Hypersensitivity Flashcards
- Which of the following is a general characteristic of hypersensitivity reactions?
a. The immune responsiveness is depressed.
b. Antibodies are involved in all reactions.
c. An exaggerated immune response to an antigen occurs.
d. The antigen triggering the reaction is a harmful one.
c. An exaggerated immune response to an antigen occurs.
- Which of the following is associated with an increase in IgE production?
a. Transfusion reaction
b. Activation of Th2 cells
c. Reaction to poison ivy
d. HDN
b. Activation of Th2 cells
- Which of the following would cause a positive DAT test?
a. Presence of IgG on RBCs
b. Presence of C3b or C3d on RBCs
c.A transfusion reaction caused by preformed antibody
d. Any of the above
d. Any of the above
- All of the following are associated with type I hypersensitivity except
a. release of preformed mediators from mast cells.
b. activation of complement.
c. cell-bound antibody bridged by antigen.
d. an inherited tendency to respond to allergens.
b. activation of complement.
- Which of the following is associated with anaphylaxis?
a. Buildup of IgE on mast cells
b. Activation of complement
c. Increase in cytotoxic T cells
d. Large amount of circulating IgG
a. Buildup of IgE on mast cells
- To determine if a patient is allergic to rye grass, the best test to perform is the
a. total IgE test.
b. skin prick test.
c. DAT.
d. complement fixation.
b. skin prick test.
- Which condition would result in HDN?
a. Buildup of IgE on mother’s cells
b. Sensitization of cytotoxic T cells
c. Exposure to antigen found on both mother and baby RBCs
d. Prior exposure to foreign RBC antigen
d. Prior exposure to foreign RBC antigen
- What is the immune mechanism involved in type III hypersensitivity reactions?
a. Cellular antigens are involved
b. Deposition of immune complexes occurs in antibody excess
c. Only heterologous antigens are involved
d. Tissue damage results from exocytosis
b. Deposition of immune complexes occurs in anti-body excess
- What is the immune phenomenon associated with the Arthus reaction?
a. Tissue destruction by cytotoxic T cells
b. Removal of antibody-coated RBCs
c. Deposition of immune complexes in blood vessels
d. Release of histamine from mast cells
c. Deposition of immune complexes in blood vessels
- Which of the following conclusions can be drawn about a patient whose total IgE level was determined to be 150 IU/mL?
a. The patient definitely has allergic tendencies.
b. The patient may be subject to anaphylactic shock.
c. Antigen-specific testing should be done.
d. The patient will never have an allergic reaction.
c. Antigen-specific testing should be done.
- Which of the following explains the difference between type II and type III hypersensitivity reactions?
a. Type II involves cellular antigens.
b. Type III involves IgE.
c. IgG is involved only in type III reactions.
d. Type II reactions involve no antibody.
a. Type II involves cellular antigens.
- Two days after administration of the PPD test, a female health-care worker developed an area of redness and induration 12 mm in size at the injection site. This result means that she has
a. an active case of tuberculosis.
b. been exposed to M tuberculosis.
c. developed protective immunity against tuberculosis.
d. a result in the normal range for her risk group.
b. been exposed to M tuberculosis.
- A young woman developed red, itchy papules on her wrist 2 days after wearing a new bracelet. This reaction was caused by
a. IgE-sensitized mast cells in the skin.
b. antigen-antibody complexes in the skin.
c. damage to the skin cells by antibodies and
complement.
d. an inflammatory response induced by cytokines released from Th1 cells.
d. an inflammatory response induced by cytokines released from Th1 cells.
- Reactions to latex are caused by
a. type I hypersensitivity
b. type IV hypersensitivity
c. skin irritation.
d. all of the above.
d. all of the above.
- To determine a cold agglutinin titer
a. patient serum should be separated from whole blood at 4°C and tested at 4°C.
b. patient serum should be separated from whole blood at 4°C and tested at 37°C.
c. patient serum should be separated from whole blood at 37°C and tested at 4°C.
d. patient serum should be separated from whole blood at 37°C and tested at 37°C.
c. patient serum should be separated from whole blood at 37°C and tested at 4°C.
