using an automatic rotator for 8 minutes at 100 revolutions/minutes.
 
RESULTS
At the end of 8 minutes of rotation, inspect the test card macroscopically, in good light.
Read the test and note the last circle in the dilution series that has a positive example:
If the highest dilution tested (1:32) is Reactive, proceed with the dilutions series as follows:-
5.1 Prepare a 1:16 dilution of the test sample by adding 0.1 ml of serum or plasma to 1.5ml of 0.85% saline.(1:16 dilution). Mix well.
5.2 Dispense one drop of 0.85% saline onto circles 6, 7, 8, 9 and 10.
5.3 Dispense one drop of the 1:16 dilution (prepared in 5.1) onto circle number 6. Then proceed as in step 2. The circles 6, 7, 8, 9 and 10 now represent the following dilutions:-
CIRCLE 6 7 8 9 10
DILUTION 1:32 1:64 1:128 1:256 1:512
Complete the test by following the steps number 3 and 4.

NOTES
In common with all reagin tests the RPR test may give a small proportion of false positive results.
Such reactions can be caused by diseases such as infectious mononucleosis, leprosy, lupus erythematosus, vaccinia and virus pneumonia.
Reactive RPR test specimens should be subject to further serological studies (i.e TPHA, FTA, and ABS) since, as with any serological testing procedure, the diagnosis of syphilis should not be made on a single reactive result.