Morphology of Red Blood Cells

Flashcards covering the vocabulary of red blood cell morphology, indices, inclusions, and associated pathological states based on lecture notes.

Anisocytosis

An abnormal variation in Red Blood Cell ($RBC$) volume and diameter.

Poikilocytosis

An abnormal variation in the shape of Red Blood Cells ($RBCs$).

Microcytes

Red cells characterized by a decrease in size, smaller than $6\,\mu\text{m}$ in diameter with an $MCV < 80\,fL$.

Macrocytes

Red cells characterized by an increase in size, larger than $8\,\mu\text{m}$ in diameter with an $MCV > 100\,fL$.

Normocytic

A descriptive term applied to Red Blood Cells ($RBCs$) of normal size, ranging from $7.0$-$8.0\,\mu\text{m}$.

Normochromic

A descriptive term for a Red Blood Cell ($RBC$) with a normal concentration of hemoglobin and normal central pallor.

Hypochromic

A descriptive term for a Red Blood Cell ($RBC$) with a decreased concentration of hemoglobin and increased central pallor.

Mean Cell Volume (MCV)

The average volume of Red Blood Cells ($RBCs$) expressed in femtoliters ($fL$), calculated as $\frac{Hct (\%) \times 10}{RBC\,count}$.

Mean Cell Hemoglobin (MCH)

The average weight of hemoglobin in a Red Blood Cell ($RBC$) expressed in picograms ($pg$), calculated as $\frac{Hb (g/dL) \times 10}{RBC\,count}$.

Mean Cell Hemoglobin Concentration (MCHC)

The average concentration of hemoglobin in each individual erythrocyte, expressed in $g/dL$ or $\%$, calculated as $\frac{Hb (g/dL) \times 100}{Hct}$.

Red Cell Distribution Width (RDW)

A measure of the variation in red blood cell size or volume, used to help determine the causes of anemia.

Reticulocyte Production Index (RPI)

An index that adjusts the reticulocyte count for the degree of anemia and the premature release of reticulocytes from the bone marrow.

Acanthocytes

Small, dense Red Blood Cells with few irregularly spaced projections of varying length, also known as spur cells.

Burr Cells

Red cells with blunt or pointed, short, evenly spaced projections over the surface, also known as echinocytes.

Elliptocytes

Red cells that are elliptical (cigar-shaped) or egg-shaped, also known as ovalocytes.

Schistocytes

Fragmented Red Blood Cells caused by rupture in the peripheral circulation, also known as schizocytes.

Helmet Cells

Fragmented Red Blood Cells that appear cup-shaped or like helmets, also known as keratocytes.

Sickle Cells

Thin, dense, elongated Red Blood Cells pointed at each end, which may appear curved or crescent-shaped.

Spherocytes

Small, round, dense Red Blood Cells with no central pallor.

Stomatocytes

Red Blood Cells characterized by a slit-like or mouth-like area of central pallor.

Target Cells

Red cells with hemoglobin concentrated in the center and around the periphery, resembling a target, also known as codocytes.

Tear Drop Cells

Red cells with a single pointed extension resembling a teardrop or pear, also known as dacryocytes.

Howell-Jolly Bodies

Round, dense, dark blue-purple granules composed of $DNA$ (nuclear fragments).

Pappenheimer Bodies

Irregular clusters of small, blue granules composed of iron, often found near the periphery of the cell.

Basophilic Stippling

Fine or coarse punctate granules distributed throughout the cytoplasm composed of precipitated $RNA$.

Heinz Bodies

Inclusion bodies composed of denatured hemoglobin, visible only with supravital stains.

Cabot Rings

Blue rings or figure-eight loops representing mitotic spindle remnants.

Anemia

A pathological state where the blood is unable to supply tissues with adequate oxygen for proper metabolic function.

Peripheral Blood Film

A laboratory tool that serves as a quality control to verify results from automated analyzers and evaluate $RBC$ morphology.

Absolute Reticulocyte Count

A direct measure of red blood cell production representing the number of reticulocytes in a volume of blood.

Corrected Reticulocyte Percentage

An adjustment to the reticulocyte percentage to account for the degree of anemia, also known as the reticulocyte index ($RI$).

Polychromasia

The presence of young, non-nucleated blue-gray Red Blood Cells, which are typically reticulocytes.

Rouleaux

An arrangement of Red Blood Cells where they appear stacked like coins.

Agglutination

The clumping of Red Blood Cells, typically due to antigen-antibody reactions.

HbSC Crystals

Hand-in-glove or finger-like erythrocyte crystals found in Hemoglobin $SC$ disease.

Plasmodium spp.

Parasites transmitted by mosquitoes that infect red cells and can be a cause of hemolytic anemia.

Megaloblastic Anemia

A macrocytic anemia often associated with folate or $Vitamin\,B_{12}$ deficiency and oval macrocytes.

Sideroblastic Anemia

A type of microcytic anemia often associated with the presence of Pappenheimer bodies.

Uremia

A clinical condition often associated with the presence of Burr cells (echinocytes) on the blood film.

Hereditary Spherocytosis

A genetic condition characterized by the production of small, round, dense Red Blood Cells lacking central pallor.