Iron Deficiency Anemia

What is this condition?

In iron deficiency anemia, a lack of iron in the body causes an array of symptoms, including fatigue, weakness, and abnormally pale skin. When the body’s iron stores are low, the red blood cell count falls, and with it the supply of hemoglobin, the iron-containing pigment in red cells that carries oxygen. The blood’s oxygen-carrying capacity is thereby diminished.

A common disease worldwide, iron deficiency anemia affects 10% to 30% of adults in the United States. It’s most prevalent in premenopausal women, infants (especially premature or low-birth-weight infants), children, and adolescents (especially girls).

What causes it?

Iron deficiency anemia may result from:

• too little iron in the diet, as in prolonged unsupplemented breast­or bottle-feeding of infants or during periods of stress, such as rapid growth in children and adolescents

• iron malabsorption, as in chronic diarrhea, surgical removal of the stomach, and malabsorption syndromes

• blood loss caused by heavy menstrual bleeding, injury, gastrointestinal ulcers, cancer, drug-induced gastrointestinal bleeding, or twisted, dilated veins

• pregnancy, which diverts the mother’s iron supply to the fetus for red blood cell formation

• abnormal presence in urine of free (extracellular) hemoglobin.

What are its symptoms?

Because iron deficiency progresses slowly, many people have no symptoms at first (except those of any underlying condition). Typically, they don’t go to the doctor until anemia is severe. In advanced stages, they may have trouble breathing on exertion, fatigue, weakness, listlessness, pallor, inability to concentrate, irritability, headache, and susceptibility to infection. Also, the heart may pump more blood than usual and the pulse rate may increase.

Chronic iron deficiency anemia causes spoon-shaped and brittle nails, cracks in the corners of the mouth, a smooth tongue, and difficulty swallowing.

How is it diagnosed?

Blood tests and bone marrow studies may confirm iron deficiency anemia. However, test results may be misleading because of complicating factors, such as infection, pneumonia, blood transfusion, or iron supplements. Bone marrow studies may also provide important information about the disorder. The doctor also must rule out other forms of anemia.

How is it treated?

The first goal of treatment is to determine the underlying cause of anemia. Then, iron replacement can begin. The preferred treatment is an oral iron preparation or a combination of iron and ascorbic acid (which enhances iron absorption). However, some people may need iron injections – for instance, those who need more iron than they can take orally.