IVD

Bacterial Antigens Kit (Wright, Rose Bengal Test)

SUMMARY OF WRIGHT TEST

Principles of Rose Bengal Test

The Rose Bengal test (RBT) is a rapid slide-type agglutination assay performed with a stainedB. abortussuspension at pH 3.6–3.7 and plain serum. Because of its simplicity, it is often used as a screening test in human brucellosis and would be optimal for small laboratories with limited means. [SZ1] 

Packaging Contents

Rose Bengal Antigen: 6 vials of Rose Bengal Antigen (each vial contains 10 ml Rose Bengal Antigen).

1 vial containing polyvalent serum.

1 vial containing negative serum.

Storage and Stability

Store at 2-8°C. Do not freeze.

The antigen and Controls are stable until the expiry date stated on the label.

Procedure

Bring the test reagents and samples to room temperature.

Resuspend the antigen vial gently. Pipette the solution several times to obtain a homogenous mixture.

Place 1 drop (30 µL) of the serum onto one of the circles on the card.

Dispense 1 drop of positive control serum and 1 drop of negative control serum into two additional circles.

Add 1 drop of Rose Bengal Antigen to each circle next to the sample to be tested.

Mix the contents of each circle with a disposable stirrer while spreading over the entire area enclosed by the ring. Use separate stirrers for each mixture.

Rotate the slide slowly by hand for 4 minutes.

Observe immediately under a suitable light source for any degree of agglutination.

 Interpretation

Nonreactive: Smooth suspension with no visible agglutination, as shown by negative control.

Reactive: Any degree of agglutination visible macroscopically. All reactive specimens should be further tested to clarify the situation.

Quality Control

Positive and negative controls should be run daily following the steps outlined in the procedure in order to check the optimal reactivity of the antigen. The positive control should produce clear agglutination. If the expected result is not obtained, do not use the kit.

Precautions

          •        Before use, allow reagents to reach room temperature (18-30°C).

          •        Do not use expired reagents.

          •        Use glassware washed and rinsed with distilled water, or preferably use disposable material.

          •        Use a new tip for each sample

          •        Bacterial contamination of controls and specimens as well as freezing and thawing of the antigen may lead to false positive results.

          •        The reagents in this kit contain chemical material. Do not allow to contact with skin or mucous membranes.