normocytic anemia

anemia /ane·mia/ (ah-ne´me-ah) reduction below normal of the number of erythrocytes, quantity of hemoglobin, or the volume of packed red cells in the blood; a symptom of various diseases and disorders.ane´mic

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achrestic anemia  any of various types of megaloblastic anemia resembling pernicious anemia but unresponsive to therapy with vitamin B12.

aplastic anemia  a diverse group of anemias characterized by bone marrow suppression with replacement of the hematopoietic cells by fat, which causes pancytopenia, often accompanied by granulocytopenia and thrombocytopenia.

autoimmune hemolytic anemia  AIHA; a general term covering a large group of anemias involving autoantibodies against red cell antigens; they may be idiopathic or may have any of a number of causes, including autoimmune disease, hematologic neoplasms, viral infections, or immunodeficiency disorders.

aregenerative anemia  anemia characterized by bone marrow failure, so that functional marrow cells are regenerated slowly or not at all.

Blackfan-Diamond anemia  congenital hypoplastic a. (1).

congenital hypoplastic anemia 

1. a progressive anemia of unknown etiology seen in the first year of life, with deficiency of red cell precursors in an otherwise normally cellular bone marrow; it is unresponsive to hematinics.

2. Fanconi's syndrome (1).

congenital nonspherocytic hemolytic anemia  any of a heterogeneous group of inherited anemias characterized by shortened red cell survival, lack of spherocytosis, and normal osmotic fragility with erythrocyte membrane defects, multiple intracellular enzyme deficiencies or other defects, or unstable hemoglobins.

Cooley's anemia  thalassemia major.

drug-induced immune hemolytic anemia  immune hemolytic anemia produced by drugs, classified as the penicillin type, in which the drug induces the formation of specific antibodies; the methyldopa type, in which the drug induces the formation of anti-Rh antibodies; and the stibophen type, in which circulating drug-antibody complexes bind to red cells.

equine infectious anemia  a viral disease of equines, with recurring malaise and abrupt temperature rises, weight loss, edema, and anemia; transmission to humans has been suggested, in whom it causes anemia, neutropenia, and relative lymphocytosis.

Fanconi's anemia  Fanconi's syndrome (1).

hemolytic anemia  any of a group of acute or chronic anemias, inherited or acquired, characterized by shortened survival of mature erythrocytes and inability of bone marrow to compensate for the decreased life span.

hereditary iron-loading anemia  hereditary sideroblastic a.

hereditary sideroachrestic anemia  hereditary sideroblastic a.

hereditary sideroblastic anemia  an X-linked anemia characterized by ringed sideroblasts, hypochromic, microcytic erythrocytes, poikilocytosis, weakness, and later by iron overload.

hookworm anemia  hypochromic microcytic anemia resulting from infection with Ancylostoma or Necator; see also under disease.

hypochromic anemia  that characterized by a disproportionate reduction of red cell hemoglobin and an increased area of central pallor in the red cells.

hypoplastic anemia  that due to varying degrees of erythrocytic hypoplasia without leukopenia or thrombocytopenia.

iron deficiency anemia  a form characterized by low or absent iron stores, low serum iron concentration, low transferrin saturation, elevated transferrin, low hemoglobin concentration or hematocrit, and hypochromic, microcytic red blood cells.

macrocytic anemia  a group of anemias of varying etiologies, marked by larger than normal red cells, absence of the customary central area of pallor, and an increased mean corpuscular volume and mean corpuscular hemoglobin.

Mediterranean anemia  thalassemia major.

megaloblastic anemia  any anemia characterized by megaloblasts in the bone marrow, such as pernicious a.

microcytic anemia  that marked by decrease in size of the red cells.

myelopathic anemia , myelophthisic anemia leukoerythroblastosis.

normochromic anemia  anemia in which the hemoglobin content of the red cells as measured by the MCHC is in the normal range.

normocytic anemia  that marked by a proportionate decrease in the hemoglobin content, the packed red cell volume, and the number of erythrocytes per cubic millimeter of blood.

pernicious anemia  megaloblastic anemia, most commonly affecting older adults, due to failure of the gastric mucosa to secrete adequate and potent intrinsic factor, resulting in malabsorption of vitamin B12.

polar anemia  an anemic condition that occurs during exposure to low temperature; initially microcytic, but subsequently becoming normocytic.

