Why Do Clotted Specimens Yield Positive DAT Results with Anti-C3

question 3

Multiple Choice

Why do clotted specimens yield positive DAT results with anti-C3 in the presence of a benign cold autoagglutinin?

• A) Complement is inhibited due to calcium chelation.
• B) Complement can be activated in vivo.
• C) Complement can be activated in vitro.
• D) Complement is activated in the absence of fibrinogen.

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Definitions:

Achromatopsia

Achromatopsia is a rare, non-curable eye condition characterized by total color blindness, visual acuity loss, and light sensitivity due to the absence or malfunction of cone cells in the retina.

Color-blindness

A deficiency in the way someone sees color, making it difficult to distinguish between certain colors.

Dominant

In genetics, a term to describe the ability of an allele for a trait to mask the presence of another allele.

Allele

A variation of a gene, resulting from mutation, that occurs in the same location on a chromosome, among two or more possibilities.