1.4 Hematology: Macrocytic and Normochromic Anemias

D. RBC = 2.5 × 1012/L; WBC = 2,500/μL (2.5 × 109/L); PLT = 50,000/μL (50 × 109/L) D Patients with pernicious anemia demonstrate a pancytopenia with low WBC, PLT, and RBC counts. Because this is a megaloblastic process and a DNA maturation defect, all cell lines are affected. In the bone marrow, this results in abnormally large precursor cells, maturation asynchrony, hyperplasia of all cell lines, and a low M:E ratio.

A 50-year-old patient is suffering from pernicious anemia. Which of the following laboratory data are most likely for this patient? A. RBC = 2.5 × 1012/L; WBC =12,500/μL (12.5 × 109/L); PLT = 250,000/μL (250 × 109/L) B. RBC = 4.5 × 1012/L; WBC = 6,500/μL (6.5 × 109/L); PLT = 150,000/μL (150 × 109/L) C. RBC = 3.0 × 1012/L; WBC = 5,000/μL (5.0 × 109/L); PLT = 750,000/μL (750 × 109/L) D. RBC = 2.5 × 1012/L; WBC = 2,500/μL (2.5 × 109/L); PLT = 50,000/μL (50 × 109/L)

B. Increased MCV B The patient will have an increased MCV. One of the causes of a macrocytic anemia that is not megaloblastic is an increased reticulocyte count, here noted as increased polychromasia. Reticulocytes are polychromatic macrocytes; therefore, the MCV is slightly increased.

A patient has 80 nucleated red blood cells per 100 leukocytes. In addition to increased polychromasia on the peripheral smear, what other finding may be present on the CBC? A. Increased platelets B. Increased MCV C. Increased Hct D. Increased red blood cell count

B. An improvement in hematological abnormalities B Administration of folic acid to a patient with vitamin B12 deficiency will improve the hematological abnormalities; however, the neurological problems will continue. This helps to confirm the correct diagnosis of vitamin B12 deficiency.

A patient with a vitamin B12 anemia is given a high dosage of folate. Which of the following is expected as a result of this treatment? A. An improvement in neurological problems B. An improvement in hematological abnormalities C. No expected improvement D. Toxicity of the liver and kidneys

B. Elevated reticulocyte count B Megaloblastic anemias are associated with an ineffective erythropoiesis and therefore a decrease in the reticulocyte count.

All of the following are characteristics of megaloblastic anemia except: A. Pancytopenia B. Elevated reticulocyte count C. Hypersegmented neutrophils D. Macrocytic erythrocyte indices

C. Ovalocytic C Macrocytes in true megaloblastic conditions are oval macrocytes as opposed to the round macrocytes that are usually seen in alcoholism and obstructive liver disease.

The macrocytes typically seen in megaloblastic processes are: A. Crescent-shaped B. Teardrop-shaped C. Ovalocytic D. Pencil-shaped

D. Pernicious anemia D Pernicious anemia is caused by a lack of intrinsic factor, which prevents vitamin B12 absorption.

Which anemia is characterized by a lack of intrinsic factor that prevents B12 absorption? A. Tropical sprue B. Transcobalamin deficiency C. Blind loop syndrome D. Pernicious anemia

D. Macrocytic, normochromic D Megaloblastic macrocytic anemia is normochromic because there is no defect in the Hgb synthesis. These anemias comprise a group of asynchronized anemias characterized by defective nuclear maturation due to defective deoxyribonucleic acid (DNA) synthesis. This abnormality accounts for the megaloblastic features in the bone marrow and the macrocytosis in the peripheral blood.

Which morphological classification is characteristic of megaloblastic anemia? A. Normocytic, normochromic B. Microcytic, normochromic C. Macrocytic, hypochromic D. Macrocytic, normochromic

C. MCV 125 fL, MCH 36 pg, MCHC 34% C The red cell indices in a patient with megaloblastic anemia are macrocytic and normochromic. The macrocytosis is prominent, with an MCV ranging from 100 to 130 fL.

Which of the following are most characteristic of the red cell indices associated with megaloblastic anemias? A. MCV 99 fl, MCH 28 pg, MCHC 31% B. MCV 62 fL, MCH 27 pg, MCHC 30% C. MCV 125 fL, MCH 36 pg, MCHC 34% D. MCV 78 fL, MCH 23 pg, MCHC 30%

D. Megaloblastic anemia D Ineffective erythropoiesis is caused by destruction of erythroid precursor cells prior to their release from the bone marrow. Pernicious anemia results from defective DNA synthesis; it is suggested that the asynchronous development of red cells renders them more liable to intramedullary destruction.

Which of the following disorders is associated with ineffective erythropoiesis? A. G6PD deficiency B. Liver disease C. Hgb C disease D. Megaloblastic anemia

B. Macrocytes B Patients with obstructive liver disease may have red blood cells that have an increased tendency toward the deposition of lipid on the surface of the red cell. Consequently, the red cells are larger or more macrocytic than normal red cells.

Which of the following may be seen in the peripheral blood smear of a patient with obstructive liver disease? A. Schistocytes B. Macrocytes C. Howell-Jolly D. Microcytes