99069_ch06_6101.pdf

C hapter

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Hematology

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© Jones & Bartlett Learning, LLC NOT FOR SALE OR DISTRIBUTION Outline

6

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© Jones & Bartlett Learning, LLC NOT FOR SALE OR DISTRIBUTION KEY TERMS

Agglutination: The clumping of red blood cells following a Introduction transfusion reaction. Hematology Agranulocytes: Leukocytes without granular cytoplasm. Red Blood Cells Albumins: The smallest of plasma make up Learning, LLC White Blood Cells© Jones & Bartlett Learning, LLC © proteins; Jonesthey & Bartlett around 60% of these proteins NOT by weight. Platelets FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION Antibodies: Agglutinins; gamma globulin proteins that respond Plasma to specific antigens. Hemostasis Antigens: Agglutinogens; red blood cell surface molecules Serum that react with antibodies from the plasma. Plasma Basophils: Leukocytes fewer granules than Appearance of Serum and Plasma © Jones & Bartlett Learning, LLC © Jonesthat&have Bartlett Learning, LLC eosinophils, which become deep blue in basic stain. Blood Clotting NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION B cells: Lymphocytes that are responsible for humoral Blood Types and Transfusions immunity. Summary Bilirubin: An orange pigment formed from biliverdin that has Critical Thinking potent antioxidant activity; bilirubin is orange and excreted Websites along with biliverdin in the bile. Review Questions

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© Jones & Bartlett Learning, LLC Biliverdin: A green pigment created from decomposing heme, NOT FOR SALE OR which is converted to DISTRIBUTION bilirubin. Coagulation: The formation of a blood clot.

After studying this chapter, readers should be able to: Colony-stimulating factors (CSFs): Glycoproteins that can 1. Distinguish between the formed elements and the cause the proliferation and differentiation of leukocytes. liquid portion of the blood. Embolus: A clot that dislodges or fragments, to be carried 2. Explain the characteristics of red blood cell counts. © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC away in the blood flow. 3. Describe erythropoiesis and the sites of production Eosinophils: Leukocytes with coarse, granules NOTsame-sized FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION of erythropoietin. that appear dark red in acid stain. 4. Distinguish between the five types of white blood Erythropoiesis: The process of developing erythrocytes (red cells and discuss their functions. blood cells), which mostly occurs in the red bone marrow 5. Describe the functions of each of the major (myeloid tissue). components of blood plasma. Erythropoietin: A hormone uses negative feedback LLC to © Jones & Bartlett Learning, LLC © Jones &that Bartlett Learning, 6. Describe the characteristics of platelets and their control the rate of red blood cell formation. NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION functions. Fibrin: Insoluble threads of protein made from the plasma 7. Define hemostasis and explain the mechanisms protein fibrinogen. that help achieve it. Fibrinogen: A plasma protein that is important for blood 8. Explain what prevents the formation of massive coagulation. It is the largest plasma protein. clots throughout the cardiovascular system. Globulins: Antibodies made by the liver or lymphatic tissues © Jones & Bartlett 9. ExplainLearning, blood typingLLC and how it is used to avoid © Jones & Bartlett Learning, LLC that make up around 36% of the plasma proteins. reactions to blood transfusions. NOT FOR SALEadverse OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION 10. Distinguish between a thrombus and an embolus. © Jones and Bartlett Publishers. NOT FOR SALE OR DISTRIBUTION

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CHAPTER 6  Hematology

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© Jones & Bartlett Learning, LLC nitrogenous substances: Amino acids, urea, and NOTNonprotein FOR SALE OR DISTRIBUTION

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uric acid in the plasma. Granulocytes: Leukocytes with granular cytoplasm, including Plasma: The liquid portion of blood. neutrophils, eosinophils, and basophils. Plasma cells: Specialized B cells that form and secrete Hematocrit (HCT): The volume percentage of red blood cells antibodies. in a sample of whole blood. Plasma proteins: The most abundant solutes (dissolved Hematology: The study blood and&blood disorders. ©ofJones Bartlett Learning, LLC © Jones & Bartlett Learning, LLC substances) in the plasma. Hemoglobin: The substance red blood cells that NOT FOR SALE ORofDISTRIBUTION NOT inFOR SALE ORcarries DISTRIBUTION Platelets: Thrombocytes; platelets are cytoplasm fragments oxygen. megakaryocytes that are important in blood clotting. Hemostasis: The stoppage of bleeding. Polymorphonuclear leukocytes: White blood cells with Interleukins: Hormones upon which many of the effects of segmented lobular nuclei, such as neutrophils. leukocytes depend. Prothrombin: An alpha globulin made in the liver that is Leukocytes: White cells; they protect theLLC body against © Jones & blood Bartlett Learning, © Jones & Bartlett Learning, LLC converted to thrombin. disease and develop from hemocytoblasts in red bone NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR Red blood cells (erythrocytes): Those redDISTRIBUTION blood cells that marrow. transport gases, including oxygen. Leukocytosis: A condition of white blood cells exceeding Serotonin: A substance that contracts smooth muscles in 10,000 per cubic millimeter (microliter), indicating an acute blood vessels, reducing blood loss. infection. Serum: The clear, yellowish liquid that remains after clot Leukopenia: A condition of the total white blood cell count © Jones & Bartlett Learning, LLC © Jones & Bartlett LLC and some, but formation; serum is Learning, plasma minus fibrinogen being below 5,000 per cubic millimeter (microliter); this not all, of its clotting factors. NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION signifies conditions such as influenza, AIDS, and others. T cells: Lymphocytes that are responsible for cell-mediated Lymphocytes: Leukocytes with large, round nuclei inside a immunity. thin cytoplasm rim. Thrombin: A substance that causes fibrinogen to be cut into Macrophages: Cells that phagocytize and destroy damaged sections of fibrin and then joined into long threads as part of red blood cells, mostly in the liver and spleen. the clotting process. Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC Mast cells: Connective©tissue cells that, during allergic Thrombocytes: See platelets. reactions, release histamine and heparin. NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION Thrombopoietin: A hormone that causes megakaryocytes to Megakaryocytes: Red bone marrow cells that fragment to develop from hemocytoblasts, resulting in eventual platelet produce platelets. (thrombocyte) formation. Monocytes: Leukocytes that are the largest type of blood Thrombus: A clot that forms abnormally in a vessel. cells, with varied nuclei. Vasospasm: action of muscle contraction in a small blood Natural killer (NK) cells: Lymphocytes responsible © Jones & Bartlett Learning, LLCfor ©AnJones & Bartlett Learning, LLC vessel that occurs after it is cut or broken; this action can immune surveillance; they are important in preventing NOT FOR SALE OR DISTRIBUTION NOT FOR ORvessel. DISTRIBUTION completely close the endsSALE of a severed cancer. White blood cells: See leukocytes. Neutrophils: Leukocytes with small granules that appear light purple in neutral stain; older neutrophils are called segs while younger neutrophils are called bands.