pure red cell anemia  anemia characterized by absence of red cell precursors in the bone marrow; the congenital form is called congenital hypoplastic a.

refractory normoblastic anemia  refractory sideroblastic a.

refractory sideroblastic anemia  a sideroblastic anemia clinically similar to the hereditary sideroblastic form but occurring in adults and often only slowly progressive. It is unresponsive to hematinics or to withdrawal of toxic agents or drugs and may be preleukemic.

sickle cell anemia  an autosomal dominant type of hemolytic anemia, seen primarily in those of West African descent, and less often in the Mediterranean basin and a few other areas; it is caused by hemoglobin S with abnormal erythrocytes (sickle cells) in the blood. Homozygous individuals have the full-blown syndrome with accelerated hemolysis, increased blood viscosity and vaso-occlusion, arthralgias, acute attacks of abdominal pain, and ulcerations of the lower limbs; some have periodic attacks of sickle cell crises. The heterozygous condition is called sickle cell trait and is usually asymptomatic.

sideroachrestic anemia  sideroblastic a.

sideroblastic anemia  any of a group of anemias that may have diverse clinical manifestations; commonly characterized by large numbers of ringed sideroblasts in the bone marrow, ineffective erythropoiesis, variable proportions of hypochromic erythrocytes in the peripheral blood, and usually increased levels of tissue iron.

sideropenic anemia  a group of anemias marked by low levels of iron in the plasma; it includes iron deficiency anemia and the anemia of chronic disorders.

spur cell anemia  anemia in which the red cells have a bizarre spiculated shape and are destroyed prematurely, primarily in the spleen; it is an acquired form occurring in severe liver disease and represents an abnormality in the cholesterol content of the red cell membrane.

toxic hemolytic anemia  that due to toxic agents, including drugs, bacterial lysins, and snake venoms.

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nor·mo·cyt·ic anemia (nôrm-stk)

n.

Anemia in which the red blood cells are normal in size.

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anemia

a reduction below normal in the number or volume of erythrocytes or in the quantity of hemoglobin in the blood. Clinically it is manifested by weakness, exercise intolerance, hyperpnea which is only moderate, pallor of mucosae, tachycardia and a large increase in the intensity of the heart sounds. There are often accompanying signs related to the site of blood or hemoglobin loss.

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aplastic anemia

a form of anemia generally unresponsive to specific antianemia therapy. It is often chronic, accompanied by granulocytopenia and thrombocytopenia, in which the bone marrow is usually acellular or hypoplastic. It may, however, be rapidly fatal. The term is actually all-inclusive and most probably encompasses several clinical syndromes. See pure red cell aplasia.

autoimmune hemolytic anemia

immune-mediated hemolytic anemia, which occurs in many species, particularly dogs, in which autoantibodies directed against red blood cells are produced. Different classes of immunoglobulins may be involved giving rise to differing clinical syndromes. Signs include pallor, lethargy, splenomegaly, and sometimes icterus, bilirubinuria and hemoglobinuria. There may also be an accompanying thrombocytopenia with bleeding tendencies. Diagnosis is based on a positive Coombs test.

avian infectious anemia

see chicken anemia.

blood loss anemia

see hemorrhagic anemia (below).

anemia of chronic disease

see anemia of inflammatory disease (below).

cold antibody anemia

an immune-mediated hemolytic anemia in which the antibody is maximally active at temperatures below 98.6°F (37°C). See also cold agglutinin disease.

cold (or cold water) anemia

a disease of cattle, especially calves, housed in warm barns and given near freezing water to drink. Dyspnea and the passage of red urine occur several hours after a large drink.

Coombs-positive anemia

immunoglobulin-mediated anemia that gives a positive reaction to Coombs tests, indicating the presence of immunoglobulins on the red cell surface. See also autoimmune hemolytic anemia (above), alloimmune hemolytic anemia of the newborn.

deficiency anemia

nutritional anemia.

drug-induced hemolytic anemia

some drugs such as quinine, quinidine, para-aminosalicylic acid, phenacetin, penicillin, insecticides, chlorpromazine, sulfonamides and dipyrone may be directly injurious to red cells or act to initiate an immune response in which red cells are destroyed.

familial nonspherocytic anemia of Basenji dogs

an inherited pyruvate kinase deficiency causes a hemolytic anemia with shortened red cell life span. In early stages, the disease is characterized by very active erythropoiesis but eventually, usually by the second or third year of life, a terminal myelofibrosis and osteosclerosis develops. The disease is inherited as an autosomal recessive trait.

feline infectious anemia

see feline infectious anemia.

fragmentation anemia

see microangiopathic anemia (below).

