Erythrocyte Disorders Part 2

Flashcards covering the different types of Erythrocyte Disorders (Anemias)-Part 2

Anemia

From Greek word anaimia = 'without blood.' Physiologic effects include decreased Hb oxygen-affinity, tissue hypoxia, increased cardiac output, and increased RBC production.

Erythropoiesis

Marrow erythroid proliferative activity that can be effective (produce functional cells), ineffective (produce defective progenitor cells), or insufficient (lack of erythroid precursors).

Microcytic Anemia

Anemia characterized by MCV < 80 fL, including iron deficiency anemia, anemia of chronic disease, thalassemia, lead poisoning, and sideroblastic anemia.

Macrocytic Anemia

Anemia characterized by MCV > 100 fL, including megaloblastic and nonmegaloblastic anemias.

Dimorphic Anemia

Presence of both hypochromic and normochromic cells in peripheral blood, seen in sideroblastic anemia or after iron therapy for IDA.

Iron Deficiency Anemia (IDA)

Most common form of anemia, characterized by microcytic, hypochromic cells; develops when iron loss exceeds iron intake.

Sideroblastic Anemia

Anemia caused by enzymatic defects in protoporphyrin pathway, leading to defective heme synthesis and ringed sideroblasts in bone marrow.

Porphyrias

Inherited and acquired disorders of heme biosynthesis caused by a deficiency of a specific enzyme in the biosynthetic pathway.

Nonmegaloblastic Anemia

Macrocytic anemia with normoblastic marrow, caused by early release of erythrocytes (shift reticulocytes) due to liver disease, blood loss, hemolysis, etc.

Megaloblastic Anemia

Anemia characterized by macroovalocytes, hypersegmented neutrophils, and nuclear-cytoplasmic asynchrony; caused by diminished DNA synthesis.

Pernicious Anemia

Megaloblastic anemia caused by deficiency of intrinsic factor needed for vitamin B12 absorption.

Chronic Disease Anemia (ACD)

Anemia associated with chronic nonhematologic disorders, leading to defective iron utilization and increased hepcidin levels.

Anemia of Renal Insufficiency

Normocytic, normochromic anemia associated with burr cells; caused by decreased EPO production.

Myelophthisic Anemia

Anemia associated with bone marrow infiltration by nonerythroid cells; accompanied by leukoerythroblastic reaction.

Refractory Anemia

Anemia usually occurring in individuals over 50, characterized by reticulocytopenia and hypercellular marrow; now classified as myelodysplastic syndrome.

Pure Red Cell Aplasia

Unusual disease characterized by selective depletion of erythroid bone marrow tissue.

Aplastic Anemia

Marrow disorder characterized by a reduction in multipotential stem cells, resulting in pancytopenia.

Congenital Dyserythropoietic Anemia (CDA)

Family of inherited refractory anemias characterized by ineffective erythropoiesis and marrow erythroid multinuclearity.

Hemoglobinopathies

Genetic defect resulting in an abnormal structure of globin chains in hemoglobin.

Thalassemias

Anemia caused by abnormally long or short polypeptide chains resulting from genetic errors, leading to deficiency or absence of globin chains.

Hemolytic Anemias

Anemias occurring with increased RBC destruction and shortened cell survival; can be intrinsic (hereditary) or extrinsic (acquired).

Hereditary Spherocytosis (HS)

Most common membrane defect, caused by a defect in spectrin, leading to increased RBC destruction and splenomegaly.

Paroxysmal Nocturnal Hemoglobinuria (PNH)

Acquired, intrinsic red cell defect rendering cells susceptible to complement-mediated intravascular lysis.

Warm Autoimmune Hemolytic Anemia (WAIHA)

Extrinsic hemolytic anemia where RBCs are coated with IgG and/or complement.

Cold Autoimmune Hemolytic Anemia (CAIHA)

Extrinsic hemolytic anemia where RBCs are coated with IgM and complement.

Glucose-6-Phosphate Dehydrogenase (G6PD) Deficiency

Most common enzyme deficiency in the hexose monophosphate shunt, leading to accumulation of intracellular oxidants and Heinz bodies.

Pyruvate Kinase (PK) Deficiency

Most common enzyme deficiency in the Embden-Meyerhof pathway, leading to lack of ATP and impairment of the cation pump.

Acute Posthemorrhagic Anemia

Anemia characterized by a sudden loss of blood; normocytic, normochromic.

Chronic Posthemorrhagic Anemia

Anemia characterized by a gradual, long-term loss of blood; normocytic, normochromic or microcytic, hypochromic.