10.9 Glossary

Anemia (ā-NĒ-mē-ă): A blood disorder characterized by a deficiency of red blood cells and/or hemoglobin, leading to decreased oxygen delivery to body tissues and symptoms like fatigue, weakness, shortness of breath, and pale skin. (Chapter 10.6)

Anticoagulant (ăn-tī-kō-AG-yū-lănt): A substance or medication that prevents or reduces coagulation of blood, thereby prolonging the clotting time. (Chapter 10.5)

Apheresis (ăf-ĕ-RĒ-sĭs): A procedure where a specific component of blood is removed from a donor, and the remaining components are returned to the donor. (Chapter 10.7)

Aplastic anemia (ā-PLAS-tĭk ā-NĒ-mē-ă): A bone marrow condition causing insufficient production of red blood cells. (Chapter 10.6)

Basophils (bā-sō-fĭls): The least common type of white blood cell, playing a role in inflammatory responses, particularly those involving allergic reactions. (Chapter 10.4)

Bilirubin (bĭl-ĭ-rōō-bĭn): A yellow compound that occurs in the normal catabolic pathway that breaks down heme in vertebrates. High levels in the bloodstream can lead to jaundice. (Chapter 10.4)

Blood product (blŭd prah-DUHKT): Components of blood, such as red blood cells, white blood cells, platelets, and plasma, used for transfusions. (Chapter 10.7)

Blood transfusion (blŭd tran-SFŪ-zhŏn): A procedure that enables the transfer of blood products from one person to another. (Chapter 10.4)

Bone marrow (bōn MAR-ō): The soft, spongy tissue found inside bones, responsible for the production of blood cells. (Chapter 10.4)

Bone marrow aspiration (BŌn MĂR-rōw ă-spĭ-RĀ-shŏn): The extraction of a small sample of liquid bone marrow for laboratory analysis to diagnose severe blood disorders like leukemia. (Chapter 10.7)

Bone marrow biopsy (BŌn MĂR-rōw BĪ-ŏp-sē): Obtaining a core of bone and marrow tissue for examining the bone marrow space, often performed with bone marrow aspiration. (Chapter 10.7)

Bone marrow transplant (BŌn MĂR-rōw TRĂNS-plănt): A treatment for severe hematological diseases or cancers like leukemia, involving the replacement of a patient’s bone marrow with healthy stem cells from a donor. (Chapter 10.7)

CBC with differential (CBC wĭth Dĭf-ĕ-REN-shăl): A CBC test that includes an additional measurement of the different types of white blood cells, such as neutrophils, lymphocytes, monocytes, eosinophils, and basophils. (Chapter 10.7)

Coagulation (kō-ag-yū-LĀ-shŏn): The process of blood clotting, an essential part of hemostasis, involving the transformation of blood from a liquid to a gel to stop bleeding. (Chapter 10.5)

Complete blood count (kŏm-PLĒT BLŬD kownt) (CBC): A blood test that provides a comprehensive assessment of various blood components, including red and white blood cells, platelets, hematocrit, and hemoglobin. (Chapter 10.7)

Contusion (kon-TU-zhun): A bruise that occurs when small veins and capillaries under the skin break, releasing blood into the surrounding tissue. (Chapter 10.6)

Embolism (ĒM-bŏ-lĭzm): A condition where an embolus becomes trapped in a blood vessel, potentially causing a heart attack, stroke, or pulmonary embolism. (Chapter 10.6)

Embolus (ĒM-bŏ-lŭs): A piece of a thrombus that has broken free and travels through the bloodstream, potentially causing blockage in blood vessels of major organs. (Chapter 10.6)

Eosinophils (ē-ō-sĭn-ō-fĭls): White blood cells involved in the response to allergic reactions, asthma, and infection with parasites. (Chapter 10.4)

