Question
Test shown in the photograph below is a type of?
A. Indirect hemagglutination test.
B. Slide flocculation test.
C. Gel precipitation test.
D. None of the above.
Show Answer
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Correct Answer » B Explanation |
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Ans:B. Slide Flocculation test.
The test shown in the picture above is VDRL.
VDRL
- Venereal Disease Research Laboratory (VDRL) Test is a slide flocculation testemployed in the diagnosis of syphilis.
- Since the antigen used in this test is cardiolipin, which is a lipoidal extracted from beef heart, it is not a specific test.
- This test is also classified as non-specific or non-treponemal or standard test.
- The antibodies reacting with cardiolipin antibodies have been traditionally (but incorrectly) termed “regain”.
VDRLprinciple:
- When the heat inactivated (to destroy complement) serum of patient is reacted with freshly prepared non-treponemal antigen, flocculation reaction (antigen and antibody complex are suspended) occurs.
- The flocculation can be observed by using microscope.
- Reactive VDRL test serum can be quantitated to obtain the titre of “reagin antibodies” by using serial double dilution method.