A 20-month-old otherwise healthy male presents late for his 18-month well child check. During his first year of life, he took iron-fortified formula and had a point-of-care hemoglobin (Hgb) of 12 g/dL at his 1-year well child check. His mother reports that he is a picky eater but loves milk and has recently become obsessive about chewing the corners of his cardboard books. Physical examination is normal except for a flow murmur. Which combination of laboratory test results listed below would most likely characterize this patient?

Correct Answer: A

Rationale: The correct answer is A because it reflects iron deficiency anemia in a 20-month-old child who is a picky eater and has pica behavior. The low hemoglobin level of 8.7 g/dL indicates anemia. The MCV of 60 fL suggests microcytic anemia, typical of iron deficiency. The serum ferritin level of 2 ng/mL confirms low iron stores. Choice B is incorrect as the hemoglobin level is normal, MCV is higher, and serum ferritin is not indicative of iron deficiency anemia. Choice C is incorrect as the hemoglobin level is higher, and the MCV is not consistent with iron deficiency anemia. Choice D is incorrect as the hemoglobin level is higher, MCV is too high for iron deficiency anemia, and the serum ferritin level does not support iron deficiency.

Correct Answer: C

Rationale: The correct answer is C: Check the pressure dressing frequently for signs of excessive or active bleeding. This is the priority because post bone marrow aspiration and biopsy, there is a risk of bleeding due to the procedure. By checking the dressing, the nurse can assess for any signs of excessive bleeding or hematoma formation, which are crucial to prevent complications. A: Teaching the client to avoid activity is important but not the priority immediately post-procedure. B: Administering NSAIDs may not be appropriate as they can increase the risk of bleeding. D: Reporting the lab results is important but not the priority over ensuring immediate post-procedure safety.

Correct Answer: b

Rationale: Correct Answer: B - Decreased red blood cell count Rationale: 1. Anemia is defined by a decrease in red blood cells, causing decreased oxygen-carrying capacity. 2. A decreased red blood cell count is a key indicator of anemia. 3. Other choices are incorrect: A. Increased hematocrit is not expected in anemia, as it indicates a higher concentration of red blood cells. C. Decreased serum iron may be seen in iron-deficiency anemia but is not a universal finding in all types of anemia. D. Decreased hemoglobin is a common finding in anemia but is not as specific as a decreased red blood cell count.

Correct Answer: C

Rationale: Rationale: A low reticulocyte production index indicates decreased bone marrow response to anemia. Aplastic anemia is characterized by bone marrow failure leading to pancytopenia, causing anemia. Thalassemia results in microcytic anemia, not macrocytic. Vitamin B12 deficiency causes macrocytic anemia due to impaired DNA synthesis. Sideroblastic anemia leads to microcytic anemia due to defective heme synthesis. Therefore, the most likely cause of anemia in this patient with a low reticulocyte production index and normal mean cell volume is aplastic anemia.

Correct Answer: D

Rationale: The correct answer is D: Vitamin K deficiency. Prolonged prothrombin time and activated partial thromboplastin time indicate impaired blood clotting, which is a characteristic of Vitamin K deficiency. Vitamin K is essential for the synthesis of clotting factors II, VII, IX, and X. Hemophilia A (Choice A) is a genetic disorder resulting in a deficiency of clotting factor VIII, leading to prolonged activated partial thromboplastin time only. Thrombocytopenia (Choice B) is a condition characterized by low platelet count, which can lead to bleeding but does not affect clotting factors. Von Willebrand disease (Choice C) is a genetic disorder affecting von Willebrand factor and platelet function, not clotting factors.