Erythrocytes (ĕ-rĭth-rō-sīts): Red blood cells, which are responsible for carrying oxygen from the lungs to the body’s tissues and carbon dioxide as a waste product, away from the tissues and back to the lungs. (Chapter 10.4)

Erythropoietin (ĕ-rĭth-rō-poi-Ē-tĭn) (EPO): A hormone produced by the kidneys that promotes the formation of red blood cells by the bone marrow. (Chapter 10.4)

Fibrin (FĪ-brin): A fibrous protein formed during blood clotting, essential for the formation of a stable blood clot. (Chapter 10.5)

Fibrinolysis (fī-brĭ-NŌL-ĭ-sĭs): The process that breaks down fibrin in blood clots, playing a crucial role in preventing blood clots from growing and becoming problematic. (Chapter 10.5)

Hematocrit (hē-măt-ō-krĭt) (HCT): A blood test that measures the percentage of the volume of whole blood that is made up of red blood cells. (Chapter 10.4)

Hematologist (hē-mā-TŌL-ō-jist): A physician who specializes in the diagnosis and treatment of blood disorders. (Chapter 10.7)

Hematology (hēm-ă-TŎL-ō-jē): The study of blood, blood components, and blood-forming organs, focusing on their role in health and disease. (Chapter 10.1)

Hematoma (hēm-ă-TŌ-mă): A collection or pooling of blood outside the blood vessel caused by an injury. (Chapter 10.6)

Hemoglobin (hē-mō-glō-bĭn) (Hgb): A protein in red blood cells that carries oxygen from the lungs to the rest of the body and returns carbon dioxide from the body to the lungs. (Chapter 10.4)

Hemolysis (hē-MOL-ĭ-sĭs): The destruction or breakdown of red blood cells, leading to the release of hemoglobin into the surrounding fluid. (Chapter 10.4)

Hemolytic disease of the newborn (hē-mō-LĬT-ik dĭ-zēz əv thə NŪ-bôrn): A condition occurring when an Rh-negative mother’s immune system attacks Rh positive fetal red blood cells, potentially leading to fetal death without treatment. (Chapter 10.4)

Hemophilia (hē-mō-FĒL-ē-ă): A genetic disorder in which blood doesn’t clot normally due to deficient or abnormal clotting factors. (Chapter 10.6)

Hemorrhage (HEM-ŏ-rāj): Excessive bleeding that cannot be controlled by hemostasis and is considered a medical emergency. (Chapter 10.4, Chapter 10.6)

Hemostasis (hē-mō-STĀ-sĭs): The process of blood clot formation at the site of vessel injury. It involves three steps: vascular spasm, formation of a platelet plug, and blood clotting (coagulation). (Chapter 10.4, Chapter 10.5)

Hepatomegaly (hep-ăt-ō-MĔG-ă-lē): Enlargement of the liver, which can be caused by liver disease, cancer, and excess alcohol intake. (Chapter 10.4)

International normalized ratio (ĭn-tĕr-NASH-ŭ-năl NÔR-mă-līzd RĀ-shiō) (INR): A calculation based on the PT used to ensure test results from different labs are comparable; it’s particularly important for patients on anticoagulant medication like warfarin. (Chapter 10.5)

Iron deficiency anemia (īrŏn dē-FĬ-shĕn-sē ā-NĒ-mē-ă): The most common type of anemia, caused by a lack of dietary iron needed for sufficient production of hemoglobin. (Chapter 10.6)

Jaundice (JAWN-dis): A yellowish discoloration of the skin and eyes, usually caused by impaired liver function that affects the metabolism of bilirubin. (Chapter 10.4)

Leukemia (lū-KĒM-ē-ă): Cancer of the bone marrow and the body’s blood-forming tissues, characterized by an abundance of nonfunctional leukocytes (white blood cells). (Chapter 10.6)

Leukocytes (lū-kō-sīts): White blood cells, which are part of the immune system and help the body to fight infection and other diseases. (Chapter 10.4)

