sickle cell 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

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.

sickle cell anemia

A chronic, usually fatal inherited form of anemia marked by crescent-shaped red blood cells, occurring almost exclusively in Blacks, and characterized by fever, leg ulcers, jaundice, and episodic pain in the joints. Also called crescent cell anemia, drepanocytic anemia, drepanocytosis, meniscocytosis, sickle cell disease, sickle cell syndrome.

Sickle cell anemia

An inherited disorder in which red blood cells contain an abnormal form of hemoglobin, a protein that carries oxygen. The abnormal form of hemoglobin causes the red cells to become sickle- or crescent-shaped. The misshapen cells may clog blood vessels, preventing oxygen from reaching tissues and leading to pain, blood clots and other problems. Sickle cell anemia is most common in people of African descent and in people from Italy, Greece, India, and the Middle East.

Mentioned in: Antianemia Drugs, Bone Marrow Transplantation, Budd-Chiari Syndrome, Cancer Therapy, Supportive, Fifth Disease, Immunologic Therapies, Pharmacogenetics, Priapism

sickle cell anemia,

a severe, chronic, incurable hemoglo-binopathic anemic condition that occurs in people homozygous for hemoglobin S (Hb S). The abnormal hemoglobin results in distortion and fragility of the erythrocytes. Sickle cell anemia is characterized by crises of joint pain, thrombosis, and fever and by chronic anemia, with splenomegaly, lethargy, and weakness. Also called drepanocytic anemia. See also congenital nonspherocytic hemolytic anemia, dactylitis, elliptocytosis, hemoglobin S, sickle cell crisis.

anemia [ah-ne´me-ah]

a condition in which there is reduced delivery of oxygen to the tissues; it is not actually a disease but rather a symptom of any of numerous different disorders and other conditions. The World Health Organization has defined anemia as a hemoglobin concentration below 7.5 mmol/L (12 g/dL) in women and below 8.1 mmol/L (13 g/dL) in men.

Peripheral blood smears from a patient with megaloblastic anemia (left) and from a normal subject (right), both at the same magnification. The smear from the patient shows variation in the size and shape of erythrocytes and the presence of macro-ovalocytes. From Goldman and Bennett, 2000.

Some types of anemia are named for the factors causing them: poor diet (nutritional anemia), excessive blood loss (hemorrhagic anemia), congenital defects of hemoglobin (hypochromic anemia), exposure to industrial poisons, diseases of the bone marrow (aplastic anemia and hypoplastic anemia), or any other disorder that upsets the balance between blood loss through bleeding or destruction of blood cells and production of blood cells. Anemias can also be classified according to the morphologic characteristics of the erythrocytes, such as size (microcytic, macrocytic, and normocytic anemias) and color or hemoglobin concentration (hypochromic anemia). A type called hypochromic microcytic anemia is characterized by very small erythrocytes that have low hemoglobin concentration and hence poor coloration. Data used to identify anemia types include the erythrocyte indices: (1) mean corpuscular volume (MCV), the average erythrocyte volume; (2) mean corpuscular hemoglobin (MCH), the average amount of hemoglobin per erythrocyte; and (3) mean corpuscular hemoglobin concentration (MCHC), the average concentration of hemoglobin in erythrocytes. adj., adj ane´mic.

Symptoms. Mild degrees of anemia often cause only slight and vague symptoms, perhaps nothing more than easy fatigue or a lack of energy. As the condition progresses, more severe symptoms may be experienced, such as shortness of breath, pounding of the heart, and a rapid pulse; these are caused by the inability of anemic blood to supply the body tissues with enough oxygen. Pallor, particularly in the palms of the hands, the fingernails, and the conjunctiva (the lining of the eyelids), may also indicate anemia. In very advanced cases, swelling of the ankles and other evidence of heart failure may appear.

Common Causes of Anemia. Loss of Blood (Hemorrhagic Anemia): If there is massive bleeding from a wound or other lesion, the body may lose enough blood to cause severe and acute anemia, which is often accompanied by shock. Immediate transfusions are generally required to replace the lost blood. Chronic blood loss, such as excessive menstrual flow, or slow loss of blood from an ulcer or cancer of the gastrointestinal tract, may also lead to anemia. These anemias disappear when the cause has been found and corrected. To help the blood replenish itself, the health care provider may prescribe medicines containing iron, which is necessary to build hemoglobin, and foods with high iron content, such as kidney and navy beans, liver, spinach, and whole wheat bread.

Dietary Deficiencies and Abnormalities of Red Blood Cell Production (Nutritional Anemia, Aplastic Anemia, and Hypoplastic Anemia): Anemia may develop if the diet does not provide enough iron, protein, vitamin B₁₂, and other vitamins and minerals needed in the production of hemoglobin and the formation of erythrocytes. The combination of poor diet and chronic loss of blood makes for particular susceptibility to severe anemia. Anemias associated with folic acid deficiency are very common.

