Complete Blood Count & Bone Marrow Examination

Flashcards covering key concepts and definitions related to complete blood counts, blood cell morphology, and bone marrow examination.

Hemoglobin

Main component of RBCs that transports O2 from the lungs to the tissues. Decreased levels are seen in anemias. Increased levels are seen in cancers, polycythemia, congenital heart disease.

Hematocrit

Ratio of the volume of erythrocytes to that of whole blood. Decreased levels are seen in blood loss/bleeding/hemorrhage and conditions affecting RBC production. Increased levels are seen in dehydration and exposure to high altitude.

Rule of Three

A rule applied only to normocytic, normochromic cells where RBC count x 3 = Hgb and Hgb x 3 = Hct.

RBC Count

Increased in polycythemias and decreased in anemias.

WBC Count

Increased in inflammatory diseases and leukemias/lymphomas. Decreased in radiation/chemotherapy.

Platelet Count

Increased in essential thrombocytosis and decreased in ITP/DIC.

MCV (Mean Corpuscular Volume)

Average volume of the RBC and is expressed in femtoliters (fL).

MCH (Mean Corpuscular Hemoglobin)

Average weight of hemoglobin in a RBC and is expressed in picograms (pg).

MCHC (Mean Corpuscular Hemoglobin Concentration)

Average concentration of Hgb in each individual red blood cell.

MEAN PLATELET VOLUME

Average volume of platelets. Increased value indicates larger than normal platelets and is seen in MDS, some myeloproliferative/hereditary disorders. Decreased value indicates smaller than normal platelets and is seen in aplastic anemia and bone marrow failure.

RED BLOOD CELL DISTRIBUTION WIDTH (RDW)

Measures the variation of RBC cell size or RBC volume. A normal RDW indicates that red cells are similar in size, while a high RDW indicates a greater variation in size of RBCs and is seen in patients with anemia and MDS.

WBC Differential Count - Relative Count

The percentage of each type of leukocyte that is present. Involves getting the percentage of each type of leukocyte and it involves the first 100 leukocytes identified.

WBC Differential Count - Absolute Count

The actual amount or number of a certain leukocyte in the blood sample. Calculated as (WBC x 1000) * (Relative leukocyte count/100).

Anisocytosis

Presence of red cells with abnormal sizes.

Poikilocytosis

Presence of red cells with abnormal shapes.

Microcyte

Smaller than normal cell; MCV usually <80 fL; has a central pallor; normochromic or hypochromic. Clinical conditions include iron deficiency anemia, thalassemias, lead poisoning, and anemia of chronic disease.

Macrocyte

Large cell, MCV usually >100 fL; usually normochromic; may be round or oval; cytoplasm is pink-red. Clinical conditions include liver disease, megaloblastic anemias, myelodysplastic syndromes, acute blood loss, and chemotherapy.

Hypochromic Cell

Cells possess a greater central pallor than normal; may lack hemoglobin and have a decreased MCHC or may be abnormally thin. Clinical conditions include iron deficiency anemia, thalassemia, anemia of chronic disease, sideroblastic anemia, and myelodysplastic syndromes.

Codocyte (Target Cell)

Bell shaped with thin wall having a greater than normal surface membrane to volume ratio; central area of hemoglobin, a clear ring, and a peripheral ring of hemoglobin giving an appearance of a bull's eye. Clinical conditions include hemoglobinopathies, thalassemia, obstructive liver disease, and iron deficiency anemia.

Dacryocyte (Teardrop Cell)

Pear-shaped cell with blunt pointed projection. Clinical conditions include extramedullary hematopoiesis, megaloblastic anemia, thalassemia, and hypersplenism.

Degmacyte (Bite Cell)

Semicircular area of cell removed by spleen; these cells may show multiple peripheral defects. Clinical conditions include drug-induced anemias, glucose-6-phosphate dehydrogenase deficiency, thalassemia, and unstable hemoglobinopathies.

Drepanocyte (Sickle Cell)

Elongated cell due to polymers of abnormal hemoglobin; terminal projections causing the cell to take on an irregular shape; usually lack a central pallor. Clinical condition is hemoglobinopathies.

Echinocyte (Burr Cell)

Cell with evenly distributed, short spicules; the spicules have a blunt end; retains central pallor. Clinical conditions include slow drying in high humidity, renal insufficiency, pyruvate kinase deficiency, stored blood, severe dehydration, and burns.

Acanthocyte

Spherical and densely stained cell with 3-12 spicules of uneven length and width around the surface. Clinical conditions include inherited lipid disorder, alcoholic cirrhosis, malabsorption states, neonatal hepatitis, and pyruvate kinase deficiency.

Keratocyte (Horn Cells)

Cell with projections (usually two) that resemble horns. Clinical conditions include microangiopathic hemolytic anemia, glomerulonephritis, Waring blender syndrome, and pyruvate kinase deficiency.

Ovalocytes/Elliptocytes

Oval-shaped cell; hemoglobin is concentrated at two ends; normal central pallor. Clinical conditions include hereditary elliptocytosis, iron deficiency anemia, myelophthisic anemia, megaloblastic anemia, thalassemia, sideroblastic anemia, and congenital dyserythropoietic anemia.

Schistocyte (Fragmented Red Cell)

Irregular shape or fragment of cell; results from damaged membrane. Clinical conditions include microangiopathic hemolytic anemias, traumatic hemolytic anemias, and Waring blender syndrome.

