Anemia (continued)

Anemia Caused by Inadequate Production of RBCs

Aplastic anemia occurs when the bone marrow can't make enough RBCs. This can be due to a viral infection, or exposure to certain toxic chemicals, radiation, or medications (such as antibiotics, antiseizure drugs, or cancer treatments). Some childhood cancers can also cause aplastic anemia, as can certain chronic diseases that affect the ability of the bone marrow to make blood cells.

High levels of hemoglobin and RBCs help fetal blood carry enough oxygen to developing babies in the relatively oxygen-poor environment in utero. After the child is born, more oxygen is available and the baby's hemoglobin level normally drops to a low point at about 2 months of age, a condition known as physiologic anemia of infancy. This temporary and expected drop in the blood count is considered normal and no treatment is required because the infant's body soon starts making RBCs on its own.

Anemia also occurs when the body isn't able to produce enough healthy RBCs because of an iron deficiency. Iron is essential to hemoglobin production. Poor dietary iron intake (or excessive loss of iron from the body) can lead to iron deficiency anemia, the most common cause of anemia in kids. Iron deficiency anemia can affect kids at any age, but is most common in those younger than 2 years old. Young children who drink excessive amounts of milk are at increased risk for iron deficiency.

Girls going through puberty also have a particularly high risk for iron deficiency anemia because of the onset of menstruation; the monthly blood loss increases the amount of iron they need to consume in their diets.

Signs and Symptoms

If your child has anemia, the first symptoms might be mild skin paleness and decreased pinkness of the lips and nailbeds. These changes may happen gradually, though, so they can be difficult to notice. Other common signs include:

• irritability
• fatigue
• dizziness, lightheadedness, and a rapid heartbeat

If the anemia is caused by excessive destruction of RBCs, symptoms also may include jaundice, a yellowing of the whites of the eyes, an enlarged spleen, and dark tea-colored urine.

In infants and preschoolers, iron deficiency anemia can result in developmental delays and behavioral disturbances, such as decreased motor activity and problems with social interaction and attention to tasks. Research indicates that developmental problems may last into and beyond school age if the iron deficiency is not properly treated.

Diagnosing Anemia

In many cases, doctors don't diagnose anemia until they run blood tests as part of a routine physical examination. A complete blood count (CBC) may indicate that there are fewer RBCs than normal. Other diagnostic tests may include:

• Blood smear examination: Blood is smeared on a glass slide for microscopic examination of RBCs, which can sometimes indicate the cause of the anemia.
• Iron tests: These include total serum iron and ferritin tests, which can help to determine whether anemia is due to iron deficiency.
• Hemoglobin electrophoresis: Used to identify various abnormal hemoglobins in the blood and to diagnose sickle cell anemia, the thalassemias, and other inherited forms of anemia.
• Bone marrow aspiration and biopsy: This test can help determine whether cell production is happening normally in the bone marrow. It's the only way to diagnose aplastic anemia definitively and is also used if a disease affecting the bone marrow (such as leukemia) could be causing of the anemia.
• Reticulocyte count: A measure of young RBCs, this helps to determine if RBC production is at normal levels.

In addition to running these tests, your doctor may ask about a family history of anemia and your child's symptoms and medications. This may lead the doctor to perform other tests to look for specific diseases that might be causing the anemia.