ASCP Immunology and Serology

Question 1

The VDRL and RPR tests are nontreponemal screening tests for which disease?

Accepted Answer

Syphilis

Answer

VDRL and RPR detect cardiolipin-lecithin antibodies (reagin) produced in response to Treponema pallidum infection.

Question 2

Which immunoglobulin class is the first produced in a primary immune response?

Accepted Answer

IgM

Answer

IgM is the first antibody class produced during a primary immune response due to its rapid synthesis from B-cell activation.

Question 3

A positive ANA (antinuclear antibody) test is most associated with which autoimmune disease?

Accepted Answer

Systemic lupus erythematosus (SLE)

Answer

ANA is positive in >95% of SLE patients; anti-dsDNA and anti-Sm are specific confirmatory tests for SLE.

Question 4

ELISA (enzyme-linked immunosorbent assay) is used as the initial test for HIV diagnosis because:

Accepted Answer

It has high sensitivity to minimize false negatives

Answer

ELISA has high sensitivity for HIV antibody detection, minimizing missed infections; reactive results are confirmed by Western blot or HIV-1/2 differentiation assay.

Question 5

Rheumatoid factor (RF) is an antibody directed against:

Accepted Answer

The Fc portion of IgG

Answer

Rheumatoid factor is typically an IgM antibody that binds the Fc region of IgG; it is elevated in rheumatoid arthritis and other inflammatory conditions.

ASCP Practice Test

ASCP Practice Test

ASCP Immunology and Serology