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Medical Term:

plasmacrit test


Definition: a serologic screening method used as an aid in the diagnosis of syphilis; after only a few drops of heparinized blood (obtained from a pricked finger) are collected in a special capillary tube, the capillary tube is centrifuged in order to collect plasma, which is then mixed with a 0.01-mL drop of antigen (cardiolipin previously treated with choline chloride as an antiinhibitor, to avoid falsely negative results that may occur with nonheated plasma or serum). After mechanically agitating the antigen-plasma mixture for 4 minutes, the presence or absence of flocculation is observed. A positive result should not be regarded as conclusively diagnostic, but a negative result excludes the likelihood of syphilis.

© Copyright 2017 Wolters Kluwer. All Rights Reserved. Review Date: Sep 19, 2016.