Leukocytosis (lū-kō-sī-TŌ-sĭs): Excessive leukocyte (white blood cell) production, often with nonfunctional cells, leading to increased risk of infection. (Chapter 10.6)

Leukopenia (lū-kō-PĒN-ē-ă): A condition where too few leukocytes (white blood cells) are produced, impacting the individual’s ability to fight off disease. (Chapter 10.6)

Liver (LIV-ĕr): A vital organ that plays multiple roles in digestion, metabolism, and hemostasis, including the production of bile and the storage of blood and blood cells. (Chapter 10.4)

Lymphocytes (lĭm-fō-sīts): A subtype of white blood cells found in the lymphatic system, playing a large role in the immune response. (Chapter 10.4)

Lymphoma (lim-FŌ-mă): A type of cancer where masses of malignant lymphocytes (white blood cells) collect in lymph nodes, the spleen, the liver, and other tissues. (Chapter 10.6)

Medical laboratory assistants (mĕd-ĭ-căl LĂB-ŏr-ă-tŏr-ē ă-Sĭs-tănts) (MLA): Professionals who assist in preparing, testing, and processing specimen samples. (Chapter 10.7)

Medical laboratory scientists (mĕd-ĭ-căl LĂB-ŏr-ă-tŏr-ē Sĭ-ĔN-tĭsts) (MLS): Professionals who perform complex analyses of tissue, blood, and other body fluids. (Chapter 10.7)

Medical technologist (mĕd-ĭ-căl Tĕk-nŏl-ŏ-jist) (MT): A medical professional who tests and analyzes blood, other body fluids, and tissue samples. (Chapter 10.7)

Megaloblastic anemia (mĕ-gŭh-lō-plă-stĭk ā-NĒ-mē-ă): Involves a deficiency of vitamin B12 and/or folate, often due to inadequate dietary intake. (Chapter 10.6)

Monocytes (mŏn-ō-sīts): A type of white blood cell that engulfs and digests cellular debris, foreign substances, microbes, and cancer cells. (Chapter 10.4)

Neutrophils (nū-trō-fĭls): A type of white blood cell that helps heal damaged tissues and resolve infections. (Chapter 10.4)

Pancytopenia (păn-sī-tō-PĒ-nē-ă): A reduction of all types of blood components including red and white blood cells, and platelets. (Chapter 10.6)

Partial thromboplastin time (pär-shăl thrŏm-bō-PLAS-tĭn tīm) (PTT): A blood test that measures a specific group of clotting factors and is used to diagnose clotting disorders or monitor patients on anticoagulants. (Chapter 10.5)

Pernicious anemia (pĕr-nĭsh-ē-ŭs ā-NĒ-mē-ă): Caused by poor absorption of vitamin B12 in the gastrointestinal tract. (Chapter 10.6)

Phlebotomist (flĕ-BOT-ŏ-mist): A medical professional trained to withdraw blood or perform blood transfusions.  (Chapter 10.7)

Phlebotomy (flĕ-BOT-ŏ-mē): The practice of drawing blood from a vein, typically for laboratory testing or blood donation. (Chapter 10.4)

Plasma (plăz-mă): The liquid component of blood in which the blood cells and other components are suspended. It plays a vital role in maintaining blood pressure and regulating body temperature. (Chapter 10.4)

Platelets (PLĀT-lĭts): Also known as thrombocytes, these are small, colorless cell fragments in the blood whose main function is to react to bleeding from blood vessel injury by clumping, thereby initiating a blood clot. (Chapter 10.4)

Polycythemia (pol-ē-sī-THĒM-ē-ă): Refers to an elevated red blood cell count, which can be a normal response to living at high altitudes. (Chapter 10.6)

Polycythemia vera (pol-ē-sī-THĒM-ē-ă vee-ruh): A bone marrow disease causing excessive production of immature red blood cells and other blood components, increasing blood viscosity. (Chapter 10.6)

