Anemia, one of the more common blood disorders, occurs when the level of healthy red blood cells (RBCs) in the body becomes too low. This can lead to health problems because RBCs contain hemoglobin, which carries oxygen to the body's tissues. Anemia can cause a variety of complications, including fatigue and stress on bodily organs.
Anemia can be caused by many things, but the three main bodily mechanisms that produce it are:
Among many other causes, anemia can result from inherited disorders, nutritional problems (such as an iron or vitamin deficiency), infections, some kinds of cancer, or exposure to a drug or toxin.
Anemia Caused by Destruction of RBCs
Hemolytic anemia occurs when red blood cells are being destroyed prematurely. (The normal lifespan of RBCs is 120 days; in hemolytic anemia, it's much shorter.) And the bone marrow (the soft, spongy tissue inside bones that makes new blood cells) simply can't keep up with the body's demand for new cells. This can happen for a variety of reasons. Sometimes, infections or certain medications — such as antibiotics or anti-seizure medicines — are to blame.
In autoimmune hemolytic anemia, the immune system mistakes RBCs for foreign invaders and begins destroying them. Other kids inherit defects in the red blood cells that lead to anemia; common forms of inherited hemolytic anemia include sickle cell anemia, thalassemia, glucose-6-phosphate dehydrogenase (G6PD) deficiency, and hereditary spherocytosis.
Anemia Caused by Blood Loss
Blood loss can also cause anemia — whether it's because of excessive bleeding due to injury, surgery, or a problem with the blood's clotting ability. Slower, long-term blood loss, such as intestinal bleeding from inflammatory bowel disease (IBD), can also cause anemia. Anemia sometimes results from heavy menstrual periods in teen girls and women. Any of these factors will also increase the body's need for iron because iron is needed to make new RBCs.
Anemia Caused by Inadequate Production of RBCs
Aplastic anemia occurs when the bone marrow can't make enough blood cells. This can be due to a viral infection, or exposure to certain toxic chemicals, radiation, or medications (such as antibiotics, anti-seizure drugs, or cancer treatments). Some childhood cancers can also cause aplastic anemia, as can certain genetic and other chronic diseases that affect the ability of the bone marrow to function properly.
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:
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.
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:
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.
Treatment for anemia depends on its cause. It's important not to assume that any symptoms your child may be having are due to iron deficiency. Be sure to have your child checked by a doctor.
If your child has iron deficiency anemia, the doctor may prescribe medication as drops (for infants) or as a liquid or tablet (for older kids), which usually must be taken for as long as 3 months to rebuild the body's store of iron. The doctor also may recommend adding certain iron-rich foods to your child's diet or reducing milk intake.
If your teenage daughter is anemic and has heavy or irregular menstrual periods, her doctor may prescribe hormonal treatment to help regulate the bleeding.
Folic acid and vitamin B12 supplements may be prescribed if the anemia is traced to a deficiency of these nutrients, although this is rare in children.
Anemia caused by an infection will usually improve when the infection passes or is treated. If a certain medication appears to be the cause, your doctor may discontinue it or replace it with something else — unless the benefit of the drug outweighs this side effect.
Depending on the cause, treatment for more severe or chronic forms of anemia may include:
In some cases of sickle cell anemia, thalassemia, and aplastic anemia, bone marrow transplantation may be used. In this procedure, bone marrow cells taken from a donor are injected into the child's vein; they then travel through the bloodstream to the bone marrow and begin producing new blood cells.
Caring for a Child With Anemia
The type, cause, and severity of your child's anemia will determine what kind of care is needed. Rest assured, though, that kids often tolerate anemia much better than adults.
In general, a child with significant anemia may tire more easily than other kids and therefore need to limit activity levels. Make sure that your child's teachers and other caregivers are aware of the condition. If iron deficiency is the cause, follow the doctor's directions about dietary changes and taking any iron supplements.
If the spleen is enlarged, your child may be prohibited from playing contact sports because of the risk that the spleen could rupture or hemorrhage if your child is hurt. Certain forms of anemia, such as sickle cell anemia, require other more specific kinds of care and treatment.
Whether anemia can be prevented depends on its cause. Currently, there is no way to prevent anemia due to genetic defects affecting the production of RBCs or hemoglobin.
However, you can help prevent iron deficiency, the most common form of anemia. Before following any of these suggestions, be sure to talk them over with your doctor:
If you have any questions about anemia or you think your child might have it, speak with your doctor.
Reviewed by: Robin Miller, MD