Comprehensive Hematology: Blood Components, Cell Types, and Morphology

What is the difference between serum and plasma?

Serum is without clotting factors; plasma is with clotting factors.

What is the most plentiful protein in plasma?

Albumin.

What percentage of plasma is water?

92%.

What substances are contained in serum?

Nutrients, glucose, proteins (specifically albumin), fats, electrolytes, immunoglobulins, clotting factors, enzymes, small amounts of CO2 and O2.

What are Acute Phase Reactants?

Substances that decrease their plasma concentration by at least 25% in response to cytokines.

What are the cellular concentrations in blood for erythrocytes?

Millions of cells per microliter.

What is the cellular concentration in blood for lymphocytes?

1000-10000s/mCL.

What is the cellular concentration in blood for thrombocytes?

100,000s/mCL.

Which blood cells do not follow the myeloid cell line of lineage?

Lymphocytes.

What does 'blasts' or 'stem cells' refer to?

Immature/progenitor cells that are always larger than their offspring.

What is the function of hemoglobin?

Carries O2 from the lungs to tissues and CO2 from tissues to lungs.

What are the components of hemoglobin?

4 units of heme and 4 units of globin.

What is the most common type of hemoglobin in adults?

Hemoglobin-A (two alpha, two beta).

What is the most common type of hemoglobin in fetuses?

Hemoglobin-F (two alpha, two gamma).

What is the significance of heme in hemoglobin?

Ferrous iron 2+ is in the center surrounded by the protoporphyrin complex.

What is the shape of erythrocytes?

Biconcave disc shape.

What is a reticulocyte?

An immature RBC with residual ribosomal RNA.

What indicates blood loss or destruction of RBCs?

A high number of reticulocytes in blood.

What are Howell Jolly bodies?

Inclusions of DNA remnants in RBCs.

What is basophilic stippling in RBCs?

Ribosomes stained blue that remain on the peripherals of a RBC.

What are Heinz bodies?

Denatured hemoglobin remains in RBCs.

What does it mean if RBCs are microcytic?

They are smaller than normal.

What does it mean if RBCs are macrocytic?

They are larger than normal.

What can cause macrocytic RBCs?

B12 and folate deficiency, alcoholism, Down syndrome, hypothyroidism, liver disease.

What does MCV stand for?

Mean corpuscular volume, the mean volume size of RBCs.

What does RDW stand for?

Red cell distribution width, indicating the distribution of sizes of RBCs.

What is anisocytosis?

High distribution of sizes of RBCs.

What indicates a mixture of macrocytosis and microcytosis?

Elevated RDW with normal MCV.

What are poikilocytosis?

Abnormal shapes of RBCs.

What are spherocytes?

Small, dense spheres of RBCs with increased osmotic fragility.

What are schistocytes?

Broken up, fragmented RBCs indicating destruction.

What are tear drop cells?

Tear drop shaped RBCs indicating extramedullary hematopoiesis.

What is sickle cell anemia?

A condition where RBCs are sickle shaped, clogging capillaries and causing organ damage.

What is rouleaux formation?

A stack of biconcave disc RBCs that are stuck together.

What does hypochromic mean?

RBCs that are more than ⅓ pale.

What does hyperchromic mean?

RBCs with no central pallor and super red.

What are granulocytes?

Also called polymorphonuclear cells, they include neutrophils, eosinophils, and basophils.

What is the most abundant type of leukocyte?

Neutrophils (60-70% of leukocytes).

What is eosinophilia?

Increased amount of eosinophils in the blood.

What is the mnemonic for causes of eosinophilia?

NAACP: Neoplastic, Asthma, Allergic reactions, Collagen vascular disease, Parasites.

What is the function of monocytes?

They can develop into macrophages and are better than neutrophils at alerting lymphocytes.

What are the two types of lymphocytes?

T cells and B cells.

What do T cells do?

Target infected or cancerous cells to destroy them.

What do B cells do?

Produce antibodies in response to learned foreign antigens.

What are natural killer (NK) cells?

Cells that automatically detect and kill cancer or virus-infected cells.

What indicates mononucleosis?

Atypical lymphocytes that are larger with bigger nuclei.

What do platelets originate from?

Megakaryocytes.

What is the function of platelets?

Involved in clotting and can release vasoactive compounds.

What indicates that platelets are being consumed too fast?

A lot of immature platelets in circulation.

What are reticulocytes?

Immature RBCs that contain residual ribosomal RNA.

What do Howell Jolly bodies indicate?

Inclusion of DNA remnants in RBCs.

What do schistocytes indicate?

Something is destroying RBCs.

What does hypochromic mean in terms of RBCs?

If more than ⅓ of the RBC is pale.

What does hyperchromic mean in terms of RBCs?

If the central pallor is gone and the RBC is super red.

What are the types of granulocytes?

Neutrophils, eosinophils, and basophils.

