Alterations of Erythrocyte Function Chapter 26 1 Anemia

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Alterations of Erythrocyte Function Chapter 26 1

Alterations of Erythrocyte Function Chapter 26 1

Anemia o Reduction in the total number of erythrocytes in the circulating blood or

Anemia o Reduction in the total number of erythrocytes in the circulating blood or in the quality or quantity of hemoglobin n n Impaired erythrocyte production Acute or chronic blood loss Increased erythrocyte destruction Combination of the above 2 Mosby items and derived items © 2006 by Mosby, Inc.

Anemia o Classifications n n Etiology Morphology o o Based on MCV, MCH, and

Anemia o Classifications n n Etiology Morphology o o Based on MCV, MCH, and MCHC values Size n n o Identified by terms that end in -cytic Macrocytic, microcytic, normocytic Hemoglobin content n n Identified by terms that end in -chromic Normochromic and hypochromic 3 Mosby items and derived items © 2006 by Mosby, Inc.

Anemia o Anisocytosis n o Red cells are present in various sizes Poikilocytosis n

Anemia o Anisocytosis n o Red cells are present in various sizes Poikilocytosis n Red cells are present in various shapes 4 Mosby items and derived items © 2006 by Mosby, Inc.

Anemia o Physiologic manifestation n o o Reduced oxygen carrying capacity Variable symptoms based

Anemia o Physiologic manifestation n o o Reduced oxygen carrying capacity Variable symptoms based on severity and the ability for the body to compensate Classic anemia symptoms n Fatigue, weakness, dyspnea, and pallor 5 Mosby items and derived items © 2006 by Mosby, Inc.

Macrocytic-Normochromic Anemias o o Also termed megaloblastic anemias Characterized by defective DNA synthesis n

Macrocytic-Normochromic Anemias o o Also termed megaloblastic anemias Characterized by defective DNA synthesis n Due to deficiencies in vitamin B 12 or folate o o Coenzymes for nuclear maturation and the DNA synthesis pathway Ribonucleic acid (RNA) processes occur at a normal rate n Results in the unequal growth of the nucleus and cytoplasm 6 Mosby items and derived items © 2006 by Mosby, Inc.

Macrocytic-Normochromic Anemias o Pernicious anemia n n n Caused by a lack of intrinsic

Macrocytic-Normochromic Anemias o Pernicious anemia n n n Caused by a lack of intrinsic factor from the gastric parietal cells Required for vitamin B 12 absorption Results in vitamin B 12 deficiency 7 Mosby items and derived items © 2006 by Mosby, Inc.

Macrocytic-Normochromic Anemias o Pernicious anemia n n Typical anemia symptoms Neurologic manifestations o n

Macrocytic-Normochromic Anemias o Pernicious anemia n n Typical anemia symptoms Neurologic manifestations o n Others o n Nerve demyelination Loss of appetite, abdominal pain, beefy red tongue (atrophic glossitis), icterus, and splenic enlargement Treatment o Parenteral or high oral doses of vitamin B 12 8 Mosby items and derived items © 2006 by Mosby, Inc.

Pernicious Anemia 9 Mosby items and derived items © 2006 by Mosby, Inc.

Pernicious Anemia 9 Mosby items and derived items © 2006 by Mosby, Inc.

Macrocytic-Normochromic Anemias o Folate deficiency anemia n n Absorption of folate occurs in the

Macrocytic-Normochromic Anemias o Folate deficiency anemia n n Absorption of folate occurs in the upper small intestine Not dependent on any other facilitating factor Similar symptoms to pernicious anemia except neurologic manifestations are generally not seen Treatment requires daily oral administration of folate 10 Mosby items and derived items © 2006 by Mosby, Inc.

Microcytic-Hypochromic Anemias o o Characterized by red cells that are abnormally small and contain

Microcytic-Hypochromic Anemias o o Characterized by red cells that are abnormally small and contain reduced amounts of hemoglobin. Related to: n n n Disorders of iron metabolism Disorders of porphyrin and heme synthesis Disorders of globin synthesis 11 Mosby items and derived items © 2006 by Mosby, Inc.

Microcytic-Hypochromic Anemias o Iron deficiency anemia n n Most common type of anemia worldwide

Microcytic-Hypochromic Anemias o Iron deficiency anemia n n Most common type of anemia worldwide Nutritional iron deficiency Metabolic or functional deficiency Progression of iron deficiency causes: o o Brittle, thin, coarsely ridged, and spoon-shaped nails A red, sore, and painful tongue 12 Mosby items and derived items © 2006 by Mosby, Inc.