Spherocyte

Round cells; increased staining intensity with no central pallor; smaller volume than a normal cell. Clinical conditions include hereditary spherocytosis, immunohemolytic anemias, Heinz body hemolytic anemia, severe burns, and hypersplenism.

Stomatocyte

Cell having a slit-like area of central pallor. Clinical conditions include hereditary stomatocytosis, alcoholism, obstructive liver disease, cirrhosis and Rh-null disease.

Polychromatophilic Cells

Contains residual RNA, which stains diffusely blue; identified as reticulocyte when stained with a supravital dye. Clinical conditions include increased erythrocyte production, hemolytic anemias, membrane disorders, and hemolytic disease of the newborn.

Agglutination

Random masses or clusters of cells. Clinical conditions include exposure to a variety of antibodies, hemolytic anemia, atypical pneumonia, staphylococcal infections, trypanosomiasis and cold agglutinin disease.

Rouleaux Formation

Short or long stacks of cells resembling coins; often a blue-staining background. Clinical conditions include hyperproteinemia, multiple myeloma, macroglobulinemia, and increased fibrinogen.

Basophilic Stippling (Punctate Basophilia)

Coarse, deep blue inclusions; irregularly aggregated or clumped ribosomes throughout the cell; mitochondria and siderosomes may also aggregate. Clinical conditions include altered hemoglobin biosynthesis, lead intoxication, thalassemia, megaloblastic anemia, alcoholism, sideroblastic anemia, and pyrimidine-5'-nucleotidase deficiency.

Cabot Ring

Oval or figure-of-8-shaped inclusion; red-violet in color; usually one per cell; consists of nuclear remnants or part of the mitotic spindle. Clinical conditions include severe anemias and dyserythropoiesis.

Heinz Bodies

Round, refractile inclusions found on the periphery of the cell when stained with a supravital dye; consists of denatured globin produced by the destruction of Chemoglobin; they may occur in multiple numbers. Clinical conditions include drug-induced anemias, thalassemia, glucose-6-phophate dehydrogenase deficiency, and unstable hemoglobinopathies.

Howell Jolly Body

Round fragments of nucleus; reddish blue to deep purple in color; usually one per cell; represents chromosomes that have been separated from the mitotic spindle during abnormal mitosis. Clinical conditions include megaloblastic anemia, hemolytic anemias, hyposplenism, splenectomized persons, alcoholism and sickle cell anemia.

Pappenheimer Bodies

Small, irregular, pale blue to dark-staining granules; usually found on the periphery of cell and in groups; smaller than Howell-Jolly bodies; represent siderosomes, which stain positive with Perls Prussian blue stain and indicate iron content. Clinical Conditions include disturbed hemoglobin synthesis, sideroblastic anemia, dyserythropoietic anemias, thalassemia, and myelodysplastic syndromes.

Segmented Neutrophil

Size: 10-16 μ; Nucleus - 2-5 lobes connected by a very narrow filament; nuclear indentation is greater than one-half its diameter. Cytoplasm - Light pink to bluish with many small, evenly distributed pink to rose-violet granules. Clinical conditions: Infections, chronic neutrophilic leukemia, growth factor therapy, stress

Eosinophil

Size: 10-16 μ; Nucleus - 2-3 lobes. Cytoplasm - Pinkish-blue with many large, round, uniform reddish orange granules. Clinical conditions: Protozoan infections, allergic disorders, chronic myelocytic leukemia, Dermatitis, Hodgkin lymphoma, Chronic eosinophilic leukemia

Basophil

Size: 10-16 μ; Nucleus - 2 lobes usually obscured by granules. Cytoplasm - Pinkish-blue with few dark blue-black granules. Clinical conditions: Acute basophilic leukemia, Myeloproliferative neoplasms, Allergy and inflammation, AML with t(6;9)

Monocyte

Size: 14-21 μ; Nucleus - Horseshoe shaped or indented; nuclear folding may give the appearance of brainlike convolutions. Cytoplasm - Blue-gray, finely granular (ground glass) appearance. Clinical conditions: Myelodysplastic/myeloproliferative neoplasms and Severe infections

Lymphocyte

Size: 7-15 μ; Nucleus - Round or slightly indented, eccentric. Cytoplasm - Sky blue to deep blue. Contents: Scant and usually nongranular

Pelger-Huet Anomaly

Inherited as an autosomal dominant .A failure of normal segmentation of granulocytic nuclei Results in defects in scaffolding proteins that control the shape of the nuclear membrane* most nuclei are bilobed and round

Döhle Bodies

small, oval inclusions in the peripheral cytoplasm of polymorphonuclear neutrophils that stain pale blue with Wright's stain remnants of free ribosomes or rough-surfaced endoplasmic reticulum, persisting from an earlier stage of development

May-Hegglin Anomaly

pale-blue inclusions resembling Döhle bodies in neutrophils, by giant platelets and, in some persons, by thrombocytopenia inclusions are larger a rare autosomal-dominant condition involving the nonmuscle myosin heavy chain 9 gene(MYH9) linked to chromosome 22q12-13.

Alder-Reilly Anomaly

Dense, prominent, larger than normal azurophilic granulation in all white blood cells Seen in patients with mucopolysaccharidoses(e.g. Gargoylism, Hurler Syndrome)

Megakaryoblast

myeloid progenitor that develops into a megakaryocyte, which then produces platelets.