© Jones & Bartlett Learning, LLC © Jones &approximately Bartlett Learning, LLC wastes (see Figure 6–1). An average adult has NOT FOR SALE OR DISTRIBUTION FOR SALE 4 to 6 L of blood. The blood is made upNOT of cells, fragments of OR cells, DISTRIBUTION and dis-

Introduction

solved biochemicals containing nutrients, oxygen, hormones, Hematology and wastes. It helps to distribute body heat and maintain Hematology is the branch of medicine that is concerned with stable interstitial fluid. Blood is actually a connective tissue the study of blood and blood disorders. The blood transports with its cells suspended in a liquid, extracellular matrix. It © Jones & Bartlett Learning, LLC erythro- oxygen, nutrients, © Jones & waste Bartlett Learning, LLC cellular products, and hormones is heavier and thicker than water. Blood contains NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION throughout the body. It is involved in heat distribution, procytes (red blood cells), platelets, and leukocytes (white blood tection against infection, and the regulation of acid–base cells). Red blood cells (RBCs), white blood cells (WBCs), and balances. Hematology is a major component of the clinical platelets are collectively called formed elements. The liquid laboratory. Phlebotomists must be familiar with the composiportion of blood is called plasma. Blood volume represents about 7% of a person’s body weight. tion and normal values of the blood. They must also under© Jones & Bartlett Learning, © Jones & Bartlett LLC Plasma contains water, LLC amino acids, carbohydrates, lipstand common bloodLearning, diseases and conditions. This chapter ids, proteins, electrolytes, vitamins, and cellular examine the structure and functions of the blood, which NOT FOR SALE OR hormones, DISTRIBUTION NOTwill FOR SALE OR DISTRIBUTION © Jones and Bartlett Publishers. NOT FOR SALE OR DISTRIBUTION

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Hematology

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© Jones & Bartlett Learning, LLC NOT FOR SALE OR DISTRIBUTION Withdraw blood

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© Jones & Bartlett Learning, LLC White blood cells NOT FOR SALE OR DISTRIBUTION Red blood cells

Plasma (55% of whole blood)

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White blood cells© andJones & Bartlett Learning, LLC platelets (<1% ofNOT whole blood) FOR SALE OR DISTRIBUTION Red blood cells (45% of whole blood)

Centrifuge

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Hematocrit

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Figure 6–1  The composition of whole blood

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Jones fluid & Bartlett Learning, LLCcells susis a© specialized connective tissue containing NOTin FOR SALE OR DISTRIBUTION pended a fluid matrix.

Jonesproteins & Bartlett Learning, RBCs cannot©synthesize or divide to form moreLLC cells. NOT SALE ORbecause DISTRIBUTION They produce ATPFOR through glycolysis they do not have mitochondria, and they use none of the oxygen carried Red Blood Cells in their hemoglobin. Red blood cells (erythrocytes) have a biconcave shape, A red blood cell count is the number of RBCs in a micromeaning that they are basically round, with a center that is liter of blood. Normal ranges of RBCs are as follows: ■■ Adult comparison with their edges. They are approximales: 4.6Learning, million to 6.2LLC million cells per micro© Jones & depressed BartlettinLearning, LLC © Jones & Bartlett liter mately 7.5 micrometers (mm) in diameter and 2 mm thick at NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION ■■ Adult females: 4.2 million to 5.4 million cells per microthe rim. This shape helps them to transport gases by increasliter ing the surface area of the cell, allowing greater diffusion (see Increased numbers of circulating RBCs increase the blood’s Figure 6–2). oxygen-carrying capacity, which can affect health. Red The shape of erythrocytes also ensures that the cell mem(which carries oxygen) blood cell counts are taken to © diagnose many diseases and brane is nearer to the©hemoglobin Jones & Bartlett Learning, LLC Jones & Bartlett Learning, LLC inside the cell. The cytoplasm of an RBC consists mainly of evaluate their courses. However, the opposite is also true: FORoxygen-carrying SALE OR DISTRIBUTION NOT FOR DISTRIBUTION a 33% solution of hemoglobin. This SALE is the redOR pigment that decreased RBC counts lead toNOT decreased gives an RBC its color and name. Erythrocytes make up about capacity, which is more likely to be seen on a regular basis 45% of blood volume—this portion is known as the hemathan increased counts. tocrit (HCT). When it binds with oxygen, oxyhemoglobin In humans, RBCs are mostly developed in spaces within is formed. Oxyhemoglobin is bright red. When oxygen is bones that are filled with red bone marrow (myeloid tissue). © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC released, deoxyhemoglobin is formed. Deoxyhemoglobin is This process is called erythropoiesis. Erythrocytes usually NOT FOR SALE OR DISTRIBUTION NOT FOR SALEcells ORcreated DISTRIBUTION live for 120 days, with replacement to maintain a darker red, and blood rich in deoxyhemoglobin may appear relatively stable RBC count. The rate of red blood cell formabluish when seen through blood vessels. The cytoplasm of tion is controlled by negative feedback via the hormone erytherythrocytes contains an enzyme, carbonic anhydrase (CAH), ropoietin. It is released by the kidneys and liver in response that catalyzes the reaction of carbon dioxide (CO2) plus water (H2O) into hydrogen (H2) and carbon trioxide (CO3). to prolonged oxygen deficiency (see Figure 6–3). © Jones & Bartlett Learning, LLC © Jones & Bartlett LLC Erythrocytes have nuclei that are shed as they mature, Production of red Learning, blood cells (erythropoiesis) continues allowingOR moreDISTRIBUTION room for hemoglobin. Lacking nuclei, mature a heightened the amount of them in the blood NOT FOR SALE NOTatFOR SALErate ORuntil DISTRIBUTION © Jones and Bartlett Publishers. NOT FOR SALE OR DISTRIBUTION

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CHAPTER 6  Hematology

© Jones & Bartlett Learning, LLC Erythrocytes 98% NOT FOR SALE OR DISTRIBUTION

Low blood oxygen LLC © Jones & Bartlett Learning, NOT FOR SALE OR DISTRIBUTION

Stimulation Inhibition

Leukocytes 2% Erythromyeloid lineage Kidneys

Liver

• Granular leukocytes

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Neutrophils 45–74% of leukocytes

Erythropoietin

Basophils <1% of leukocytes

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Increased

oxygen- LLC © Jones &Release Bartlett Learning, carrying NOT FORinto SALE OR DISTRIBUTION capacity bloodstream

Eosinophils 1–5% of leukocytes

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• Monocytes 3–11% of leukocytes

© Jones & Bartlett Learning, LLC Release NOT FOR SALE OR DISTRIBUTION into bloodstream Red bone marrow

Lymphoid lineage 20–47% of leukocytes • T cells

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© Jones & Bartlett Learning, LLC Increased number of NOTredFOR SALE OR DISTRIBUTION blood cells

• B cells

© Jones & Bartlett Figure 6–2  Various blood cells

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Figure 6–3  Erythropoietin is released by the kidneys and liver is response to prolonged oxygen © Jones &deficiency. Bartlett Learning, LLC

