Iron Deficiency and Down Syndrome

Key Points

• Iron deficiency occurs when a person does not have enough iron in their body. Iron deficiency anemia is the low red blood cell count that results from that deficiency.

• A complete blood count (CBC) measures whether a person has iron deficiency anemia.

• There are a variety of additional blood tests to assess for iron deficiency.

• In people with Down syndrome, a combination of tests is recommended when assessing for iron deficiency or iron deficiency anemia.

 

What is iron deficiency?

Iron deficiency is a condition in which the body does not have enough iron. Iron deficiency can cause anemia (low red blood cell count). This is called iron deficiency anemia. People can have iron deficiency but not have anemia. As iron deficiency worsens, anemia is more likely.

 

Why is it important in people with Down syndrome?

Iron deficiency and iron deficiency anemia can occur for many reasons in people with Down syndrome. One reason is celiac disease, which is more common in people with Down syndrome. Feeding challenges in some children with Down syndrome also can contribute. There are mixed data on how common iron deficiency is in people with Down syndrome compared to people without Down syndrome.

A blood test called a complete blood count (CBC) is done to check for anemia. People with Down syndrome often have differences in their CBC test results compared to people without Down syndrome even when they don’t have anemia. A CBC may find anemia due to iron deficiency, but it may not find when a person has iron deficiency but does not have anemia.

 

What can I do at home to prevent iron deficiency?

Eat foods that have iron in them. Foods that are high in iron include meat, poultry, seafood, beans, nuts, and certain vegetables. See the Cleveland Clinic’s How to Add More Iron to Your Diet  article for more information about iron-rich foods, including vegetarian choices.

Iron from meat is generally better absorbed than iron from plants, but enough iron can be consumed with appropriate management of a vegetarian diet.

 

What are symptoms of iron deficiency?

• Mood changes

• Hearing loss

• Dry skin

• Changes of the tongue (soreness, swelling, color change, etc.)

• Inflammation at the corner of the mouth/lips

• Spoon-shaped nails (nails that are dipped or indented in the middle)

• Hair loss (iron deficiency is a rare cause of hair loss)

 

What are some of the additional symptoms related to anemia?

• Pale skin

• Fatigue

• Restless legs syndrome (an uncomfortable urge to move the legs during periods of inactivity that can disrupt sleep)

• Getting unusually tired when exercising

• Weakness

• Pica (a desire to eat non-food substances such as dirt, paper, and others)

In children with more serious symptoms of iron deficiency anemia, motor skills and cognitive development may be affected.

 

What are some of the causes of iron deficiency or iron deficiency anemia?

• Blood loss

  • A few causes include:

    • Trauma

    • Bleeding in the gastrointestinal tract

    • Menstrual bleeding

• Reduced iron absorption

  • A few examples include:

    • Celiac disease

    • Bariatric surgery (surgery for weight loss)

    • Not eating enough foods with iron

    • Eating foods that reduce iron absorption (for example, tannates (in tea) and foods high in calcium)

    • Certain medications

      • Medications that reduce stomach acid such as proton pump inhibitors, antacids, and histamine receptor blockers are examples of medications that can reduce iron absorption. These medications are used to treat conditions that can cause bleeding in the gastrointestinal tract so it can be difficult to delineate if it is the medication or the bleeding that has caused iron deficiency.

There are some additional causes of iron deficiency that are much less common that will not be discussed here.

 

How is someone evaluated for iron deficiency or iron deficiency anemia?

Iron deficiency and iron deficiency anemia are diagnosed by a variety of tests.

• CBC

  • Mean corpuscular volume (MCV) and mean corpuscular hemoglobin concentration (MCHC) are two measures included in a CBC. Low levels of MCV and MCHC can be signs of iron deficiency and iron deficiency anemia.

• Serum iron

  • This blood test measures the amount of iron in the blood. Iron deficiency can cause a low serum iron. However, there are also other causes of low serum iron.

• Total iron-binding capacity (TIBC)

  • This blood test measures how much transferrin is present in the blood. Transferrin is a protein that transports iron. In iron deficiency, the TIBC is typically high.

• Transferrin saturation

  • This value is found by dividing the iron level by the TIBC. A low percentage is found in iron deficiency.

• Ferritin

  • This blood test measures the amount of iron stored in the body. Ferritin is a better marker to assess for iron deficiency than the other blood tests. In iron deficiency, the ferritin is usually low.

• Reticulocyte count

  • This blood test measures how well the bone marrow makes and releases new red blood cells. In iron deficiency anemia, the bone marrow is not able to make enough red blood cells and the reticulocyte count is low.

Once iron deficiency or iron deficiency anemia are diagnosed, an assessment for underlying causes is important. Examples include testing for celiac disease, an assessment for heavy periods, and/or a gastrointestinal evaluation to assess for bleeding from the stomach or intestines. 

 

Additional testing in a person with Down syndrome

• A study in children with Down syndrome  found that the CBC (including hemoglobin, hematocrit, and other indices) often missed diagnosing iron deficiency. The study concluded that transferrin saturation was the best measure. Based on their findings, the recommendation was to screen for iron deficiency or iron deficiency anemia with a CBC, reticulocyte count, serum iron, TIBC, and serum ferritin concentration.

• Another study in children with Down syndrome  recommended that a CBC and ferritin be obtained routinely for children with Down syndrome over 1 year of age (rather than a hemoglobin alone). 

• The AAP Health Supervision for Children and Adolescents with Down Syndrome recommends screening for anemia/iron deficiency with a complete blood count (CBC) and either (1) a combination of ferritin and C-reactive protein (CRP) or (2) a combination of serum iron and TIBC. They recommend starting at 1 year of age and testing annually thereafter. 

The current GLOBAL Medical Care Guidelines for Adults with Down Syndrome do not have a recommendation for iron deficiency screening.

 

How are iron deficiency and iron deficiency anemia treated?

The treatment will depend on the cause.

• If celiac disease is found, a gluten-free diet will be recommended.

• If there is bleeding in the gastrointestinal tract, medications and/or other treatments may be recommended.

• A diet higher in iron may be recommended.

• An iron supplement may be ordered, usually in the form of iron tablets.