Module 9: Disorders of Red Blood Cells and Hemostasis

Vocabulary flashcards covering red blood cell disorders, hemostasis mechanics, various types of anemia, and polycythemia etiologies.

Hypercoagulation

An abnormal increase in blood clotting that raises the risk of thrombosis and blood vessel blockage, occurring when platelets or clotting factors become overly active.

Polycythemia Vera

A myeloproliferative disorder where the bone marrow produces excessive red blood cells and platelets, thickening the blood and increasing the likelihood of clot formation.

Thrombosis

The formation of blood clots inside blood vessels which can obstruct blood flow and lead to tissue ischemia, tissue death, stroke, or heart attack.

Thrombocythemia

A condition characterized by an increased platelet count, which can serve as an etiology for hypercoagulation.

Anticoagulants

Medications such as heparin and warfarin that prevent new clots from forming and stop existing clots from growing larger, but do not dissolve present clots.

Clot Resolvers (Thrombolytics)

Agents like streptokinase and recombinant tissue plasminogen activator (rTPA) that dissolve existing clots by converting plasminogen into plasmin to break down fibrin.

Hypocoagulation

A disorder characterized by decreased blood clotting, resulting in an increased risk of bleeding and hemorrhage.

Thrombocytopenia

A condition defined by a platelet count below $100,000/\text{μ L}$, which reduces the body's ability to form platelet plugs.

Immune or Idiopathic Thrombocytopenic Purpura (ITP)

An autoimmune disorder in which antibodies attack platelets, causing their destruction in the spleen; manifested by bruising, petechiae, and purpura.

Disseminated Intravascular Coagulation (DIC)

A condition beginning with uncontrolled thrombin production causing widespread clotting, followed by the depletion of platelets and factors leading to severe bleeding.

Hemorrhagic Anemia

Anemia caused by blood loss from factors such as trauma, ulcers, cancer, or menstruation, treated via blood transfusions and fluid replacement.

Hemolytic Anemia

Anemia resulting from the premature destruction of red blood cells, with examples including Sickle cell disease and thalassemia.

Iron Deficiency Anemia

Anemia caused by inadequate iron, characterized by microcytic and hypochromic red blood cells.

Aplastic Anemia

Anemia due to bone marrow failure or suppression, often caused by chemotherapy, radiation, or toxins.

Relative Polycythemia

A type of polycythemia caused by dehydration, for which the treatment is fluid replacement.

Secondary Polycythemia

Increased red blood cell production triggered by increased EPO levels due to chronic hypoxia, smoking, or lung and heart disease.

Sickle Cell Disease

An inherited autosomal recessive disorder where abnormal hemoglobin causes red blood cells to sickle in low oxygen levels, blocking blood vessels.

Newborn Hemolytic Disease (Erythroblastosis Fetalis)

A condition where an Rh-negative mother's antibodies cross the placenta and destroy the red blood cells of an Rh-positive fetus.

Pernicious Anemia

A specific type of nutritional deficiency anemia caused by a lack of intrinsic factor leading to Vitamin B12 deficiency.

Megaloblastic Anemia

Anemia developing from chronic deficiencies of folic acid or Vitamin B12, causing red blood cells to become abnormally large (macrocytic) and immature.

Erythropoietin (EPO)

The hormone normally produced by the kidneys that stimulates red blood cell production in the bone marrow.

Splenomegaly

An enlarged spleen that can trap and destroy excessive numbers of red blood cells and platelets, contributing to anemia and thrombocytopenia.

What is a blood clot?

A blood clot is a mass of blood that has changed from a liquid to a gel, preventing excessive bleeding during injuries.

What causes thrombocytopenia?

Thrombocytopenia can be caused by various factors including bone marrow disorders, autoimmune diseases, and certain medications.

What is the role of Erythropoietin (EPO)?

EPO stimulates the production of red blood cells in the bone marrow, primarily in response to low oxygen levels.

What are common symptoms of hemolytic anemia?

Symptoms of hemolytic anemia may include fatigue, pallor, jaundice, and dark urine due to red blood cell breakdown.

How is pernicious anemia treated?

Pernicious anemia is typically treated with vitamin B12 injections or oral supplements to counteract the deficiency.

What is the difference between primary and secondary polycythemia?

Primary polycythemia is due to a bone marrow disorder, while secondary polycythemia occurs from increased erythropoietin due to hypoxia or other conditions.

What can lead to disseminated intravascular coagulation (DIC)?

DIC can be triggered by severe infections, trauma, or complications in pregnancy, leading to widespread clotting and bleeding.

What is the significance of splenomegaly in blood disorders?

Splenomegaly can indicate underlying conditions like hematologic diseases, as it can trap and destroy blood cells.