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circulation is enough to supply oxygen to the body tissues. iron at 10 times the normal rate, building up to toxic levels. The stages of formation of RBCs and other blood cells from This is treated by periodic blood removal. hemocytoblasts are shown in Figure 6–4. Red blood cells bend as they move through blood vessels, B-complex vitamins such as vitamin B12 and folic acid but aging causes them to become more © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLCfragile. Cells called macrophages phagocytize and destroy damaged red blood greatly influence RBC production and are necessary for DNA NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION cells, mostly in the liver and spleen. Hemoglobin from RBCs is synthesis. Hematopoietic (blood-cell-forming) tissue is very broken down into heme, which contains iron, and the protein vulnerable to deficiency of both of these vitamins. Iron is globin. The heme then decomposes into iron and biliverdin, required for normal red blood cell production and for hemoa green pigment. The blood may transport the iron to synglobin synthesis. Iron is slowly absorbed from the small intesthesize new hemoglobin. Most©ofJones the iron & thatBartlett is removed tine, and the body reuses much of&the iron released by the © Jones Bartlett Learning, LLC Learning, LLC from degraded hemoglobin is recycled to the bone marrow. decomposition of hemoglobin from damaged RBCs. Only NOT ,FOR SALE OR DISTRIBUTION FOR OR an orange pigment, Biliverdin is converted into bilirubin small amounts of ironNOT must be takenSALE in via the diet.DISTRIBUTION and excreted along with biliverdin in the bile. The life cycle Anemia has various causes, but sometimes it is caused by of RBCs is summarized in Figure 6–5. too little hemoglobin, or by too few RBCs. People with anemia may appear pale and lack energy because their blood is White Blood Cells not able to carry enough oxygen. Iron-rich foods are impor© Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC Leukocytes, also known as white blood cells, protect the tant for the pregnant woman especially, in order to supply NOT FOR SALE OR DISTRIBUTION FOR OR DISTRIBUTION body againstNOT disease and SALE develop from hemocytoblasts in enough oxygen to her blood supply as well as to the blood the red bone marrow in response to hormones. These horsupply of the developing fetus. However, not all anemia is mones are either interleukins or colony-stimulating factors due to iron deficiency. Because a pregnant woman’s blood (CSFs). Interleukins are organized by number, while most of volume will increase due to fluid retention that supports the the CSFs are named for the type of cells they stimulate. White fetus, it decreases her hematocrit levels. Hemochromatosis is © Jones & aBartlett Learning, LLC to increased RBCs. It is an © Jones & Bartlett Learning, blood cells are transported to sites ofLLC infection and may then condition that involves normal theSALE bloodstream. iron handling disorder in which the small intestine absorbs NOT FOR SALE OR DISTRIBUTION NOTleave FOR OR DISTRIBUTION © Jones and Bartlett Publishers. NOT FOR SALE OR DISTRIBUTION

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Hematology

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© Jones & Bartlett In red boneLearning, LLC marrow NOT FOR SALE OR DISTRIBUTION

Hemocytoblast

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Myeloid stem cell

Lymphoid stem cell

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Proerythroblast © Jones & Bartlett Learning, LLCMegakaryoblast NOT FOR SALE OR DISTRIBUTION

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Monoblast Lymphoblast ©Myoblast Jones & Bartlett Learning, LLC NOT FOR SALE OR DISTRIBUTION

Early erythroblast

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Promonocyte

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Promegakaryocyte Late erythroblast

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Basophilic Neutrophilic NOT myelocyte myelocyte myelocyte

Normoblast

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Reticulocyte In circulating blood

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Erythrocyte

Thrombocytes (platelets)

Eosinophil

Basophil

Neutrophil

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Monocyte

T lymphocyte

B lymphocyte

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Figure 6–4  The stages of formation of the blood cells from hemocytoblasts

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CHAPTER 6  Hematology

1 Food nutrients including © Jones & Bartlett Learning, LLC B12, folic acid and vitamin iron are absorbed from NOT FOR SALE OR DISTRIBUTION Bloodstream small intestine.

There are usually five types of WBCs in circulating blood, © Jones & Bartlett Learning, LLC differing in size, cytoplasm nature, nucleus shape, and stainNOTing FOR SALE OR DISTRIBUTION characteristics. Leukocytes with granular cytoplasm are

called granulocytes, while those without granular cytoplasm are called agranulocytes. Most granulocytes are about twice as large as a red blood cell, including eosinophils, basophils, Small and neutrophils. Granulocytes also develop in the red bone intestine © Jones & Bartlett Learning, LLC Jones & 12 Bartlett Learning, LLC marrow, as RBCs do, but they © only live about h. NOT FOR SALE OR NOT FOR SALE OR DISTRIBUTION Neutrophils have small granules that appear light purple inDISTRIBUTION neutral stain. Older neutrophils (sometimes called segs) have lobed nuclei in two to five segments connected by thin chromatin strands. Younger neutrophils have C-shaped nuclei and are called bands (see Figure 6–4). This structure has given 2 Nutrients are transported © Jones & Bartlett Jones Bartlett Learning, LLC, leukocytes neutrophils © other names:&polymorphonuclear through Learning, the bloodstreamLLC to the red DISTRIBUTION bone marrow. polymorphs,NOT or even polys.SALE Neutrophils highly mobile, NOT FOR SALE OR FOR OR are DISTRIBUTION and usually they are the first type of WBCs to arrive at the site of any injury. These active cells specialize in attacking Red bone and digesting bacteria. Neutrophils make up 54 to 62% of marrow the leukocytes in most adults. Most have short lifeLLC spans, surviving in the © Jones & Bartlett Learning, LLC © Jones & neutrophils Bartlett Learning, bloodstream for only about 10 h. When they actively engulf NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION debris or pathogens, they may live for 30 min or less. A neutrophil will die after engulfing one to two dozen bacteria. As neutrophils break down, they release chemicals that attract other neutrophils to their location. A mixture of dead neutrophils and cellular debris products forms pus, which is © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC associated with infected wounds. NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION Eosinophils have coarse, same-sized granules that appear dark red in acid stain (see Figure 6–4). Their nuclei have 3 Red blood usually just two lobes (therefore, they are called bilobed), cells arise from and they make up only 2 to 4% of circulating leukocytes. less specialEosinophils are particularly effective against multicellular ized progenitor © Jones & Bartlett Learning, LLC © Jones & parasitic Bartlettworms, Learning, LLC parasites such as flukes or which are too cells. NOT FOR SALE OR DISTRIBUTION NOT FOR SALEinfection, OR DISTRIBUTION large to engulf. During a parasitic the number of Red blood cell (erythrocyte) circulating eosinophils increases dramatically. These cells are sensitive to circulating allergens (materials that trig4 Mature red blood cells are released into the ger allergies) and are also attracted to sites of injury. Once bloodstream and circulate for about 120 arriving at these sites, eosinophils release enzymes that days. mast cells and neutroreduce& theBartlett degree of Learning, inflammation LLC © Jones & Bartlett Learning, LLC © Jones phils produce. NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION Basophils are smaller than neutrophils or eosinophils and Liver have lower amounts of granules. They are more irregular and become deep blue in basic stain (see Figure 6–4). They usually account for less than 1% of circulating leukocytes. Basophils migrate to injury sites and cross capillary endothelium Hemoglobin © Jones & Bartlett Learning, LLC © the Jones & Bartlett Learning, LLC to accumulate in the damaged tissues, where they release SALE(a OR NOT FOR SALE OR DISTRIBUTION histamine (which dilates bloodNOT vessels)FOR and heparin com- DISTRIBUTION Globin Heme pound that prevents blood clotting). Mast cells release the same compounds in damaged connective tissues. Mast cells Amino acids Iron Biliverdin and basophils exist in distinct populations but have separate origins. © Jones & Bartlett Bilirubin Learning, LLC © Jones & Bartlett Learning, LLC Monocytes are the largest type of blood cell, exisiting up 5 Iron from heme is NOT FOR SALE OR DISTRIBUTION SALE to twice as NOT large asFOR red blood cellsOR (see DISTRIBUTION Figure 6–4). They 6 Bilirubin is secreted into returned to red have nuclei that may be kidney-shaped, lobed, oval, or round. bone marrow via small intestine and Monocytes usually make up 2 to 8% of circulating leukocytes, the bloodstream. excreted. Amino acids having phagocytic properties prior to movement to the tisfrom globin are returned to circulation. sues. An individual monocyte is transported through the © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC bloodstream, remaining in circulation for only about 24 h tissues. Here, a monocyte becomes NOT FOR SALE OR DISTRIBUTION NOTbefore FORentering SALEperipheral OR DISTRIBUTION Figure 6–5  The life cycle of RBCs a tissue macrophage. Macrophages are aggressive phagocytes © Jones and Bartlett Publishers. NOT FOR SALE OR DISTRIBUTION

