HLTH 335 1st Edition Lecture 10Chapter 7: Disease of the BloodToday’s Objective:-Review the cellular components (formed elements) of blood and their functions.-Discuss the etiology, signs and symptoms, diagnostic tests, and treatment of selected diseases of the blood.-Various types of Anemia-Polycythemia Vera-Disorders of Hemostasis-Disorders of White Blood CellsBlood:-Average adult has about 5 liters of blood.-Circulates through body within vessels of cardiovascular system.-A mixture of plasma with cells -Formed elements-Erythrocytes-Leukocytes-PlateletsPlasma:-Composes 55% of blood.-90-92% of plasma is water.-Remainder is dissolved substances.-Plasma proteins-Albumin: helps transport fatty substances.-Globulin: 3 types.-Fibrinogen: blood clotting protein.Erythrocytes:-Hemoglobin (Hgb, Hb) gives red color-Globulin protein + heme molecule-Heme binds to oxygen in the lungs- ~ 5 million RBC per cubic millimeter of blood-Average adult has 35 trillion; more in males than females.-Life span of 120 days-RBC’s bring oxygen to body tissues.These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.Essential Nutrients for Red Blood Cell Synthesis:-Iron-Folic acid-Vitamin B12Nutrient deficiencies, the presence of immature red blood cells, as well as the characteristic color and volume of red blood cells, are laboratory variables that are used to distinguish among different types of anemia.Anemia:-Conditions that decrease red blood cells.-Hemorrhages, excessive destruction, or impaired synthesis. -Symptoms are due to tissue hypoxia (lack of oxygen). -Pallor or lack of color, fatigue, dizziness, headaches, decreased exercise tolerance, rapid heartbeat, and shortness of breath.-Untreated anemia may progress to death from heart failure or cardiovascular collapse or shock.Iron Deficiency Anemia:-Most common cause of anemia worldwide.-Etiology –-increased iron requirements (e.g., pregnancy, adolescent growth spurts).-impaired iron absorption-Hemorrhaging-Without enough iron, the body fails to synthesize hemoglobin, and the ability to transport oxygen is reduced.Risks for Iron Deficiency Anemia:-Sudden growth spurt in adolescent boys may significantly increase physiological demands for iron resulting in iron deficiency anemia.-Adolescent girls may become iron deficient due to inadequate dietary iron, increased growth requirements, and the onset of menstruation. -Supplemental iron is needed during pregnancy as iron is provided to the developing fetus.-Decreases in iron absorption occur with malabsorption syndromes and chronic disease. -Iron absorption requires an intact gastrointestinal tract with healthy intestinal mucosal cells. -Chronic disease, removal of the stomach, and bowel disorders limit availability of iron required for the synthesis of hemoglobin.Symptoms and Diagnosis of Iron Deficiency Anemia:-Symptoms specific to iron deficiency:-craving for ice-swelling of the tongue-dry lips. -Diagnosis of iron deficiency anemia is confirmed by microscopic examination of the blood. -Reduction in red blood cells is called hypochromia.Treatment of Iron Deficiency Anemia:-Identify and correct any causes of bleeding -Oral supplements are effective in those with an intact gastrointestinal tract. -The addition of vitamin C enhances iron absorption. -Injectable iron supplements are available for individuals with malabsorption or those who cannot tolerate oral supplementation.Anemia of Chronic Disease:-The second leading cause of anemia worldwide.-Chronic diseases such as heart disease, cancer, arthritis, as well as chronic infectious disease, induce imflammatory changes that…-suppress red blood cell synthesis in the bone marrow, and-shorten survival of red blood cells already within the systemic circulation.-Anemia of chronic disease may resolve if underlying disease is treated.Vitamin B12 Deficiency Anemia (a.k.a. Pernicious Anemia):-Caused by-inadequate absorption or intake of vitamin B12.-Or a deficiency in a specific protein called intrinsic factor.-instrinsic factor is produced in the stomach and is essential for the absorption of vitamin B12 from the small intestine.-Without vitamin B12 and intrinsic factor, the membranes of immature red blood cells rupture easily within the chemical environment of the blood stream.-The result is fewer than normal red blood cells, and consequently a reduce oxygen carrying capacity.Etiology of Pernicious Anemia:-Etiology-Inadequate diet, absorption, or utilization of B12.-Increased requirements and increased excretion of vitamin B12.-Strict vegetarianism.-Abnormal bacterial growth in the small intestine (impair absorption or enhance elimination of vitamin B12).-Removal of the stomach or the bowel impairs availability of intrinsic factor and limits absorption of vitamin B12.Symptoms of Pernicious Anemia:-Symptoms-abdominal distress such as nausea and vomiting.-burning on the tongue.-Neurological disturbances-Numbness-Weakness-Peculiar yellow and blue color blindnessTreatment of Pernicious Anemia: -Vitamin B12 supplementation-Vitamin B12 cannot be absorbed into the bloodstream, so it must be replaced by injection. -Vitamin B12 supplementation is required for life for strict vegetarians, those with chronic bowel disorders, or individuals who have had their stomach or bowel partially or fully removed.Folic Acid Deficiency Anemia- Risks and Etiology:-Most common in the Western world where consumption of raw fruits and vegetables is low -Fruits & veggies are the primary dietary source of folic acid.-Inflammation of the bowel (e.g., Crohn’s disease) and other adverse conditions.-Certain medications impair absorption of folic acid.-Especially at-risk groups (due to increased metabolic demands):-Pregnant and lactating females-Alcoholics-Individuals with kidney diseaseDiagnosis and Treatment of Folic Acid Deficiency Anemia:-Body stores of folic acid are small and therefore folic acid deficiency anemia occurs within a few months.-Measurement of serum folic acid levels is conclusive for folic acid deficiency anemia.-Oral folic acid supplementation is effective in replacing folic acid and meeting increased requirements for those with increased metabolic demands.Hemolytic Anemia Etiology:-Reduction in circulating red blood cells that is caused by pathological conditions that acceleratedestruction of red blood cells.-Inherited abnormalities that reduce RBC survival