Anemia

Anemia is not considerate to be a specific disease; it is a manifestation of

many abnormal conditions. Some of the abnormal conditions that causes

anemia include dietary deficiencies of iron, vitamin B12, and folic acid; hereditary

disorders; bone marrow damaged by toxins, radiation, or chemotherapy; renal disease; malignancy; chronic infection; overactive spleen; or bleeding from a tract or organ. The incidence of anemia in the world is very high. More than 50% of the world suffers from anemia.

Anemia is characterized by a deficiency in red blood cells or in the

concentration of hemoglobin (iron-containing portions of red blood cells). These

deficiencies are caused by either decreased production or increased destruction

of red blood cells. Anemia is most common among women in their reproductive

years (5.8 percent), infants (5.7 percent), and the elderly (12 percent). Because

one of the major functions of red blood cells is to transport oxygen, a decrease in

red blood cells decreases the amount of oxygen delivered to the body's tissues,

which results in the symptoms of anemia.

Anemia can be defined as a decrease in the oxygen-carrying capacity of the blood caused by low hemoglobin concentration (A Practical Guide, 1). Cells in the body require oxygen to fully utilize fuels. The oxygen is transported from the lungs to tissues throughout the body via red blood cells. Oxygen binds to hemoglobin, a specific molecule within each red blood cell. This molecule consists of heme, which is a red pigment, and globin, which is a protein. If the amount of functioning hemoglobin is reduced, a condition known as anemia arises (Anemia, 1). The anemia that may result can take many forms, including that caused by a low iron level (iron deficiency anemia), a vitamin deficiency (megaloblastic anemia), a thyroid deficiency, the premature destruction of red blood cells (hemolytic anemia), replacement of normal bone marrow cells by cancer cells or leukemia (myelophthisic anemia), injury to bone marrow (aplastic anemia), and inborn structural defect in red blood cells (e.g. sickle-cell anemia), inhibition of erythropoietin production by the immune system (anemia of chronic disease), and a normal or high iron level but an inability to manufacture hemoglobin or make use of the iron (sideroblastic anemia) (Anemia, 2). There are also several other less common types of anemia including: aplastic anemia, Thalassemia, acquired hemolytic anemia, inherited hemolytic anemia, sickle cell anemia, and anemia caused by miscellaneous factors (Anemia, 3-4). All of these different types of anemia can be grouped into categories according to their causes and treatments. In all, more than 400 different forms of anemia have been identified, many of them rare.

Risk factors for Anemia are factors that do not seem to be a direct cause of the

disease, but seem to be associated in some way. Having a risk factor for Anemia makes

the chances of getting a condition higher but does not always lead to Anemia. Also, the

absence of any risk factors or having a protective factor does not necessarily guard you

against getting Anemia. Risk factors discussion: An iron deficit is not necessarily due to

poor eating habits, an otherwise balanced diet may not supply ample iron to women in

one of the following groups- menstruating, dieting, pregnant, vegetarian and women who

do not eat red-meat, as well as women who have trouble absorbing iron from their foods.

Menstruation: The monthly blood loss that occurs during menstruation causes the body to

need increased iron. Women who experience heavy bleeding should pay special attention

to their iron intake. Dieting: Since the average American women's diet does not reach the

RDA for iron, dieting and decreasing food intake will make it even more difficult to

reach the recommended RDA for iron. Pregnancy: Pregnant women are at an increased

risk for developing anemia, because the iron stores are placed at an increased demand

caused by the higher blood volume and demands of the fetus and placenta. Vegetarians:

Vegetarians and people who do not consume red-meat are more apt to be iron deficient.

Meat sources of iron, also called heme-iron, such pork, beef and lamb are among the

richest sources of iron. Heme-sources of iron are best absorbed and utilized by the body.

Non-heme sources such as the iron in beans, grains and vegetables is not nearly as well

absorbed by the body. Absorption: The capacity of the body to absorb iron from the diet

is a crucial factor for developing iron stores and maintaining functional iron. When the

body has trouble absorbing iron from foods or when iron is lost through cellular break

down, iron deficiency anemia is likely to occur.

When the above mechanisms are overwhelmed by the increasing magnitude of the anemia, or when the demands of physical activity or intercurrent illness overwhelm them, a clinical disease state becomes apparent to the physician and to the patient. The severity of clinical symptoms bears less relationship to the severity of the anemia than to the length of time over which the condition develops. An acute hemorrhagic condition may produce symptoms with loss of as little as 20% of the total blood volume (or 20% of the total red cell mass). Conversely, anemias developing over periods long enough to allow compensatory mechanisms to operate will allow much greater loss of rbc mass before producing symptoms. It is not terribly uncommon to see a patient with a hemoglobin of 4 g/dL (hematocrit 12 cL/L), representing a loss of 70% of the rbc mass, being reluctantly dragged