Excessive Destruction of Red Blood Cells (hemolytic anemia): Anemia may also develop related to hemolysis due to trauma, chemical agents or medications (toxic hemolytic anemia), infectious disease, isoimmune hemolytic reactions, autoimmune disorders, and the paroxysmal hemoglobinurias.

Patient Care. Assessment of patients with some form of anemia will depend to some extent on the specific type of blood dyscrasia presented. In general, these patients do share some common problems requiring special assessment skills and interventions. Anemia can affect many different body systems

(see table). Although pallor of the skin is a sign of anemia, it is not the most reliable sign; many other factors can affect complexion and skin color. Jaundice of the skin and sclera can occur as a result of hemolysis and the release of bilirubin into the blood stream, where it eventually finds its way into the skin and mucous membranes. (See also jaundice.) Bleeding under the skin and bruises in response to the slightest trauma often are present in anemic and leukemic patients. A bluish tint to the skin (cyanosis) can indicate hypoxia due to inadequate numbers of oxygen-bearing erythrocytes.

Activity intolerance is a common problem for patients with anemia. Physical activity increases demand for oxygen, but if there are not enough circulating erythrocytes to provide sufficient oxygen, patients become physically weak and unable to engage in normal physical activity without experiencing profound fatigue. This can result in some degree of self-care deficit as the fatigue interferes with the patient's ability to carry on regular or enjoyable activities.

sickle cell disease any of the diseases associated with the presence of hemoglobin S, including sickle cell anemia, sickle cell–thalassemia, and the conditions called sickle cell–hemoglobin C and D disease. They are found most often in those of black African descent, but they also occur in persons of Mediterranean (Southern European and North African), Middle Eastern, or Asian Indian ancestry. About 8 to 10 per cent of all African Americans carry the sickle cell gene. About 90 per cent of persons with the gene are heterozygous for it, simply carriers of the sickle cell trait and usually without symptoms. The remainder, or about 1 in 500 of an ethnic group where the gene occurs, are homozygous for hemoglobin S, actually having sickle cell disease and suffering from the effects of hemolysis.

Sickle cell disease is a serious, hereditary, chronic disease in which the red blood cells have reduced life span and are rigid, with a crescent or sickle shape. The shape is the result of an abnormality in the hemoglobin, which alters the deformability of the cells under conditions of low oxygen tension. Because of their distorted shape the cells have difficulty passing through the small arterioles and capillaries and have a tendency to clump together and occlude the blood vessel. Some scientists believe that sickle cell disease developed as a defense against malaria. Malarial parasites do not grow in erythrocytes containing hemoglobin S. Therefore, carriers (heterozygotes) have an advantage in areas where malaria is prevalent (called the heterozygote advantage). (See accompanying figure.)

Symptoms. There are many symptoms of sickle cell disease, all of them related to the defective hemoglobin and its effect on red blood cells. Some persons with the condition suffer from only a few symptoms, while others are severely affected and have a short life span. Better understanding and management of the disease in recent decades has improved the prognoses for patients with it.

The major symptoms are anemia, periodic joint and limb pain and sometimes edema of the joints, chronic ulceration about the ankles, episodes of severe abdominal pain with vomiting, and abdominal distention. The spleen becomes infarcted so that it is essentially absent and predisposes the patient to infection with encapsulated organisms. Bone changes often can be seen on x-ray and are due to bone infarcts. Headache, paralysis, and convulsions may result from cerebral thrombosis, which can cause stroke, blindness, and other neurological disturbances. There is a tendency toward progressive renal disease and renal failure.

Sickle cell crisis is a broad term that describes several different conditions, particularly aplastic crisis, which is temporary bone marrow aplasia; hemolytic crisis, which is acute red cell destruction, leading to jaundice; and vaso-occlusive crisis, which is severe pain due to infarctions located in the bones, joints, lungs, liver, spleen, kidney, eye, or central nervous system. Factors that precipitate a crisis include infection, dehydration, trauma, strenuous physical exertion, emotional stress, and extremes of heat and cold.

Treatment and Care. There is no cure for sickle cell disease. Treatment is symptomatic; preventive measures are employed to reduce the incidence of crises and to avoid infections. It is also important that the patient receive all available immunizing agents. Nutritional deficiencies should be corrected when present (folate supplementation is especially important), and then a well-balanced dietary intake should be maintained. hydroxyurea and prophylactic penicillin are administered according to therapeutic guidelines. Social service programs are required to facilitate adjustment to the disease and its sequelae. Control of pain associated with this condition should be a priority.

Patient Care.

Sickle cell disease is a chronic condition with acute episodes related to vaso-occlusion. Virtually every system of the body can be affected by the ischemia resulting from obstruction of the blood vessels by clumps of deformed erythrocytes. Among the more common acute complications are inflammation of fingers and toes, aplastic anemia, splenic sequestration, and stroke. Chronic disorders include leg ulcers, renal complications, aseptic necrosis, and retinopathy. Bacterial infection is one of the major causes of morbidity and mortality in patients with sickle cell disease.

