$$\text{Antibody} + \text{Soluble Antigen} \rightarrow \text{Immune Complex}$$

Question 1

Which of the following best describes a primary immunodeficiency?

Accepted Answer

A congenital disorder resulting from inborn errors affecting one or more immune factors.

Question 2

A patient with DiGeorge syndrome is most likely to have which of the following immune defects?

Accepted Answer

Underdeveloped or absent thymus leading to low T cell numbers and defective T cell responses.

Question 3

Which therapy is commonly used to treat primary immunodeficiencies caused by B cell defects?

Accepted Answer

Intravenous or subcutaneous antibody administration.

Question 4

A patient develops immunodeficiency after prolonged use of prednisone. This is an example of:

Accepted Answer

Secondary immunodeficiency.

Question 5

Which infectious agent is most strongly associated with the development of Guillain-Barré syndrome?

Accepted Answer

Campylobacter jejuni.

Question 6

Which of the following is a characteristic feature of systemic lupus erythematosus (SLE)?

Accepted Answer

Autoantibodies against DNA, histones, and ribonucleoproteins.

Question 7

Which hypersensitivity reaction is mediated by T cells and manifests after 12–72 hours?

Accepted Answer

Type IV hypersensitivity.

Question 8

A patient presents with a pruritic red rash after contact with poison ivy. Which mechanism is responsible?

Accepted Answer

T cell–mediated delayed hypersensitivity reaction.

Question 9

Which equation best represents the formation of immune complexes in Type III hypersensitivity?

Accepted Answer

$$	ext{Antibody} + 	ext{Soluble Antigen} ightarrow 	ext{Immune Complex}$$

Question 10

Which blood type is considered the universal recipient for transfusions?

Accepted Answer

AB+

Question 11

A newborn develops severe anemia due to maternal IgG antibodies crossing the placenta. What is the most likely cause?

Accepted Answer

Hemolytic disease of the newborn due to Rh incompatibility (Type II hypersensitivity).

Question 12

Which of the following is NOT a typical symptom of autoimmune disorders?

Accepted Answer

Sudden onset of high blood pressure.

Question 13

Which of the following is a mechanism underlying Type II hypersensitivity reactions?

Accepted Answer

IgG or IgM binding to nonsoluble antigens on cell surfaces, leading to complement activation.

Question 14

A patient with multiple sclerosis is experiencing delayed nerve impulse transmission and pain. Which cells are being attacked?

Accepted Answer

Myelin-producing cells in the nervous system.

Question 15

Which equation best represents the complement activation in Type II hypersensitivity?

Accepted Answer

$$	ext{Antibody} + 	ext{Cell Surface Antigen} ightarrow 	ext{Complement Activation} ightarrow 	ext{Cell Lysis}$$

Question 16

Which of the following is most likely to cause a secondary immunodeficiency?

Accepted Answer

Chronic disease such as diabetes or hepatitis.

Question 17

Which hypersensitivity reaction is most likely responsible for anaphylactic shock?

Accepted Answer

Type I hypersensitivity.

Question 18

Which of the following is a real-world example of a Type III hypersensitivity reaction?

Accepted Answer

Serum sickness following administration of antitoxins.

Question 19

Which equation best represents the delayed response in Type IV hypersensitivity?

Accepted Answer

$$	ext{T Cell} + 	ext{Antigen} ightarrow 	ext{Cytokine Release} ightarrow 	ext{Inflammation}$$

Question 20

Which of the following is a possible outcome of bone marrow transplantation related to immune system disorders?

Accepted Answer

Graft-versus-host disease (GVHD), where donor white blood cells attack host tissues.

Immune System Disorders: Immunodeficiencies, Autoimmunity, and Hypersensitivity Reactions

Study Guide - Practice Questions