The blood circulating in our body is made up of
red blood cells, white blood cells, platelets, and plasma. The predominant cells in the
blood are the red blood cells whose primary function is to supply oxygen and nutrients to
the body’s cells and to remove waste products. While adequate delivery of oxygen is
important for everyone’s health, it is particularly important to the rapidly growing
child. The red blood cells can transport oxygen because they contain hemoglobin, a complex
protein that contains iron. Anemia results when the number of red blood cells is reduced
below normal, or there is a decrease in the amount of the body’s hemoglobin.
Fortunately, anemia has diminished as a major problem for children in the United States
because of improved nutrition. However, certain youngsters, particularly infants and
adolescent girls, remain at risk for developing anemia. If untreated, anemia can lead to
an impairment of a child’s normal growth and development.
Anemia is not a diagnosis, but is a sign, much as
fever may suggest the presence of an infectious disease. The exact cause of the anemia
must be found before the youngster can be properly treated. Children who are anemic are
often pale, irritable, tire easily, have a decreased appetite, and infection prone.
Adolescents may have impaired short-term memory, have decreased exercise tolerance, or
experience orthostatic hypotension (lightheadedness when changing position from lying or
sitting to standing).
The most common cause of anemia in children and
adolescents is due to iron deficiency, which results in a decreased production of new red
blood cells. The body normally obtains its iron supply from the diet and recycling of iron
from old red blood cells. Children at highest risk for developing this type of anemia are
premature infants, infants born of a multiple pregnancy, infants born of anemic mothers,
and children with inadequate dietary intake of iron. Adolescent girls are also at risk
because their irregular eating habits (caused by concerns about body image) compounded by
normal menstrual blood loss. Another less common cause of iron deficiency anemia in
children is gastrointestinal blood loss associated with ulcers and certain medications.
After birth, milk is the major source of iron.
Breast milk or commercially available formulas will supply the newborn with adequate
amounts of iron for at least the first six months of life. Iron fortified cereals are also
an important source of iron for young children. Because growth is so rapid during the
first year of life, iron intake might still not meet the demands of the growing child.
Therefore, many pediatricians screen the blood for anemia by getting a hemoglobin level at
the nine or twelve month well-baby checkup. A drop of blood from a simple fingertip
puncture is usually all that is needed. If the anemia is due to iron deficiency,
additional iron may be prescribed.
The typical American diet can usually meet the
body’s iron requirements after infancy. Iron-rich foods include meats (liver is the
highest source), poultry, egg yolks, dark leafy green vegetables, dried fruits and whole
grain bread. Milk is a poor source of iron after the age of one year.
Disorders of the hemoglobin (hemoglobinopathies),
such as sickle cell anemia and thalassemia, are also important causes of anemia in
Sickle cell anemia is an inherited condition in
which the red blood cells are destroyed faster than the body can replace them. The
hemoglobin in children with sickle cell anemia is different from normal hemoglobin. Two
genes are responsible for making a child’s hemoglobin molecule, one from the father
and the other from the mother. If both genes produce the abnormal hemoglobin, the child
has sickle cell disease. Severe anemia, delayed growth, and increased infections are
commonly found in children with sickle cell disease. On the other hand, if a child
receives a normal hemoglobin producing gene from one parent and one that produces the
sickle hemoglobin from the other parent, the child is said to have sickle cell trait.
Fortunately, sickle cell trait is not usually associated with significant anemia, and the
child grows and develops normally. About 8 percent of African Americans have the inherited
sickle cell trait. Children of two individuals with sickle cell trait have a one-in-four
chance of being born with sickle cell disease.
In thalassemia, the genes responsible for making
hemoglobin are distributed in an abnormal pattern or have defects, leading to a slowed
rate of hemoglobin production. Thalassemia occurs in people of Mediterranean origin, and
to a lesser extent, Chinese and African Americans. The "major" version of the
disease causes severe anemia during the first year of life producing growth failure,
abnormalities of the bones, and enlarged lifer and spleen. A milder form of the disease,
known as thalassemia minor, produces milder anemia and usually no symptoms.
Children may become anemic because of frequent
infections. Illness diminishes the youngster's appetite and slows the body’s
production of red blood cells. Deficiencies of folic acid or vitamin B-12 can also cause
anemia but are rare in youngsters, usually occurring because of impaired vitamin
absorption. Diseases of the bone marrow (the cavity within the larger bones) where the red
blood cells are produced will also cause anemia. Fortunately, these conditions are even
Worrying about their child’s health and if they could be
anemia is a common concern for many parents. Children do become anemic, but probably not
as often as most parents think. Thankfully, the diagnosis of anemia is easily made and in
the most cases treatment is easy, safe, and effective. Restoring a normal blood count can
literally breathe life into a less than active youngster. Most pediatricians screen the
blood for anemia during routine well-child checkups, and parents should always consult
with their child's physician if they suspect there is a problem.