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Hematology

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the number of eosinophils to increase. AIDS causes certain that often attempt to engulf items as large as (or larger than) © Jones & Bartlett Learning, LLC © Jones &themselves. Bartlett When Learning, LLC types of lymphocyte counts to drop sharply. phagocytically active, they release chemiNOT FOR SALE OR DISTRIBUTION NOT FOR SALE DISTRIBUTION cals that OR attract and stimulate neutrophils, monocytes, and

Platelets other phagocytic cells. Lymphocytes are usually only a little larger than RBCs, Platelets are also known as thrombocytes. They are cytowith large, round nuclei inside a thin cytoplasm rim (see plasm fragments arising from red bone marrow cells (called megakaryocytes). Megakaryocytes develop from hemocyFigure 6–4). Lymphocytes make up between 20 and 30% of ©Lymphocytes Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC thromtoblasts (megakaryoblasts) because of the hormone circulating leukocytes. continuously migrate NOT FOR SALE OR NOT FOR SALE OR DISTRIBUTION bopoietin. Platelets lack nuclei and are not even one-half theDISTRIBUTION from the bloodstream into the peripheral tissues and back size of RBCs. They live for about 10 days and are capable of into the bloodstream. Circulating lymphocytes constitute amoeboid movement. Usually, platelet counts range from only a small fraction of all lymphocytes, and the major130,000 to 400,000 per microliter. The function of plateity of lymphocytes are in other connective tissues in lymlets is primarily to block injuries to damaged blood vesphatic organs. Lymphocytes are vital for immunity. Some © Jones & Bartlett LLC foreign © Jones Bartlett Learning, sels and to start forming&blood clots. Therefore, the LLC main of them produce antibodies Learning, that attack certain event of theNOT plateletFOR phaseSALE is the formation of the platelet substances. NOT FOR SALE OR DISTRIBUTION OR DISTRIBUTION plug. Table 6–1 lists the characteristics of RBCs, WBCs, Circulating blood contains three functional classes of and platelets. lymphocytes, which cannot be distinguished with a light microscope, as follows: Plasma 1. T cells are responsible for cell-mediated immunity, Plasma&suspends theLearning, cells and platelets which is a specific defense mechanism that combats © Jones & Bartlett Learning, LLC © Jones Bartlett LLCof the blood. It is a clear, straw-colored liquid made up of 92% water, with organic invading foreign cells and tissues. T cells either enter NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION and inorganic biochemicals. Plasma is close to the same denperipheral tissues and attack foreign cells directly or sity as water. Plasma makes up 46 to 63% of the volume of control the activities of other lymphocytes. 2. B cells are responsible for humoral immunity, which is whole blood. It helps to transport gases, nutrients, and vitaa specific defense mechanism that involves the producmins while helping to regulate fluid and electrolyte balance tion and distribution of antibodies. These antibodies as well as pH levels. Plasma proteins are the most abundant © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC of the solutes (dissolved substances) in the plasma. They are attack foreign antigens throughout the body. Activated NOTremaining FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION not usually used as energy sources, in the blood B cells differentiate into plasma cells, which are specialized to form and secrete antibodies. and interstitial fluids. Three primary classes of plasma pro3. Natural killer (NK) cells are responsible for immune teins exist: albumins, globulins, and fibrinogen. These three surveillance, which involves the detection and subseclasses make up more than 99% of the plasma proteins. The quent destruction of abnormal tissue cells. NK cells remainder consists of circulating enzymes, hormones, and © Jones & known Bartlett Learning, LLC © Jones & Bartlett Learning, LLC (sometimes as large granular lymphocytes) are prohormones. NOT FOR inSALE ORcancer. DISTRIBUTION SALE OR DISTRIBUTION AlbuminsNOT are theFOR smallest of the plasma proteins, but they important preventing make up around 60% of these proteins by weight. They are Normally, there are 4,500 to 10,000 white blood cells in a made in the liver and play an important role in the plasma’s microliter of human blood. This is called a white blood cell osmotic pressure. Because plasma proteins are too large to count (WBC count). White blood cell counts are of interest move through capillary walls, they create an osmotic presto determine the clinical conditions of patients. If the WBC sure to& hold water in the capillaries (known is higher than normal, there may be an infection. © If Jones © Jones & count Bartlett Learning, LLC Bartlett Learning, LLC as colloid osmotic 3 ) (microliter, pressure). This helps regulate water movement WBCs exceed 10,000 per cubic millimeter (mm NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION between blood or mL), the condition is called leukocytosis, which may indiand tissues, to aid in controlling blood volume and blood cate an acute infection. It is important to note that microlipressure. Albumins are also important in the transport of ters are now being used more than cubic millimeters for this fatty acids, thyroid hormones, some steroid hormones, and type of measurement, with 1 mL equivalent to 1 mm3. Also, other substances. Globulins (including alpha,© beta, and gamma globulins) normal ranges of WBC counts vary slightly from hospital to © Jones & Bartlett Learning, LLC Jones & Bartlett Learning, LLC make up around 35% of the plasma proteins. Important hospital. Conditions such as leukemia may also be noted as NOTand FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION plasma globulins include antibodies transport globulins. a result of WBC counts. Antibodies, also called immunoglobulins, attack foreign proAppendicitis is an example of an acute infection that an teins and pathogens. Transport globulins bind small ions and elevated WBC may signify. When the WBC count is greatly hormones. Alpha and beta globulins are made by the liver to elevated, leukemia may exist. Leukopenia is defined as a total WBC count below 5,000 per cubic millimeter (microtransport lipids and fat-soluble vitamins. Gamma globulins © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC liter). It may be more associated with immune suppression are made by the lymphatic tissues and are a type of antibody. NOT FOR SALE OR DISTRIBUTION NOT FOR SALE DISTRIBUTION Fibrinogen (making up around 4% ofOR the plasma proteins) is or chemotherapy-related diseases. Leukopenia is associated important for blood coagulation. It is made in the liver and is with diseases such as influenza, measles, mumps, chicken the largest (in size) of the plasma proteins. Table 6–2 sumpox, AIDS, poliomyelitis, and typhoid fever. marizes albumin, globulin, and fibrinogen. Percentages of the types of leukocytes in a blood sample Oxygen and carbon dioxide are the most important blood are listed in a differential white blood cell count (diff), which © Jones & isBartlett Learning, LLCof condition that exists with © Jones & Bartlett Learning, gases, with nitrogen also containedLLC in the plasma. Plasma useful to determine the type include OR amino acids, nucleotides, lipids, and simgreater accuracy. Bacterial infections usually cause neutrophil NOT FOR SALE OR DISTRIBUTION NOTnutrients FOR SALE DISTRIBUTION ple sugars absorbed from the digestive tract. Glucose is counts to increase, while certain parasitic infections cause © Jones and Bartlett Publishers. NOT FOR SALE OR DISTRIBUTION

