Prescribing Safety Assessment (PSA) Practice Exam

What vitamin deficiency is associated with macrocytic anemia?

1. Vitamin C

2. Vitamin B12

3. Vitamin D

4. Vitamin K

The correct answer is: Vitamin B12

Macrocytic anemia is primarily linked to deficiencies in vitamins that are essential for DNA synthesis, particularly vitamin B12 and folate. Vitamin B12, also known as cobalamin, plays a crucial role in the production of red blood cells. A lack of vitamin B12 leads to megaloblastic anemia, where the body's ability to produce red blood cells is impaired, resulting in larger than normal red blood cells (macrocytes) that are often insufficient in number and function. Deficiency in this vitamin can result from various factors, including dietary insufficiency, malabsorption disorders, or certain medications that affect absorption. The impact of vitamin B12 deficiency on hematopoiesis is significant because vitamin B12 is necessary for proper cell division in the bone marrow. Without adequate B12, the red blood cells not only become enlarged but also do not mature correctly, leading to anemia. While other vitamins, such as vitamin C and vitamin D, play roles in different biological processes, they are not directly associated with macrocytic anemia. Vitamin K is important for blood coagulation but does not influence red blood cell production or size in the same way that vitamin B12 does. Thus, the association of macrocytic anemia with vitamin B12 deficiency