digeorge syndrome is a primary immune deficiency caused by

ATI RN

ATI Pathophysiology Test Bank

1. DiGeorge syndrome is a primary immune deficiency caused by:

A. Failure of B cells to mature
B. Congenital lack of thymic tissue
C. Failure of formed elements of blood to develop
D. Selective IgG deficiency

Correct answer: B

Rationale: DiGeorge syndrome is caused by a congenital lack of thymic tissue, which plays a crucial role in T cell development and maturation, leading to immune deficiency. Choice A is incorrect because DiGeorge syndrome primarily affects T cells, not B cells. Choice C is incorrect as it is too broad and not specific to the thymus. Choice D is incorrect as selective IgG deficiency is a different condition unrelated to DiGeorge syndrome.

2. Which of the following disorders is more likely associated with blood in stool?

A. Gastroesophageal reflux
B. Crohn's disease
C. Irritable bowel syndrome
D. Colon cancer

Correct answer: D

Rationale: Colon cancer is more likely associated with blood in stool due to the presence of bleeding from the tumor in the colon. Gastroesophageal reflux (Choice A) typically presents with heartburn and regurgitation but not blood in stool. Crohn's disease (Choice B) can cause gastrointestinal symptoms, but bloody stools are more commonly associated with ulcerative colitis. Irritable bowel syndrome (Choice C) is characterized by abdominal pain, bloating, and changes in bowel habits, but it does not typically cause blood in stool. Therefore, the correct answer is D, Colon cancer.

3. A nurse is teaching a patient about the use of raloxifene (Evista) for the prevention of osteoporosis. What is the primary therapeutic action of this medication?

A. It decreases the absorption of calcium from the intestines.
B. It decreases bone resorption and increases bone density.
C. It increases the excretion of calcium through the kidneys.
D. It stimulates the formation of new bone.

Correct answer: B

Rationale: The correct answer is B. Raloxifene, a selective estrogen receptor modulator (SERM), works by decreasing bone resorption and increasing bone density. This action helps in preventing osteoporosis by maintaining bone strength. Choice A is incorrect as raloxifene does not affect the absorption of calcium from the intestines. Choice C is incorrect as raloxifene does not increase the excretion of calcium through the kidneys. Choice D is incorrect as raloxifene does not directly stimulate the formation of new bone; instead, it primarily works by reducing bone loss.

4. Which of the following is an example of a Type 1 hypersensitivity reaction?

A. Anaphylaxis
B. Indigestion
C. Beta cell destruction
D. ABO transfusion reaction

Correct answer: A

Rationale: Anaphylaxis is a classic example of a Type 1 hypersensitivity reaction. In Type 1 hypersensitivity, allergens trigger an immediate immune response mediated by IgE antibodies, leading to the release of histamine and other mediators. This reaction can result in symptoms ranging from mild itching and hives to severe conditions like anaphylaxis, which is a life-threatening emergency. The other options, such as indigestion (choice B), beta cell destruction (choice C), and ABO transfusion reaction (choice D), are not classified as Type 1 hypersensitivity reactions. Indigestion is typically related to gastrointestinal disturbances, beta cell destruction is associated with autoimmune conditions like type 1 diabetes, and ABO transfusion reaction involves antibodies targeting incompatible blood groups, which is a different immune mechanism compared to Type 1 hypersensitivity.

5. A patient with a history of breast cancer is prescribed tamoxifen (Nolvadex). What critical information should the nurse include in the patient education?

A. Tamoxifen may increase the risk of venous thromboembolism, so patients should be educated about the signs and symptoms of blood clots.
B. Tamoxifen may cause weight gain, so patients should monitor their diet.
C. Tamoxifen may decrease the risk of osteoporosis, so patients should ensure adequate calcium intake.
D. Tamoxifen may cause hot flashes and other menopausal symptoms.

Correct answer: A

Rationale: Tamoxifen increases the risk of venous thromboembolism, so patients should be educated about the signs and symptoms of blood clots and the importance of seeking immediate medical attention if they occur.