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CHAPTER 6  Hematology

Characteristics of Blood Cells and Platelets © Jones & Bartlett Learning, LLC ■Table 6–1 Learning, © Jones &■ Bartlett LLC Type Function Amount Description NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION Red blood cells (erythrocytes)

Transport carbon dioxide and oxygen

4.2 million to 6.2 million per microliter

White blood cells (leukocytes)

Destroy parasites and pathogens and remove worn cells

5,000 to 10,000 per microliter

Granulocytes

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Jones Bartlett About© twice the size& of RBCs, with Learning, LLC cytoplasmic granules NOT FOR SALE OR DISTRIBUTION

1. Neutrophils

Phagocytize small particles

54 to 62% of WBCs

Nuclei have 2–5 lobes, granules stain light purple

2. Eosinophils

Help control allergic reactions and inflammation and kill parasites

1 to 3% of WBCs

Bilobed nuclei, granules stain dark red

Jones 3. © Basophils

& Bartlett Learning, LLC Release histamine and heparin NOT FOR SALE OR DISTRIBUTION Agranulocytes

Less than 1% of WBCs

Biconcave discs with no nucleus, about one-third hemoglobin

© Jones &Bilobed Bartlett Learning, nuclei, granules stain blueLLC NOT FOR No SALE OR DISTRIBUTION cytoplasmic granules

1. Monocytes

Phagocytize large particles

3 to 9% of WBCs

2–3 times larger than RBCs, varied nuclei shape

2. Lymphocytes

Provide immunity

25 to 33% of WBCs

Only slightly larger than RBCs, with very large nuclei

© Jones & Bartlett Learning, LLC Platelets Help control blood loss from broken NOT FOR SALE OR DISTRIBUTION (thrombocytes) vessels and begin clotting process

© Jones & Bartlett Learning, LLC Cytoplasmic fragments NOT FOR SALE OR DISTRIBUTION

130,000 to 360,000 per microliter

transported in the plasma from the small intestine to the urea, and uric acid. Blood plasma also contains many elecliver. trolytes, which include potassium, calcium, sodium, mag© Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC In the liver, glucose is stored as glycogen or converted nesium, chloride, phosphate, bicarbonate, and sulfate ions. NOT FOR SALE OR NOT FOR SALE OR DISTRIBUTION to fat. The concentration of glucose in the blood is repreThe most abundant types are sodium and chloride ions. AllDISTRIBUTION sented in milligrams per deciliter (mg/dL). When the blood plasma constituents are regulated so that their blood conconcentration of glucose drops, hypoglycemia (a potentially centrations remain mostly stable. Figure 6–6 summarizes dangerous condition) occurs. When glucose is elevated, it is blood composition. called hyperglycemia, which can lead to diabetes (see Table © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC 6–3). Plasma carries amino acids to the liver to manufacHemostasis FOR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION tureNOT proteins or toSALE be usedOR for energy. Plasma lipids include triglycerides, cholesterol, and phospholipids. Lipids are not The stoppage of bleeding is known as hemostasis. When water-soluble, but plasma is mostly made of water. Hence, blood vessels are damaged, this vital process helps to limit lipids join with proteins to form lipoproteins, which the or prevent blood loss. Hemostasis consists of three phases: plasma can carry. vascular phase, platelet phase, and coagulation phase. When Nonprotein nitrogenous LLC substances have nitrogren atoms, a smaller vesselLearning, is cut or broken, smooth muscles in its © Jones & Bartlett Learning, © Jones & blood Bartlett LLC but are not proteins. In the plasma, these include amino acids, vasospasm ), and loss of blood slows nearly walls contract ( NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION

■■Table 6–3  Blood Glucose Levels

■■Table 6–2  The Plasma Proteins Protein

Origin

Albumins

Liver

Globulins Alpha

Liver

Percentage

Function

Description

Resulting Conditions

Hypoglycemia©

Jones Bartlett Can be& potentially fatal; Learning, LLC symptoms include NOT FOR SALE OR DISTRIBUTION lethargy, impaired mental functioning, irritability, and loss of consciousness

colloid osmotic pressure

36

Transport lipids

fat-soluble © Jones & Bartlett Learning, and LLC vitamins NOT FOR SALE OR DISTRIBUTION ¶Beta Liver Transport lipids Gamma

Level

© Jones of Total& Bartlett Learning, LLC Less than 70 mg/dL NOT60FOR SALE DISTRIBUTION Help OR maintain

and fat-soluble vitamins Constitute a type of antibody

Lymphatic tissues

© Jones & Bartlett LLC Fibrinogen Learning, Liver 4 NOT FOR SALE OR DISTRIBUTION

Plays key role in blood coagulation

Between 70 and Normal © Jones & 110 mg/dL

usually lower BartlettLevels Learning, LLC in the morning and rise after meals NOT FOR SALE OR DISTRIBUTION

Between 110 and 125 mg/dL

Borderline hyperglycemia

126 mg/dL or greater

Hyperglycemia

Does not result in diabetes mellitus

If persistent, can result in diabetes mellitus, © Jones & Bartlett Learning, LLCwhich can cause eye, kidney, and NOT FOR SALE OR DISTRIBUTION nerve damage

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Hemostasis

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Blood

45%

55%

Formed elements

Plasma

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Platelets 4.8%

Red White Electrolytes blood cells blood cells 95.1%

0.1%

Water 92%

Proteins

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Nutrients

Gases

7%

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Hormones

© Jones & Bartlett Learning, LLC Eosinophyls Basophils Monocytes NOT FORNeutrophils SALE OR DISTRIBUTION 54–62%

1–3%

<1%

3–9%

Lymphocytes

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Albumins Globulins Fibrinogen NOT FOR SALE OR

