Medical Technologist Test Immunology and Serology 2

Question 1

Which hepatitis B serological marker is the FIRST to appear in serum during acute infection?

Accepted Answer

HBsAg

Answer

HBsAg (hepatitis B surface antigen) is the earliest detectable marker in serum, appearing during the incubation period before clinical symptoms.

Question 2

The RPR (Rapid Plasma Reagin) test for syphilis uses which antigen?

Accepted Answer

Cardiolipin-lecithin-cholesterol

Answer

The RPR is a nontreponemal test using a cardiolipin-lecithin-cholesterol antigen to detect reagin antibodies produced during syphilis infection.

Question 3

The prozone phenomenon in serology results in a false-negative reaction due to:

Accepted Answer

Antibody excess preventing lattice formation

Answer

Prozone occurs when antibody greatly exceeds antigen, saturating all antigen binding sites and preventing the cross-linking necessary for a visible reaction.

Question 4

Which test is used as a CONFIRMATORY assay for HIV infection following a reactive screening result?

Accepted Answer

Western blot

Answer

Western blot identifies antibodies against specific HIV proteins (e.g., gp120, gp41, p24) separated by molecular weight and serves as the confirmatory test.

Question 5

C-reactive protein (CRP) is produced primarily by which organ during the acute phase response?

Accepted Answer

Liver

Answer

CRP is an acute phase protein synthesized by hepatocytes in the liver in response to IL-6 released during inflammation or infection.

Medical Technologist Test Practice Test

Medical Technologist Test Practice Test

Medical Technologist Test Immunology and Serology 2