Which medication is an immunomodulator?

Correct Answer: A

Rationale: The correct answer is A: Leflunomide, as it is an immunomodulator that acts by inhibiting pyrimidine synthesis, thereby suppressing the immune response in autoimmune diseases like rheumatoid arthritis. Methotrexate (B) is an immunosuppressant that inhibits DNA synthesis. Hydroxychloroquine (C) is an antimalarial drug with immunomodulatory effects but is not primarily used for this purpose. Adalimumab (D) is a biologic agent that targets tumor necrosis factor-alpha and is classified as a TNF inhibitor, not an immunomodulator.

Correct Answer: B

Rationale: The correct answer is B because correctly identifying the client prior to a blood transfusion helps prevent a type II hypersensitivity reaction by ensuring compatibility between the donor and recipient blood types. This prevents the recipient's immune system from attacking the transfused blood, which can lead to a reaction. Administering steroids for a positive TB test (choice A) is unrelated to preventing type II hypersensitivity reactions. Keeping the client free of the offending agent (choice C) is more relevant to preventing type IV hypersensitivity reactions. Providing a latex-free environment for the client (choice D) is important for preventing latex allergies, a type I hypersensitivity reaction, not type II.

Correct Answer: C

Rationale: The correct answer is C: Bone marrow infiltration. When the bone marrow is infiltrated by tumors or other abnormal cells, it impairs the production and release of erythropoietin, leading to decreased erythropoietin response and subsequent anemia. Hypothyroidism (choice A) does not directly affect erythropoietin levels. Myelofibrosis (choice B) is associated with increased erythropoietin levels due to ineffective erythropoiesis. Thalassemia (choice D) is a genetic disorder affecting hemoglobin production, but it does not directly impact erythropoietin response.

Correct Answer: A

Rationale: The correct answer is A: Thymus. The thymus is considered a primary lymphoid tissue because it is where T cells mature and differentiate. It plays a crucial role in the development of the immune system. The other choices, B: Spleen, C: Lymph node, and D: Liver, are considered secondary lymphoid tissues where immune responses take place but not where lymphocytes mature.

Correct Answer: C

Rationale: The correct answer is C because it accurately states that pemphigus is an autoimmune disease that causes blistering of the skin. This demonstrates an understanding of the underlying cause of the condition. Option A is incorrect as pemphigus presents with blistering, not tiny red vesicles. Option B is incorrect as pemphigus is not caused by a virus. Option D is incorrect as the description provided does not match the characteristic presentation of pemphigus.