CO2

25–33%

Figure 6–6  Blood composition

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immediately. A vasospasm has the potential to completely Serum close the ends of a severed vessel. Serum is the clear, yellow liquid that remains after a clot The effects of vasospasm may last for a few minutes up forms. It is plasma minus & some, but not all, of the clotting fac© Jones &At Bartlett LLC © Jones Bartlett Learning, LLC to about 30 min. that time,Learning, a platelet plug has formed, tors. Because blood is approximately one-half cells and oneORPlatelets DISTRIBUTION NOT SALE DISTRIBUTION andNOT blood FOR begins SALE coagulating. release serotonin to half liquid, any testFOR requiring 1 mL OR of serum would require contract smooth muscles in blood vessels, reducing blood 2 mL of blood to be collected. loss. Platelets stick to rough surfaces and connective tissue Following the addition of clot activator to most vacuum collagen under the endothelial blood vessel lining. They also tubes, serum for testing needs to clot for only 15 to 20 min stick to one another to form a platelet plug in the area of the before it is centrifuged. Plasma fibrinogen traps red blood vesselLearning, injury. Larger LLC breaks may require a blood clot © Jones & blood Bartlett © Jones Bartlett Learning, LLC and chemistry cells to& form a fibrin network. Immunological to stop bleeding (see Figure 6–7). are SALE performed on DISTRIBUTION serum. A variety of tests can now be NOT FOR SALE OR DISTRIBUTION NOTtests FOR OR The formation of a blood clot is known as coagulation. It performed on either serum or plasma. requires many biochemicals known as clotting factors. Some clotting factors promote coagulation while others inhibit it, Plasma so a delicate balance between these two types is achieved Plasma is the fluid portion of blood that remains all blood to address the specific©injured tissue. The most Learning, important Jones & Bartlett LLC © Jones & after Bartlett Learning, LLC cells have been removed. It consists of water and dissolved event in coagulation is the conversion of the plasma protein FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION proteins, amino acids, glucose,NOT fats, fatty acids, electrolytes, fibrinogen to the insoluble threads of the protein called fibrin. gases, and metabolic wastes. It is composed of about 90% The first step is the release of tissue thromboplastin, which water, 9% protein, and other chemical substances that total results in the production of prothrombin activator. Figure about 1%. Plasma comprises the liquid portion of whole blood 6–8 describes the blood-clotting system. There are two paththat contains active clotting agents. Plasma is used for “stat” ways to the activation of the clotting system. © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC chemistry testing and coagulation studies. Prothrombin is an alpha globulin made in the liver on NOT FOR SALE OR DISTRIBUTION FOR SALE OR DISTRIBUTION A whole NOT blood specimen is centrifuged to separate the a continual basis, and it is always present in the blood various blood components. Red blood cells will settle in the plasma. Prothrombin activator converts prothrombin to bottom of the tube, with the white blood cells and platelets thrombin, which causes fibrinogen to be cut into sections forming a thin, white “buffy coat” and the plasma remainof fibrin. This fibrin then joins to form long threads. The ing above it. At this point, the plasma contains all of the disthreads stick to the surfaces of damaged blood vessels to © Jones & create Bartlett Learning, © Jones BartlettofLearning, LLC the coagulation solved & components the blood, including a mesh that traps LLC blood cells and platelets. The contain an anticoagulant, natural result is OR a blood clot. After the formation of the clot, serum NOT FOR SALE DISTRIBUTION NOTfactors. FOR Plasma SALEspecimens OR DISTRIBUTION heparin, to prevent clotting. remains. © Jones and Bartlett Publishers. NOT FOR SALE OR DISTRIBUTION

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CHAPTER 6  Hematology

© Jones & Bartlett Learning, LLC NOT FOR SALE OR DISTRIBUTION

© Jones & Bartlett Learning, LLC NOT FOR SALE OR DISTRIBUTION

1

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© Jones & Bartlett Learning, LLC NOT FOR SALE OR DISTRIBUTION

2

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© Jones & Bartlett Learning, LLC 3 NOT FOR SALE OR DISTRIBUTION

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4

© Jones & Bartlett Learning, LLC NOT FOR SALE OR DISTRIBUTION 1

Vessel wall break

2

Bleeding starts

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ThrombocytesLLC stick together to seal the area of © theJones breakage & Bartlett Learning, LLC © Jones & Bartlett3 Learning, NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION 4 Thrombocytes form a platelet plug to stop bleeding

Figure 6–7  Platelet plug

© Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC NOT SALE ORitDISTRIBUTION NOT FOR SALE OR DISTRIBUTION continual process can work only for a FOR short time because Appearance of Serum and Plasma interrupts the stability of the body’s internal environment. Blood serum appears as a yellow or straw-colored fluid. It is seen after blood has been allowed to clot, and it does not contain fibrinogen, which is found in the clotted portion of Jones &plasma Bartlett the©blood. Blood is theLearning, pale yellowishLLC liquid part of whole blood. It contains factors that help form NOT FOR SALEcoagulation OR DISTRIBUTION clots to stop bleeding.

Excess thrombin is normally carried away to avoid the formation of a massive blood clot. As a result, blood coagulation usually occurs in blood that is not moving or that is only © Jones & Bartlett Learning, LLC moving slowly. Clotting stops because excess thrombin is FOR SALE OR DISTRIBUTION absorbed onNOT the clot. Blood clots in ruptured vessels are invaded by fibroblasts to produce fibrous connective tissue that helps seal blood vesBlood Clotting sel breaks. Clots that form in tissues as a result of blood leakMore prothrombin activator becomes present if tissue damage (hematomas) disappear over time. This process requires © Jones & age Bartlett Learning, LLC © Jones & Bartlett Learning, LLC is more severe. Continual clotting occurs to stop greater the plasma protein plasminogen to be converted to plasmin, damage. OR Positive feedback is used to stimulate more clotting enzyme that digests threads of fibrin and other proteins NOT FOR SALE DISTRIBUTION NOTanFOR SALE OR DISTRIBUTION action based on the original clotting action. However, this involved in clotting. While plasmin may dissolve entire clots, © Jones and Bartlett Publishers. NOT FOR SALE OR DISTRIBUTION

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Blood Types and Transfusions

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Injured cells in wall NOT FOR of vessel release thromboplastin

1

© Jones & Bartlett Learning, LLC Prothrombin NOT FOR SALE OR DISTRIBUTION activator

(b)

© Jones & Bartlett Learning, LLC NOT FOR SALE OR DISTRIBUTION Fibrin network

2 Prothrombin

Thrombin

© Jones & Bartlett Learning, LLC NOT FOR SALE OR DISTRIBUTION 3

Fibrinogen

© Jones & Bartlett Learning, LLC NOT FOR SALE OR DISTRIBUTION Fibrin 4

RBCs and platelets trapped in fibrin network

© Jones & Bartlett Learning, LLC NOT FOR SALE OR DISTRIBUTION (a)

Platelets release platelet thromboplastin

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5

Figure 6–8  Blood Clotting Simplified. (a) Injured cells in the walls of blood vessels release the chemical thromboplastin (1). Thromboplastin © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC stimulates the conversion of prothrombin, found in the plasma, into thrombin (2). Thrombin, in turn, stimulates the conversion of the plasma NOT FOR SALE OR DISTRIBUTION NOT SALE DISTRIBUTION protein fibrinogen into fibrin (3). The fibrin network captures RBCs and platelets (4). Platelets in theFOR blood clot releaseOR platelet thromboplastin (5), which converts additional plasma prothrombin into thrombin. Thrombin, in turn, stimulates the production of additional fibrin. (b) A scanning electron micrograph of a fibrin clot that has already trapped platelets and RBCs, plugging a leak in a vessel. The RBCs are red, and the fibrin network is turquoise.

© Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC those that fill large blood vessels are usually not removed agglutination. This involves red blood cell surface called SALE NOT FOR SALE OR DISTRIBUTION NOTisFOR OR DISTRIBUTION

naturally. molecules called antigens (agglutinogens) that react with antibodies (agglutinins) from the plasma. There are more A thrombus is a clot that forms abnormally in a vessel. An embolus is a clot that dislodges or fragments to be carthan 260 antigens on RBC membranes. A few of them can ried away in the blood flow. Emboli usually move until they produce serious transfusion reactions, including antigens of reach narrow vessels, © which they may block. When a blood the ABO group and those of the group. & Bartlett Learning, LLC Jones & Bartlett Learning, LLC ©Rh Jones clot forms in a vital organ’s vessels, it kills the tissues served The ABO blood group is based on the presence or lack NOT FOR OR NOT FOR SALE OR DISTRIBUTION (infarction) by the vessel, a potentially fatal occurrence. If this of two major protein antigens (antigen A andSALE antigen B) on DISTRIBUTION occurs in the heart, it is known as coronary thrombosis. If it RBC membranes. Erythrocytes may have one of the followoccurs in the brain, it is known as cerebral thrombosis. ing four antigen combinations: ■■ Antigen A only—type A blood Pulmonary embolism describes a clot blocking a ves■■ Antigen B only—type B blood sel supplying the lungs. In atherosclerosis, the endothelial © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC ■■ Both antigen A and B—type AB blood (the least comlinings of blood vessels change due to fatty deposits that NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION mon type) accumulate. ■■ Neither antigen A nor antigen B—type O blood (the most common type) Blood Types and Transfusions Blood types are inherited. Antibodies related to each type of Blood consists of different types, not all of which are comantigen are produced between 2 and 8 months after birth. For © Jones & patible. Bartlett LLCof whole blood depend on © Jones & Bartlett SafeLearning, blood transfusions example, if antigen ALearning, is absent, theLLC antibody called anti-A matchingOR the blood types of both donors and recipients. The produced. Therefore, people with type A blood (meaning NOT FOR SALE DISTRIBUTION NOTisFOR SALE OR DISTRIBUTION clumping of red blood cells following a transfusion reaction that antigen A is present but antigen B is absent) have anti-B © Jones and Bartlett Publishers. NOT FOR SALE OR DISTRIBUTION

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CHAPTER 6  Hematology Type A blood

Type B blood

© Jones & Bartlett Learning, LLC A antigen B antigen NOT FOR SALE OR DISTRIBUTION

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Anti-B antibody

Anti-A antibody

A antigen

Antibody to type A blood

Antibody to type B blood

B antigen

Red blood cell

© Jones & Bartlett Learning, LLC NOT FOR SALE OR DISTRIBUTION Type AB blood

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Type O blood

Anti-A antibody

A antigen

© Jones & Bartlett Learning, LLC B antigen NOT FOR SALE OR DISTRIBUTION

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Anti-B antibody NOT

Figure 6–9  Various antigens and antibodies distinguish blood types

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■■Table 6–4  ABO Blood Group Antigens and Antibodies

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Antibodies of a certain type will react with antigens of the same type and cause clumping of RBCs, so these combinations must be avoided. For example, a person with type A A Anti-B A (anti-B) blood must not receive blood of either type B or B B Anti-A © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC type AB in order to avoid clumping. A person with type B AB Both A and B Neither anti-A anti-B NOT SALE ORADISTRIBUTION NOT FOR SALE ORnorDISTRIBUTION (anti-A) blood must not receive type AFOR or type AB blood. O Neither A nor B Both anti-A and anti-B person with type O (anti-A and anti-B) must not receive type A, B, or AB blood. Because type AB blood lacks both anti-A and anti-B antibodies, those with type AB blood can receive antibody. The opposite is true for people with type B blood. transfusions from any other type. Because of this, type AB © Jones LLC & Bartlett Learning, LLC Those with type& ABBartlett blood haveLearning, neither of the two antibodies. individuals © areJones called universal recipients. Rapid transfuNOT FOR SALE OR both DISTRIBUTION NOT FOR SALE OR DISTRIBUTION People with type O blood have antibodies (see Figure sion must be avoided, however, because agglutination can 6–9). Anti-A and anti-B antibodies in blood group O individstill occur as a result of certain antibodies in the blood being uals are often IgG class antibodies and may cross the placenta, transfused. It is therefore always best to transfer blood from but usually do not. When they do not cross the placenta, a the same type as the person requiring the transfusion (see pregnant woman and her fetus may have different blood Table 6–5). Note that the permissible donor types listed in and agglutination in the fetal cells cannot occur. Howthis table should be used only in extreme © Jones & types, Bartlett Learning, LLC © Jones & Bartlett Learning, LLCemergencies. Figever, when these antibodies do cross the placenta, the result ure 6–10 illustrates the concept of agglutination. NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION is a mild hemolytic disease of the newborn (HDN) because the Because type O blood lacks antigens A and B, it can be A- and B-antigens are not fully expressed at birth. Table 6–4 transfused, in extreme emergencies, into people with any summarizes blood types, antigens, and antibodies. other type. Because of this, people with type O blood are Blood Type

Antigen Present

Antibody Present

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Anti-B antibody A antigen

© Jones & Bartlett Learning, LLC NOT FOR SALE Red OR blood DISTRIBUTION cell

Anti-A antibody

© Jones & Bartlett Learning, LLC NOT FOR SALE OR DISTRIBUTION Agglutination of red blood cells

© Jones & (a) Bartlett Learning, LLC Figure 6–10  Agglutination NOT FOR SALE OR DISTRIBUTION