Prothrombin time (PRŌ-thrŏm-bĭn tīm) (PT): A blood test that measures how long it takes blood to clot, used to check for bleeding problems or the effects of anticoagulants. (Chapter 10.5)

Red blood cells (rĕd blŭd sĕls) (RBCs): Cells in the blood that carry oxygen from the lungs to the rest of the body and return carbon dioxide from the body to the lungs for exhalation. (Chapter 10.4)

Rh factor (Ār āch FAK-tŏr): An antigen found on red blood cells; individuals can be Rh positive (Rh+) if they have the antigen or Rh negative (Rh−) if they lack it. (Chapter 10.4)

Rh negative (Ār-āch NĔG-ă-tĭv) (Rh−): Individuals who lack the Rh factor antigen on their red blood cells. (Chapter 10.4)

RhoGAM (RŌ-găm): A medication administered to Rh negative mothers during pregnancy and after birth to prevent the development of Rh antibodies, thereby averting hemolytic disease of the newborn in Rh positive fetuses. (Chapter 10.4)

Rh positive (Ār-āch PŌZ-ĭ-tĭv) (Rh+): Individuals who have the Rh factor antigen present on their red blood cells. (Chapter 10.4)

Sickle cell anemia (SĬK-l sĕl ā-NĒ-mē-ă): A genetic disorder that causes red blood cells to assume a sickle shape, which can block blood flow and cause serious problems in organs throughout the body. (Chapter 10.6)

Spleen (splēn): An organ that serves as a storage site for red blood cells (RBCs) and platelets, filters antigens, and plays a role in the destruction of old RBCs and the breakdown of hemoglobin. (Chapter 10.4)

Splenectomy (splĕ-NEK-tŏ-mē): Surgical removal of the spleen, which can lead to reduced immune function and an increased risk of infection. (Chapter 10.4)

Splenomegaly (splē-nō-MĔG-ă-lē): Enlargement of the spleen, which can occur due to various reasons such as systemic infection, sickle cell disease, or cancer. (Chapter 10.4)

Stem cell transplant (STĔM Sĕl TRĂNS-plănt): Another term for bone marrow transplant, involving the replacement of diseased bone marrow with healthy stem cells. (Chapter 10.7)

Thalassemia (thal-ă- SĒM-ē-ă): An inherited condition typically occurring in individuals from specific regions, characterized by abnormal maturation of red blood cells. (Chapter 10.6)

Thrombocytes (thrŏm-bō-sītz): Also known as platelets, these are blood cells responsible for blood clotting. (Chapter 10.4)

Thrombocytopenia (thrŏm-bō-sī-tō-PĒ-nē-ă): A condition where there is an insufficient number of platelets, leading to ineffective blood clotting and potential for excessive bleeding. (Chapter 10.6)

Thrombocytosis (thrŏm-bō-sī-TŌ-sĭs): A condition characterized by an abnormally high number of platelets in the blood, which can lead to thrombosis. (Chapter 10.6)

Thrombolysis (thrŏm-BŎL-ĭ-sĭs): The process of dissolving a blood clot, often achieved with medications like tissue plasminogen activator (tPA). (Chapter 10.6)

Thrombosis (thrŏm-BŌ-sĭs): The formation of a thrombus, a blood clot, within a blood vessel, potentially causing obstruction of blood flow. (Chapter 10.6)

Thrombus (THROM-bŭs): A blood clot composed of platelets, red and white blood cells, and fibrin strands, potentially leading to decreased blood flow or life-threatening obstruction in blood vessels. (Chapter 10.6)

Viscosity (vĭs-KOS-ĭ-tē): Refers to the state of being thick, sticky, and easily coagulable, as seen in conditions like polycythemia vera. (Chapter 10.6)

White blood cells (wīt blŭd sĕls) (WBCs): Cells of the immune system involved in protecting the body against both infectious disease and foreign invaders. (Chapter 10.4)