Heinz body anemia

hemolytic anemia resulting from oxidation of globin and formation of Heinz bodies, which are seen in blood smears as dark refractile intracytoplasmic bodies and stain with new methylene blue. Some common causes are ingestion of onions and plants in the Brassicaeae family, phenazopyridine, methylene blue and acetaminophen (paracetamol). Cats are particularly susceptible to Heinz body formation.

hemolytic anemia

see hemolytic anemia.

hemorrhagic anemia

is caused by loss of whole blood. If this is very rapid hypovolemic shock develops. At a slower rate there is anemic anoxia and the animal is suffering from anemia. Called also blood loss anemia.

hypochromic anemia

anemia in which the decrease in hemoglobin is proportionately much greater than the decrease in number of erythrocytes.

hypoplastic anemia

anemia due to incapacity of blood-forming organs, i.e. inactivity of the bone marrow. See also aplastic anemia (above).

idiopathic immune anemia

see autoimmune hemolytic anemia (above).

infectious equine anemia

see equine infectious anemia.

anemia of inflammatory disease

a nonregenerative, usually mild, anemia that occurs in association with malignancy or chronic infection. Although other causes of anemia such as hemolysis and blood loss may also occur with these conditions, there is altered iron metabolism with decreased serum iron and iron-binding capacity but with increased iron storage that results in decreased erythropoiesis.

iron-deficiency anemia

a form characterized by low or absent iron stores, low serum iron concentration, low transferrin saturation, elevated transferrin (iron-binding capacity), low hemoglobin concentration or hematocrit, and hypochromic, microcytic red blood corpuscles, and thrombocytosis. See also iron.

isoimmune hemolytic anemia

see alloimmune hemolytic anemia of the newborn.

lizard viral anemia

produces inclusion bodies in erythrocytes, commonly mistaken for protozoan parasites.

macrocytic anemia

anemia in which the erythrocytes are much larger than normal. The MCV (mean corpuscular volume) and MCH (mean corpuscular hemoglobin) are increased and the MCHC (mean corpuscular hemoglobin concentration) is normal.

megaloblastic anemia

anemia characterized by the presence of megaloblasts in the bone marrow and macrocytic erythrocytes. It occurs in vitamin B₁₂, cobalt and folic acid deficiencies and in some myeloproliferative disorders in cats.

microangiopathic anemia

anemia due to fragmentation of erythrocytes in blood vessels whose endothelium has been badly damaged, usually by an infectious disease such as septicemias, disseminated intravascular coagulation and salmonellosis. Called also fragmentation anemia.

microcytic anemia

anemia characterized by decrease in size of the erythrocytes.

myelopathic anemia, myelophthisic anemia

anemia due to destruction or crowding out of hematopoietic tissues by space-occupying lesions, neoplasms and fibrosis.

nonregenerative anemia

one occurring without an appropriate erythropoietic response by the bone marrow.

normochromic anemia

that in which the hemoglobin content of the red cells as measured by the MCHC and MCH is within the normal range.

normocytic anemia

the anemia in which the red blood cells are normal in size.

nutritional anemia

anemia due to a deficiency of an essential substance in the diet, which may be caused by poor dietary intake or by malabsorption; called also deficiency anemia. See also pyridoxine, vitamin b12, folic acid, copper, iron.

parasitic anemia

hemorrhagic anemia due to blood loss caused by blood-sucking parasites such as fleas, hookworms and Haemonchus contortus.

pernicious anemia

see pernicious anemia.

physiological anemia

the anemia which occurs as part of a natural event, e.g. in neonates.

piglet anemia

see iron nutritional deficiency.

primary immune anemia

see autoimmune hemolytic anemia (above).

regenerative anemia, responsive anemia

associated with active erythropoiesis with increased numbers of reticulocytes, nucleated red blood cells, anisocytosis and polychromasia in the peripheral blood.

spur-cell anemia

anemia in which the red cells have a bizarre spiculated shape and are destroyed prematurely, primarily in the spleen; it is an acquired form occurring in severe liver disease, and represents an abnormality in the cholesterol content of the red cell membrane.

unresponsive anemia

see nonregenerative anemia (above).