Erythrocyte Disorders Anemia – blood has abnormally low oxygen-carrying capacity It is a symptom rather than a disease itself Blood oxygen levels cannot support normal metabolism Signs/symptoms include fatigue, paleness, shortness of breath, and chills

Anemia: Insufficient Erythrocytes Hemorrhagic anemia – result of acute or chronic loss of blood Hemolytic anemia – prematurely ruptured RBCs due to overactive spleen or infection Aplastic anemia – destruction or inhibition of red bone marrow

Anemia: Decreased Hemoglobin Content Iron-deficiency anemia results from: Inadequate intake of iron-containing foods Megaloblastic Anemia: RBCs are abnormally large Usually results from lack of folic acid or vitamin B12 Pernicious anemia results from: Deficiency of vitamin B12 Lack of intrinsic factor needed for absorption of B12 Intrinsic factor is a gastric juice secretion Treatment is intramuscular injection of B12 application of Nascobal

Anemia: Abnormal Hemoglobin Thalassemias – absent or faulty globin chain in Hb RBCs are thin, delicate, and deficient in Hb Sickle-cell anemia – results from a defective gene coding for an abnormal Hb called hemoglobin S (HbS) HbS has a single amino acid substitution in the beta chain This defect causes RBCs to become sickle-shaped in low oxygen situations

Myelodysplastic Syndrome Used to be called pre-leukemia Group of bone marrow disorders characterized by: Insufficient production of one or more types of blood cells Due to dysfunction of bone marrow

Leukocytes Disorders: Leukemias Leukemia refers to cancerous conditions involving WBCs Leukemias are named according to the abnormal WBCs involved Myelocytic leukemia – involves red marrow Lymphocytic leukemia – involves lymphocytes

Leukemia Immature WBCs are found in the bloodstream in all leukemias Bone marrow becomes totally occupied with cancerous leukocytes The WBCs produced, though numerous, are not functional Death is caused by internal hemorrhage and overwhelming infections Treatments include irradiation, antileukemic drugs, and bone marrow transplants

Hemostasis Disorders: Bleeding Disorders Inability to synthesize procoagulants by the liver results in severe bleeding disorders Causes can range from vitamin K deficiency to hepatitis and cirrhosis Inability to absorb fat can lead to vitamin K deficiencies as it is a fat-soluble substance and is absorbed along with fat Liver disease can also prevent the liver from producing bile, which is required for fat and vitamin K absorption

Hemostasis Disorders: Bleeding Disorders Hemophilias – hereditary bleeding disorders caused by lack of clotting factors Hemophilia A – most common type (83% of all cases) due to a deficiency of factor VIII Hemophilia B – due to a deficiency of factor IX Hemophilia C – mild type, due to a deficiency of factor XI

Hemostasis Disorders: Bleeding Disorders Symptoms and signs include prolonged bleeding and painful and disabled joints Treatment is with blood transfusions and the injection of missing factors

Synovitis due to hemophilia

Hemostasis Disorders Von Willebrand Disease: shortage of von Willebrand factorplasma component that helps platelets stick to damaged tissue & carries clotting factor VIII. Hereditary Easy bruising Decreased adherence to vascular injury Inadequate patelet plug lengthens bleeding time

Hemostasis Disorders: Bleeding Disorders Thrombocytopenia – condition where the number of circulating platelets is deficient Patients show petechiae (red/purple dots on skin) due to spontaneous, widespread hemorrhage Caused by suppression or destruction of bone marrow (e.g., malignancy, radiation) Can also be drug induced Treated with whole blood transfusions

Hemostasis Disorders Disseminated Intravascular Coagulation (DIC): widespread clotting in intact (uninjured) blood vessels Left over blood cannot clot Blockage of blood flow and severe bleeding follows Most common as: A complication of pregnancy A result of septicemia or incompatible blood transfusions

Hemostasis Disorders: Thromboembolytic Conditions Thrombus – a clot that develops and persists in an unbroken blood vessel Thrombi can block circulation, resulting in tissue death Coronary thrombosis – thrombus in blood vessel of the heart Deep Vein Thrombosis (DVT)—thrombus attached to wall of deep vein. Thrombotic Occlusion: blocking of artery by thrombus

Hemostasis Disorders: Thromboembolytic Conditions Embolus – a thrombus or foreign object freely floating in the blood stream Pulmonary emboli can impair the ability of the body to obtain oxygen Cerebral emboli can cause strokes Embolism—blockage caused by embolus Air or fat or blood clot

Prevention of Undesirable Clots Substances used to prevent undesirable clots: Aspirin – an antiprostaglandin that inhibits thromboxane A2 Heparin – an anticoagulant used clinically for pre- and postoperative cardiac care; also found naturally in the body Warfarin (Coumadin) – used for those prone to atrial fibrillation

Blood Disorders Blood dyscrasia: any pathologic condition of cellular elements of the blood Hemochromatosis (Iron overload disease): genetic disorder Instestines absorbs too much iron Causes damage in organs where iron is accumulated

Blood Disorders Polycythemia: abnormal increase in number of RBCs; red bone marrow excessively producing RBCs Polycythemia vera: condition developed in people living in high altitudes Leukocytosis: WBC count is higher than normal. (>10,000 microliters) Usually due to bacterial infection Leukopenia: total number of leukocytes is less than normal (<5,000 mcL) Septicemia: Blood poisoning Systemic condition caused by spread of microorganisms and their toxins via circulating blood Thrombocytosis: abnormal increase in number of platelets in circulating blood Hemorrhage: loss of a large amount of blood in a short time Transfusion Reaction: complication of blood transfusion in which blood of patient and donor does not match Coagulation occurs

Hemolytic Disease of the Newborn (HDN) Hemolytic disease of the newborn – Rh+ antibodies of a sensitized Rh– mother cross the placenta and attack and destroy the RBCs of an Rh+ baby Rh– mother becomes sensitized when exposure to Rh+ blood causes her body to synthesize Rh+ antibodies

Hemolytic Disease of the Newborn The drug RhoGAM can prevent the Rh– mother from becoming sensitized Treatment of hemolytic disease of the newborn involves pre-birth transfusions and exchange transfusions after birth