What is an iron overload evaluation?
An iron overload evaluation is a series of tests and assessments that check the iron in your child’s body. The care team needs to make sure that iron buildup does not harm your child.
Iron is an essential mineral that our bodies need to work properly. But too much iron in the body can cause iron overload. Another name for this condition is hemochromatosis. Too much iron in the body can damage vital organs such as the liver, heart, and pancreas.
Iron overload may be caused by a gene change (mutation) passed down in families. Other causes of iron overload include frequent blood transfusions, anemia, thalassemia, and liver disease.
How an iron overload evaluation works
The care team uses many different tests for this evaluation. They will look at the results of all the tests together to see if your child’s iron levels are too high.
If your child has had these tests before, the care team will compare the new results to the old ones. This helps them choose the best treatment plan for your child.
Getting ready for an iron overload evaluation
Before the evaluation, your care provider may give you specific instructions. Your child might need to fast (not eat or drink anything except water) before some of the tests. This helps make sure the results are accurate. Be sure to follow your care team’s instructions.
Your care team will also review any medicines your child takes. Some medicines can affect iron levels. If your child takes deferoxamine (Desferal®) or deferasirox to help their body get rid of iron, the care team will look for side effects of that medicine. If your child is already taking one of these drugs, they may need to keep taking it as prescribed. Be sure to follow your care team’s instructions.
What to expect during an iron overload evaluation
Before your child begins their iron overload evaluation, the care team will ask about their health history and perform a physical exam.
The care team will also measure your child’s vital signs, weight, and height. They may also do blood tests.
The iron overload evaluation will include various tests to get a complete picture of your child’s iron levels. Not every patient has every test. Your child’s care team will decide which ones are needed. Always ask if you have questions about the tests.
Iron overload diagnostic tests
Your child’s iron overload evaluation may include some of these diagnostic tests:
- CT scan: Your child may have a CT or CAT scan to look at the thickness of the bones. People who have too much iron can have thin bones that break easily. Calcium loss can be a side of effect of medication used to treat iron overload. Both CT and CAT scans are painless. Your care provider will compare the results of these scans to other bone density tests your child may have had.
- Echocardiogram (echo): This painless test is an ultrasound of the heart. The test measures the size of the heart and how well it works.
- EKG: An electrocardiogram (EKG) measures the electrical activity of the heart and its rhythm. Too much iron in the heart muscle can cause the heart to grow, work too hard, have irregular rhythms, or pump blood less effectively. Your child’s care team will compare these results to earlier tests if those are available.
- Genetic testing: Your care provider may order genetic tests if they think your child inherited iron overload.
- Liver biopsy: This test measures how much iron is in your child’s liver. The test also shows if any damage has been done to the liver by hepatitis or iron deposits. For a liver biopsy, your child will be given anesthesia. The provider takes a small sample of liver tissue in 1 of 2 ways: through a vein in the neck or with a needle through the abdomen (belly). Your care provider will decide which method is best. Your child will likely need to stay in the hospital all day so the care team can watch for any side effects of the procedure. Your child will probably not have an incision (cut) or stitches, but they may feel a little tired or sore. The care provider will compare the results of this biopsy to past results.
- MRI: This scan will show how much iron is in the liver and spleen.
- Nuclear medicine scan: During this scan, a dye is injected into your child’s veins. The medical team will use special scanning equipment to watch the blood flow through the heart to see how well it pumps.
- Ultrasound of the abdomen (belly): If your child has hepatitis, they will probably have this test to look at the size and shape of the organs in the abdomen, especially the liver.
- X-ray (chest and bone age): The bone age x-ray shows whether the bones are growing properly for your child’s age. People with too much iron sometimes have changes in growth patterns. A chest x-ray shows the size of the heart and the appearance of the lungs.
Iron overload specialty visits
The evaluation may also include the following appointments:
- Audiology visit: Audiology is the study of hearing. Anyone who uses deferoxamine or deferasirox may have changes in the nerves needed for hearing. Iron can also damage the hearing nerves.
- Endocrine specialist visit: These doctors specialize in the growth and hormones of children and adolescents. They will measure your child’s height and weight and ask questions about growth and development. They will look at your child’s blood test results to see if they have normal amounts of hormones for growth and development. Some children with too much iron have delayed growth, a delayed onset of puberty, or changes in insulin production and use (diabetes).
- Eye clinic visit: An eye doctor will examine your child’s eyes for any vision changes or changes to the structure of the eyes. People who take deferoxamine or deferasirox may have vision changes over time.
Iron overload lab tests
The care team will order lab tests as part of their iron overload evaluation. Your child may not need every test. Some of the results will be ready the same day. Others may take several days or weeks. Talk with your child’s care team about the results. Lab tests for iron overload include:
- Alpha fetoprotein: If your child has hepatitis C, the care team will test for alpha fetoprotein. This can be an early warning sign of liver cancer.
- Complete blood count (CBC): This blood test measures the number, size, and type of cells in the blood. From this test, the care team can learn the amount of hemoglobin your child has and decide whether they need a transfusion of blood or platelets.
- Chemistry panel: This blood test measures the amount of different chemicals and electrolytes in your child’s blood, such as sodium, potassium, or magnesium, or liver function tests.
- Coagulation (blood clotting) screen: The liver makes proteins that help the blood clot in an injury. The care team wants to make sure your child’s liver is making the right amount. This test measures the blood’s ability to clot. A member of the care team must use a needle to collect the blood sample, even if your child has a central line.
- Ferritin: Ferritin is an iron-storage protein made in the body. It usually corresponds to the total amount of iron stored all over the body.
- Free T4, TSH, PTH, FSH: All of these chemicals are hormones. Since iron overload can affect your child’s growth and development, this is one way the care team can measure their development.
- Hepatitis C PCR: If your child has hepatitis C, this test will measure the amount of hepatitis virus living in their body. The care team will watch how these viruses increase or decrease over time.
- Hepatitis panel / HIV screen: The care team screens every patient for these viruses. Rarely, people who have received blood transfusions have contracted 1 of these viruses. Hepatitis can damage the liver, the main organ of iron storage.
- 2-hour glucose and insulin test: The care team will ask you to note when your child had a big meal. Then, they will draw blood 2 hours after that meal. Some people with too much iron develop diabetes. This blood test tells how well your child’s body uses up its sugar with the hormone insulin, and whether your child is at risk for diabetes.
- Urine studies: The care team will ask to collect your child’s urine. This may be a single sample, or a 24-hour collection which asks to collect all your child’s urine (pee) for 24 hours. The lab will measure how much of several chemicals, such as iron, glucose, or protein, are in your child’s urine. They compare this amount to the amount in blood to see if the kidneys are filtering the blood well and removing harmful chemicals correctly.
After the iron overload evaluation
After the evaluation, your health care provider will review your child’s test results with you. If your child’s iron levels are too high, they may recommend treatments to reduce the levels. Common treatments for iron overload include:
- Therapeutic phlebotomy: This procedure involves regularly removing blood from your child’s body to lower iron levels. It is similar to donating blood and is a common treatment for iron overload.
- Chelation therapy: This treatment involves taking a medicine such as deferoxamine or deferasirox that binds to the excess iron in your child’s body, allowing it to be removed from the body through pee or poop.
- Changes in diet: Your care team may suggest changes to your child’s diet, such as avoiding foods high in iron or vitamin C (which increases iron absorption). A dietitian can help you know what diet changes may be needed.
Your child’s health care provider will let you know how often your child will need follow-up tests to monitor their iron levels. Be sure to follow your child’s treatment plan and attend all follow-up appointments.
Questions to ask your care team
