CEA Nursing Practice Exam

A 43-year-old male with macrocytic anemia should be evaluated for which lab level to determine the etiology?

1. Vitamin B12.

2. Lead level.

3. Ferritin.

4. TIBC.

The correct answer is: Vitamin B12.

Macrocytic anemia is often associated with deficiencies in certain vitamins, primarily vitamin B12 and folate. In a case involving a 43-year-old male presenting with macrocytic anemia, assessing vitamin B12 levels is critical to identify the underlying cause of the anemia. A deficiency in vitamin B12 can result from various factors such as dietary insufficiency, malabsorption syndromes, or intrinsic factor deficiency, which leads to pernicious anemia. Measuring vitamin B12 levels provides valuable insight into whether insufficient amounts are contributing to the anemia. A low level would support the diagnosis of vitamin B12 deficiency, whereas a normal level would prompt further investigation into other potential causes, such as folate deficiency. While other tests like lead level, ferritin, and TIBC can be useful for evaluating different types of anemia, they are not the primary focus when determining the etiology of macrocytic anemia. Lead levels relate more to microcytic anemia, ferritin assesses iron stores often for microcytic anemia, and TIBC (total iron-binding capacity) evaluates iron metabolism but is not specifically informative for macrocytic anemia. Therefore, checking vitamin B12 is the most relevant and critical lab value in this situation.