When Your Child Has Megaloblastic Anemia

Normal disk-shaped red blood cell and spherical white blood cell. Next to these are much larger red blood cell and white blood cell with megaloblastic anemia.

Megaloblastic anemia occurs when there are not enough healthy red blood cells (RBCs) in the body. RBCs are important because they contain a protein called hemoglobin. Hemoglobin allows the blood to carry oxygen to all parts of the body. A child with megaloblastic anemia may feel very tired or have less energy than normal. Without treatment, symptoms can become severe and cause health problems. Your child's healthcare provider can evaluate your child and discuss treatment options with you.

What causes megaloblastic anemia?

This condition is most commonly due to a lack of folate or vitamin B12. Possible causes of this include:

  • Too little folate or vitamin B12 in the diet (more common in children who are vegetarian, vegan, or drink only goat's milk)

  • Certain conditions that involve the digestive system, such as Crohn's disease or celiac disease, which can affect how well the body absorbs folate or vitamin B12

  • Certain medicines that can affect how well the body absorbs folate

  • Lack of a special protein in the stomach (called intrinsic factor) that helps the body absorb vitamin B12

  • Hypothyroidism, some blood cancers, and some blood cell disorders are less common causes of this disease

What are the symptoms?

Symptoms can range from mild to severe. Some children have no symptoms at all. If symptoms are present, they may include:

  • Pale skin

  • Crankiness

  • Weakness

  • Fatigue

  • Neurologic problems including trouble with balance, coordination, or memory

  • Digestive problems including nausea, vomiting, constipation, diarrhea, or loss of appetite

How is it diagnosed?

Your child will likely see a pediatric hematologist for diagnosis and treatment. This is a doctor who specializes in blood disorders (hematology). The doctor will examine your child and ask about your child’s symptoms, medicines, diet, and health history. Tests are also done. Most of the tests involve taking a blood sample from a vein in the arm or from a finger or heel. Tests may include:

  • Complete blood cell count (CBC). This measures the amounts of types of cells in the blood.

  • Blood smear. This checks the size and shape of blood cells. A drop of blood is looked at with a microscope. A stain is used to make parts of the blood cells easier to see. With megaloblastic anemia, both the RBCs and the WBCs are too large and may not have formed correctly.

  • Reticulocyte count. This measures the amount of new RBCs being made by the bone marrow.

  • Other blood tests. These are done to check the levels of folate and vitamin B12 in the body.

  • Bone marrow biopsy. If a diagnosis is not obvious from other testing, this may be done to test for less common causes of megaloblastic anemia.

How is it treated?

Treatment for megaloblastic anemia varies depending on the cause and severity of symptoms. The goal is to restore the amount of folate or vitamin B12 in the body to normal so the body can build healthy RBCs. Common treatments include:

  • Diet changes to increase the folate or vitamin B12 in your child's diet. Foods that are rich in B12 and folate include eggs, meat, fish, poultry, and milk. Ask your child's healthcare provider for more nutrition resources, if needed. He or she can also refer you to a nutritionist for more information.

  • Folate or vitamin B12 pills or injections (or both) prescribed by the healthcare provider for your child.

  • Medicines to help the body absorb more folate or vitamin B12.

What are the long-term concerns?

With treatment, most children with megaloblastic anemia can manage their condition. They can then be as active and independent as other children. Ongoing treatment with folate or vitamin B12 may be needed. Your child may need to see his or her healthcare provider regularly for routine tests and help in managing symptoms.