When Your Child Has Megaloblastic Anemia

June 17, 2017

When Your Child Has Megaloblastic Anemia



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


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

What are the symptoms?


  • Pale skin

  • Crankiness

  • Weakness

  • Fatigue

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


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:


  • 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.


  • 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?


  • 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.


June 17, 2017


Diagnosis and treatment of vitamin B12 and folate deficiency. UpToDate., Macrocytosis. UpToDate.

Reviewed By:  

Adler, Liora C., MD,Bass, Pat F. III, MD, MPH,Image reviewed by StayWell medical illustration team.