Anemia is any condition in which the concentration of hemoglobin in the blood is below the normal for the age and sex of the patient; usually there is also a reduction in the number of red blood cells per mm3 and in the volume of packed red blood cells per 100 ml of blood. Anemia decreases the oxygen-carrying capacity of the blood.
aplastic a. Anemia due to failure of bone marrow to produce the normal number of red blood cells for discharge into the bloodstream; usually associated with a reduction of all cellular components of the blood.
congenital hypoplastic a. Anemia occurring in infants, resulting from underdevelopment of bone marrow; may be associated with minor congenital abnormalities.
Cooley’s a. See beta thalassemia major, under thalassemia.
folic acid deficiency a. Anemia occurring in pregnant women secondary to folic acid
deficiency; marked by the presence of large embryonic red blood cells in bone marrow; it disappears after delivery but may recur in subsequent pregnancies.
hemolytic a. Anemia resulting from abnormal destruction of red blood cells in the body.
hypochromic a. Anemia marked by a reduction of hemoglobin content of red blood
cells, i.e., reduced mean corpuscular hemoglobin concentration.
hypochromic microcytic a. Anemia marked by a decrease of hemoglobin content of red blood cells, as in iron deficiency anemia.
hypoplastic a. Anemia resulting from inadequately functioning bone marrow.
iron deficiency a. Anemia developed when insufficient iron is available to the bone
marrow where red blood cells are formed; characterized by low concentration of hemoglobin and smaller than normal red blood cells. May be caused by dietary deficiency; increased demand for iron; malabsorption due to other conditions; or chronic blood loss.
macrocytic a. Any anemia in which the average size of circulating blood cells is greater than normal, i.e., the mean corpuscular volume is increased.
Marchiafava-Micheli a. See paroxysmal nocturnal hemoglobinuria, under hemoglobinuria.
megaloblastic a. Any anemia usually caused by deficiency of vitamin B or folic acid; characterized by macrocytic erythrocytes and an increased number of megaloblasts in the bone marrow; includes pernicious anemia and folic acid deficiency anemia.
myelophthisic a., myelopathic a. See leukoerythroblastosis.
normochromic a. Anemia in which hemoglobin concentration in red blood cells is within the normal range, i.e., the mean corpuscular hemoglobin concentration is from 32 to 36%.
pernicious a. Anemia due to vitamin B deficiency; usually caused by absence
of stomach acid and intrinsic factor, which are essential for absorption of vitamin B;
may also result from surgical removal of the terminal ileum where absorption takes place;
occurs mostly after the age of 50 years and is frequently associated with neurologic
sickle cell a. Hereditary chronic anemia in which a large number of red blood cells are crescent-shaped and contain an abnormal hemoglobin.
sideroblastic a., sideroachrestic a. Anemia in which the young erythrocytes in bone
marrow contain iron and the iron content of reticuloendothelial tissues is increased.