67. A 53-year-old patient is being seen by an advanced practice registered nurse (APRN) for complaints of fatigue and headache. The patient reports a decrease in energy and the inability to complete a typical morning walk but denies feeling dizzy with changes in positions or any symptoms of bleeding. The APRN notes that the patient appears pale and vital signs are within normal limits. The APRN suspects anemia and orders a CBC with differential. The result of the mean corpuscular volume (MCV) is >100. The APRN orders further testing to differentiate the cause of the macrocytic anemia. Which set of anemias should the APRN suspect?
Answer: D
Folate or B12 deficiency
The APRN should suspect folate or B12 deficiency as the cause of the macrocytic anemia indicated by the mean corpuscular volume (MCV) result of >100. These deficiencies are commonly associated with macrocytic anemia and can lead to the symptoms observed in the patient.
A) Aplastic or hemolytic
Aplastic anemia is characterized by a decrease in red blood cell production due to bone marrow failure, while hemolytic anemia involves the premature destruction of red blood cells. Neither of these conditions typically presents with macrocytic anemia as indicated by an increased MCV, making this option incorrect.
B) Thalassemia or iron deficiency
Thalassemia is a microcytic anemia, and iron deficiency anemia generally presents with microcytic red blood cells as well. Since the patient's MCV is greater than 100, indicating macrocytic anemia, this option does not fit the clinical scenario.
C) Sideroblastic or hemoglobin E
Sideroblastic anemia is usually associated with microcytosis and impaired hemoglobin synthesis, while hemoglobin E is a variant that typically does not cause macrocytic anemia. Therefore, this option is not consistent with the patient's macrocytic anemia.
D) Folate or B12 deficiency
Folate and B12 deficiencies are the primary causes of macrocytic anemia, leading to larger than normal red blood cells. Given the patient's symptoms and the MCV result, this option aligns perfectly with the suspected diagnosis.
Conclusion
The correct answer is D, as folate or B12 deficiency directly relates to the macrocytic anemia indicated by an MCV greater than 100. Other options, such as aplastic or hemolytic anemia, thalassemia or iron deficiency, and sideroblastic or hemoglobin E, do not correspond with the macrocytic findings and are therefore incorrect in this context.