(b) © Jones & Bartlett Learning, LLC NOT FOR SALE OR DISTRIBUTION

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Summary

■■Table 6–5  Blood Transfusion Rules

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may be normal, at birth (or miscarriage) the placental mem© Jones & Bartlett Learning, LLC

branes tear, allowing some of the fetus’s Rh-positive RBCs to Permissible Donor NOTenter FOR DISTRIBUTION Type theSALE mother’sOR circulation. This may stimulate her tissues

to begin producing anti-Rh antibodies. If she becomes pregnant a second time and the fetus is Rh-positive, these antiB B O bodies (hemolysins) cross the placental membrane to destroy AB AB A, B, and O the fetal RBCs. The fetus develops hemolytic disease of the Learning, LLC © Jones Bartlett Learning, LLC O O© Jones & Bartlett No alternate types fetus and newborn, formerly referred to as& erythroblastosis NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION fetalis. While extremely rare due to the careful management of Rh status, this condition may cause the death of the fetus or infant. Anemia, an enlarged liver or spleen, generalized swelling, and newborn jaundice are signs of this condition. called universal donors. Type O blood still should be given © Jones &blood Bartlett Learning, © Jones & Bartlett Learning, LLC to people of other types slowly so that itLLC will be diluted Summary by the recipient’s volume. This will minimize chances NOT FOR blood SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION Blood is a type of connective tissue. It consists of red blood of an adverse reaction. cells, white blood cells, and platelets suspended in a liquid, The Rh blood group received its name from the rhesus plasma, extracellular matrix. Blood transports substances monkey because it was in this type of monkey that it was first between body cells and the external environment. It helps to studied. There are several Rh antigens (factors) in humans, maintain a stable internal environment. the most prevalent of which is antigen D. If it is present on © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLCBlood is separated into formed elements and liquid portions. Red blood cells the RBC membranes, the blood is called Rh-positive. If not, it NOT FOR SALE OR DISTRIBUTION NOTcarry FOR SALE OR DISTRIBUTION oxygen to the body tissues. White blood cells are imporis called Rh-negative. Only 15% of the U.S. population is Rhtant in protecting the body against pathogens and infection. negative. The presence or absence of Rh antigen is inherited, Platelets are vital for blood coagulation. but the antibodies that react with it (called Rh antibodies) Blood plasma transports gases and nutrients, helps mainare not spontaneous. They form only in Rh-negative people tain stable pH, and helps regulate the fluid and electrolyte because of specific stimulation. © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC balance. Hemostasis is the stoppage of bleeding. It involves An Rh-negative person receiving Rh-positive blood will FOR SALE OR NOT FOR SALE OR DISTRIBUTION the steps of blood vessel spasm,NOT platelet plug formation, andDISTRIBUTION begin producing anti-Rh antibodies (see Figure 6–11). The blood coagulation. Blood can be typed on the basis of cell first transfusion usually causes no serious problems. But after surface antigens. The ABO blood group concerns the presthat, the Rh-negative person has become sensitized to Rhence or absence of antigens A and B. The Rh blood group positive blood. A second transfusion, even months later, will concerns the Rh antigen, which is present on the red blood usually cause the donated RBCs to agglutinate. © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC cell membranes of Rh-positive blood but is not present in A similar condition can occur when an Rh-negative female Rh-negativeNOT blood. FOR SALE OR DISTRIBUTION NOT FOR ORfetus. DISTRIBUTION is pregnant with anSALE Rh-positive Although the pregnancy A

A

O

© Jones & Bartlett(a)Learning, LLC NOT FOR SALE OR DISTRIBUTION Child is Rh positive

(b)

Fetal red blood © cellsJones Mother& makes anti-Rh Learning, Antibodies Bartlett LLCenter fetal enter the mother’s antibodies that attack blood stream where they FOR bloodstream NOT fetal red SALE blood cellsOR DISTRIBUTION attack Rh+ red blood cells

Rh+ red blood cells

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© Jones & Bartlett Learning, LLC Figure 6–11  The Rh factor and pregnancy NOT FOR SALE OR DISTRIBUTION

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CHAPTER 6  Hematology

CRITICAL THINKING eosinophils © Jones C. & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC D. basophils An instructor was conducting an oral examination, and he NOT FOR SALEareOR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION 6. Platelets formed from cells in the bone marrow asked a phlebotomist the following questions. How would

known as you respond to each of these? A. megakaryocytes 1. Why is venipuncture a common technique for obtainB. erythroblasts ing a blood sample? C. lymphoblasts 2. How would the© hematocrit after anLearning, individual Jones change & Bartlett LLC D. myeloblasts © Jones & Bartlett Learning, LLC suffered a significant blood loss? NOT FOR SALE OR NOT FOR SALE OR DISTRIBUTION 7. Which of the following vitamins is needed for the for-DISTRIBUTION 3. How do basophils respond during inflammation? mation of clotting factors? 4. Which blood type or types can be transfused into a A. vitamin A person with type O blood? B. vitamin D C. vitamin K WEBSITES © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC D. vitamin E 8. Thrombocytes are SALE OR DISTRIBUTION http://surgery.about.com/od/beforesurgery/qt NOT FOR SALE OR DISTRIBUTION NOT FOR A. small cells that lack a nucleus /PTPTTINRtests.htm B. small cells with many-lobed nuclei http://www.hematology.org/ C. fragments of large megakaryocytes http://www.mhhe.com/biosci/esp/2002_general/Esp/folder D. large cells with prominent nuclei _structure/tr/m1/s7/trm1s7_3.htm 9. of the following whiteLLC blood cells release his© Jones & Bartlett Learning, LLC © Jones Which & Bartlett Learning, http://www.nhlbi.nih.gov/health/dci/Diseases/bt/bt tamine and heparin? NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION _whatis.html A. basophils B. monocytes http://www.purchon.com/biology/plasma.htm C. neutrophils http://www.redcrossblood.org/learn-about-blood/bloodD. eosinophils types 10. Erythrocytes are formed in © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC http://www.unomaha.edu/hpa/blood.html A. the spleen NOT FOR SALE OR DISTRIBUTION B. red bone marrow NOT FOR SALE OR DISTRIBUTION REVIEW QUESTIONS C. yellow bone marrow D. the liver 11. Which of the following hormones regulates producMultiple Choice tion of red blood cells? 1. Which of & theBartlett following Learning, terms means “the process of © Jones LLC © Jones & Bartlett Learning, LLC A. erythropoietin red blood cell production”? NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION B. thymosin A. erythropoiesis C. epinephrine B. erythrocytosis D. somatotropin C. erythropenia 12. Which of the following is the major protein in a red D. hemocytosis blood cell? 2. Immature red blood cells are found in peripheral blood A. myoglobin Learning, LLC © Jones & Bartlett Learning, LLC © Jones & Bartlett samples and are referred to as B. fibrinogen NOT FOR SALEA. OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION myeloblasts C. albumin B. erythroblasts D. hemoglobin C. reticulocytes 13. Older erythrocytes are broken down by the D. erythrocytes A. kidneys 3. The formed elements of the blood are called © Jones & Bartlett Learning, LLC B. lungs © Jones & Bartlett Learning, LLC A. clotting proteins C. spleen B. lipoproteinsNOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION D. pancreas C. albumins 14. Allergies stimulate an increased __________ count. D. blood cells A. erythrocyte 4. Which of the following are the most abundant proteins B. eosinophil in blood plasma? C. monocyte A. fibrinogens © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC D. neutrophil B. albumins NOT FOR SALE OR DISTRIBUTION NOT FOR OR DISTRIBUTION 15. People of which of SALE the following blood groups are C. lipoproteins known as universal recipients? D. globulins A. group O 5. Which of the following white blood cells produce B. group A antibodies? C. group B A. monocytes © Jones & Bartlett Learning, LLC © Jones D. & Bartlett group AB Learning, LLC B. lymphocytes

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