A nurse is assessing a patient with suspected folate-deficiency anemia. Which assessment finding would be most characteristic of this condition?
A 45-year-old female patient presents to the clinic with complaints of fatigue and weakness that have been progressively worsening over the past 3 months.
1Microcytic, hypochromic red blood cells
2Decreased white blood cell count with normal platelet count
3Macrocytic, normochromic red blood cells✓ 정답
4Increased reticulocyte count with normal hemoglobin
해설
Folate-deficiency anemia is characterized by macrocytic, normochromic RBCs due to impaired DNA synthesis. Other options describe findings more typical of other anemias or conditions.
Clinical Judgment
This question assesses your ability to distinguish the characteristic findings of different causes of anemia. The key is the pathophysiological understanding that folate deficiency impairs DNA synthesis, disrupting the maturation of red blood cell precursors in the bone marrow. The most characteristic finding on a peripheral blood smear is the observation of megaloblastic red blood cells. The other options are findings seen in anemias from other causes, such as iron deficiency, sickle cell disease, and hereditary spherocytosis.
Memory Tip: Both folate deficiency and vitamin B12 deficiency cause Megaloblastic anemia. "Mega" means large, so the cells appear large (Macro). In contrast, iron deficiency makes cells appear small (Micro).
KR vs US: In Korea, the focus for the main causes of folate deficiency tends to be more on alcoholism, malabsorption, and medications (like methotrexate) rather than nutritional deficiency alone. The US NCLEX emphasizes a comprehensive assessment of various risk factors, including nutritional status, pregnancy, and alcohol intake.
임상 시나리오
Clinical Practice Guide
When evaluating a patient with suspected folate deficiency, a complete blood count (CBC with differential), serum folate, and vitamin B12 levels should be checked. Supplementing with folate without first ruling out vitamin B12 deficiency is dangerous because it can mask neurological damage. Treatment is oral folate supplementation, with injections considered if there is malabsorption.
Caution
In SATA (Select All That Apply) questions, be careful of the trap that includes neurological symptoms (paresthesia, gait disturbance) as "characteristics of folate deficiency." These are primarily features of vitamin B12 deficiency. Also, the reticulocyte count is normal or decreased; if it is increased, hemolysis or bleeding should be suspected.
핵심 개념
Folate-deficiency anemia — Megaloblastic anemia caused by a deficiency of vitamin B9 (folic acid). The main cause is impaired DNA synthesis.
Macrocytic, Normochromic — Red blood cells are larger than normal (Macrocytic), but hemoglobin concentration is normal (Normochromic). This is a characteristic finding of folate or vitamin B12 deficiency anemia.
Megaloblastic anemia — Anemia in which large, immature red blood cell precursors (megaloblasts) are produced in the bone marrow due to defective DNA synthesis. The main causes are folate or vitamin B12 deficiency.
Ineffective erythropoiesis — Ineffective hematopoiesis. A condition where red blood cell production in the bone marrow is increased, but many precursor cells are destroyed within the bone marrow and are not effectively released into the peripheral blood. It appears in megaloblastic anemia.
Reticulocyte count — Reticulocyte count. An indicator for evaluating the bone marrow's ability to produce red blood cells. An increase suggests increased red blood cell production (hemolysis, after hemorrhage), while a normal or decreased level suggests production failure (nutritional deficiency, bone marrow hypofunction).