What do basophils produce?

Histamine, heparin, and IL-4.

What are monocytes?

7% of WBCs that can develop into macrophages.

What are lymphocytes?

35% of WBCs, including T cells and B cells.

What is the role of T cells?

Target infected or cancerous cells for destruction.

What is the role of B cells?

Produce antibodies in response to foreign antigens.

What are natural killer cells?

Cells that can automatically detect and kill cancer or virus-infected cells.

What do atypical lymphocytes indicate?

Usually indicates mononucleosis.

What are platelets?

Thrombocytes that originate from megakaryocytes and are involved in clotting.

What indicates a high number of immature platelets?

They are being consumed too fast for the bone marrow to produce more.

What are the cellular components of blood?

Water, fats, salts, carbs, gases, and proteins (specifically albumin)

Which blood cells are derived from the myeloid cell line? What one is not?

Derived from the myeloid line: Monocytes, Erythrocytes, Granulocytes, Thrombocytes; Not derived: Lymphocytes

Where do the different types of white blood cells mature?

T cells: thymus; B cells, monocytes, granulocytes: bone marrow

What are the two types of lymphocytes? Where does each live?

T cells and B cells; both live in the spleen and lymph nodes

What is the shape of a normal RBC?

A normal RBC is a biconcave disc.

What is at the center of a heme molecule?

Reduced ferrous iron.

How many heme units are in a hemoglobin molecule?

There are 4 heme units.

What does hemoglobin do?

Carries oxygen from the lungs to the tissues and CO2 from the tissues to the lungs.

How many globin molecules are in each hemoglobin molecule?

There are 4 globin molecules.

What are the breakdown products of hemoglobin?

Iron and globin are recycled; protoporphyrin ring becomes bilirubin and is excreted.

What are the 3 types of granulocytes? What does each do?

Eosinophils: defense against parasites and allergic reactions; Neutrophils: phagocytosis and destruction of pathogens; Basophils: produce histamine, heparin, and IL-4 for allergic reactions.

What is poikilocytosis?

Abnormal shape of a RBC.

What are ovalocytes? What do they signify?

Ovalocytes are abnormal RBCs that look like ovals; they signify B12 or folate deficiency.

What are schistocytes? What do they signify?

Broken, fragmented RBCs; signify hemolytic anemia.

What do teardrop shaped RBCs signify?

They signify RBCs are being made outside of the bone marrow (extramedullary hematopoiesis).

What is the normal coloration of a RBC?

⅓ of the cell is pale (central pallor).

What does hypochromasia mean?

More than ⅓ of a RBC is pale, signifies iron deficiency anemia.

What condition is hyperchromasia seen? Why?

Hyperchromasia is seen in spherocytes, caused by hereditary spherocytosis.

What are rouleaux and reticulocytes? When are they seen?

Rouleaux: stacked RBCs due to stickiness; Reticulocytes: immature erythrocytes seen in excess when RBCs are being destroyed.

When are nucleated RBCs seen?

When the bone marrow is under stress and cannot produce RBCs accurately.

What do Howell Jolly bodies signify?

Remnants of nuclear DNA in RBCs, signifies spleen is absent or dysfunctional.

When is basophilic stippling seen?

When ribosomes remain in RBCs, signifies lead poisoning, thalassemias, and alcohol abuse.

What are the two main types of WBCs?

Lymphocytes and natural killer cells.

What does an atypical lymphocyte look like, and what does it mean?

Atypical lymphocyte has a large nucleus and more cytoplasm; signifies mononucleosis.

What are the two types of neutrophils seen in the peripheral smear? When are immature forms seen?

Band cells and segmented neutrophils; immature forms are seen in bacterial infection or inflammation.

How many lobes do neutrophils usually have? What if there are more or less?

Typically 3-4 lobes; 5 or more indicates hypersegmentation (B12/folate deficiency), less than 3-4 indicates band cells.

How common are eosinophils? What are their distinguishing features?

1-3% of WBCs; bilobed nuclei that stain red.

What conditions cause eosinophilia?

Neoplastic, allergic reactions, asthma, collagen vascular disease, parasites.

How common are basophils? What are their distinguishing features?

<1% of WBCs; large blue granules, cannot see nucleus but has bilobed.

When can basophilia be seen?

In hypersensitivity reactions, hypothyroidism, infections like TB, viruses, and parasites.

What do monocytes look like and what do they do? What do they turn into in tissue?

Monocytes look like butt cells; they perform phagocytosis and turn into macrophages in tissue.

What are the distinguishing features of platelets? Where do they come from?

Very small, anucleate cells in the blood; they come from megakaryocytes.

What are the risks of thrombocytopenia?

Low platelet counts can cause risk of bleeding.

What is the significance of large platelets?

Large platelets are immature, indicating faster consumption than production.

What can cause a falsely low platelet count?

If platelets clot while reading the blood, they are not counted.