Because of the potential for serious complications due to occlusion of blood vessels, patients with sickle cell disease should have regular physical examinations to detect early changes. Periodic eye examinations are necessary to monitor retinal changes due to vaso-occlusion of retinal vessels.

Measures to improve or maintain the general well-being of patients include preventing dehydration, maintaining adequate nutrition to optimize the patient's resistance to infection and resources for healing, and managing the anemia that is characteristic of sickle cell disease. Education of patients and their parents and family members is an essential component of care. Patient support groups can be an effective mechanism to diffuse fear. Guidelines for the management of acute and chronic pain are available from the American Pain Society. A comprehensive biopsychosocial clinical assessment should be performed at least yearly.

The National Heart, Lung, and Blood Institute of NIH has published a guide called NIH Management and Therapy of Sickle Cell Disease. A printed copy is available as NIH publication number 95-2117. The guidelines are available online at http://www.emory.edu/peds/sickle/nih1/htm.

Clinicopathologic findings in sickle cell anemia. The findings are a consequence of infarctions, anemia, hemolysis, and recurrent infection. From Damjanov, 2000.

Mentioned in	?		References in periodicals archive	?		Medical browser	?		Full browser	?
acute chest syndrome anemia Anemias beta hemoglobinopathy crescent cell anemia drepanocytic anemia drepanocytosis erythrostasis hand-foot syndrome hemoglobin S hemoglobin SC disease hemoglobin SD disease Hemoglobinopathies hemoglobinopathy hemolytic anemia hyperviscosity syndrome meniscocyte meniscocytosis Ring Sign			Sickle cell disease or Sickle cell anemia is a type of blood related disorder where red blood cells are affected As we all know, hemoglobin is the key substance in the red blood cells which carries oxygen to lungs and other different parts of the human body Sickle cell disease or Sickle cell anemia is a type of blood related disorder where red blood cells are affected. Sickle Cell Disease Causes, Symptoms and Treatments by Serge Dandelin / Health care industry community Most of the cases have been reported among those suffering from sickle cell anemia, diabetes, kidney diseases, or cancer, and among children under two years of age," Jazairi pointed out. 2 die of swine flu in Basra by Aswat al-Iraq (Erbil, Iraq) The show will raise funds for Sickle Cell Anemia and tickets are available from 02476 449 072. Brown has top spot in his sights; KICKBOXING by Coventry Evening Telegraph (England)			sibship sibutramine sic sicc- sicca complex sicca syndrome siccant siccative siccus Sicilian ass Sicilian Gambit sick Sick Building Syndrome sick cell syndrome Sick Doctors’ Trust sick euthyroid syndrome sick headache sick leave sick role Sick Santa Syndrome sick sinus syndrome sickbay sickbed sickle sickle cell sickle cell anemia sickle cell C disease sickle cell crisis Sickle Cell Dactylitis sickle cell disease sickle cell hemoglobin sickle cell hepatopathy sickle cell retinopathy sickle cell syndrome sickle cell test sickle cell thalassemia sickle cell trait sickle cell-hemoglobin C disease sickle cell-hemoglobin D disease sickle cell-thalassemia disease sickle chest syndrome sickle hocks sickle scaler sickle shin Sickle-cell anemia sickle-cell test sickled erythrocyte sicklemia sicklepod sickling sickness			sicking on sicking on Sickingen Sickingen, Franz von Sickingen, Franz von sickish sickish sickish sickishly sickishness sickle sickle sickle sickle sickle sickle alfalfa Sickle and hammer Sickle and hammer sickle and sheaf of corn sickle cell sickle cell sickle cell sickle cell sickle cell sickle cell Sickle Cell Adult Provider Network Sickle Cell Advocates for Research and Empowerment, Inc. Sickle cell anaemia Sickle cell anaemia Sickle cell anaemia sickle cell anemia Sickle Cell Anemia Society of Arizona Sickle Cell Association Sickle Cell Association of Austin Sickle Cell Association of Kentuckiana Sickle Cell Association of Ontario sickle cell C disease Sickle Cell Carers Awareness Network Sickle cell crisis Sickle cell crisis Sickle cell crisis Sickle cell crisis Sickle cell crisis sickle cell dactylitis sickle cell disease sickle cell disease sickle cell disease sickle cell disease sickle cell disease sickle cell disease Sickle Cell Disease Association of America, Inc. Sickle Cell Disease Association of Illinois Sickle Cell Disease Association of the Piedmont Sickle Cell Disease Foundation of California Sickle Cell Disease Research Center sickle cell disorders sickle cell disorders Sickle Cell Foundation Nigeria Sickle Cell Foundation of Georgia Sickle Cell Foundation of Greater Montgomery, Inc. sickle cell hemoglobin