Iron Deficiency Anemia 13 Mosby items and derived items © 2006 by Mosby, Inc.

Iron Deficiency Anemia 13 Mosby items and derived items © 2006 by Mosby, Inc.

Microcytic-Hypochromic Anemias o Sideroblastic anemia n n n Group of disorders characterized by anemia

Microcytic-Hypochromic Anemias o Sideroblastic anemia n n n Group of disorders characterized by anemia Altered mitochondrial metabolism causing ineffective iron uptake and resulting in dysfunctional hemoglobin synthesis Ringed sideroblasts within the bone marrow are diagnostic o Sideroblasts are erythroblasts that contain iron granules that have not been synthesized into hemoglobin 14 Mosby items and derived items © 2006 by Mosby, Inc.

Microcytic-Hypochromic Anemias o Sideroblastic anemia n n n Dimorphism Myelodysplastic syndrome Erythropoietic hemochromatosis 15

Microcytic-Hypochromic Anemias o Sideroblastic anemia n n n Dimorphism Myelodysplastic syndrome Erythropoietic hemochromatosis 15 Mosby items and derived items © 2006 by Mosby, Inc.

Normocytic-Normochromic Anemias o Characterized by red cells that are relatively normal in size and

Normocytic-Normochromic Anemias o Characterized by red cells that are relatively normal in size and hemoglobin content but insufficient in number 16 Mosby items and derived items © 2006 by Mosby, Inc.

Normocytic-Normochromic Anemias o Aplastic anemia n n n o Pancytopenia Pure red cell aplasia

Normocytic-Normochromic Anemias o Aplastic anemia n n n o Pancytopenia Pure red cell aplasia Fanconi anemia Posthemorrhagic anemia n Acute blood loss from the vascular space 17 Mosby items and derived items © 2006 by Mosby, Inc.

Normocytic-Normochromic Anemias o Hemolytic anemia n n n n Accelerated destruction of red blood

Normocytic-Normochromic Anemias o Hemolytic anemia n n n n Accelerated destruction of red blood cells Autoimmune hemolytic anemias Immunohemolytic anemia Warm antibody immunohemolytic anemia Drug-induced hemolytic anemia Cold agglutinin immunohemolytic anemia Cold hemolysin hemolytic anemia 18 Mosby items and derived items © 2006 by Mosby, Inc.

Drug-Induced Hemolytic Anemia 19 Mosby items and derived items © 2006 by Mosby, Inc.

Drug-Induced Hemolytic Anemia 19 Mosby items and derived items © 2006 by Mosby, Inc.

Normocytic-Normochromic Anemias o o Sickle cell anemia Anemia of chronic inflammation n Mild to

Normocytic-Normochromic Anemias o o Sickle cell anemia Anemia of chronic inflammation n Mild to moderate anemia seen in: o n AIDS, rheumatoid arthritis, lupus erythematosus, hepatitis, renal failure, and malignancies Pathologic mechanisms o o o Decreased erythrocyte life span Ineffective bone marrow response to erythropoietin Altered iron metabolism 20 Mosby items and derived items © 2006 by Mosby, Inc.

Anemia of Chronic Inflammation 21 Mosby items and derived items © 2006 by Mosby,

Anemia of Chronic Inflammation 21 Mosby items and derived items © 2006 by Mosby, Inc.

Myeloproliferative RBC Disorders o Polycythemia n o Overproduction of red blood cells Relative polycythemia

Myeloproliferative RBC Disorders o Polycythemia n o Overproduction of red blood cells Relative polycythemia n n Result of dehydration Fluid loss results in relative increases of red cell counts and Hgb and Hct values 22 Mosby items and derived items © 2006 by Mosby, Inc.

Polycythemia o Absolute polycythemia n Primary absolute o o n Abnormality of stem cells

Polycythemia o Absolute polycythemia n Primary absolute o o n Abnormality of stem cells in the bone marrow Polycythemia vera (PV) Secondary absolute o Increase in erythropoietin as a normal response to chronic hypoxia or an inappropriate response to erythropoietin-secreting tumors 23 Mosby items and derived items © 2006 by Mosby, Inc.