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Megaloblastic Anemia in Children

What is megaloblastic anemia in children?

Anemia is a problem in which there are not enough red blood cells or hemoglobin. Hemoglobin is the part of red blood cells that carries oxygen throughout the body. In megaloblastic anemia, the bone marrow, where the cells are formed, makes fewer cells. And the cells that are formed don’t live as long as normal. The red blood cells:

  • Are too large

  • May be abnormally shaped

What causes megaloblastic anemia in a child?

There are many causes of megaloblastic anemia. The most common cause in children is lack of folic acid or vitamin B-12. Other causes include:

  • Digestive diseases. These include celiac disease, chronic infectious enteritis, and enteroenteric fistulas. Past surgery on the stomach or intestines may make it harder to absorb B-12 or folate. Pernicious anemia is a type of megaloblastic anemia. It’s caused when the body can't absorb vitamin B-12. A substance called intrinsic factor is normally made in the stomach. This substance helps the body absorb B-12. A person with pernicious anemia does not have enough of this substance.

  • Inherited congenital folate malabsorption. A genetic problem in which infants can’t absorb folic acid.

  • Medicines. Certain medicines, like those that prevent seizures, can interfere with how folic acid is absorbed.

  • Diet. Certain restrictive diets can lead to low levels of folate or B-12 because the child does not get enough of these nutrients.

What are the symptoms of megaloblastic anemia in a child?

These are some of the symptoms linked with megaloblastic anemia:

  • Pale or yellow skin

  • Fast heartbeat

  • Shortness of breath

  • Lack of energy, feeling tired

  • Decreased appetite

  • Irritability or fussiness

  • Hair color changes (rare)

  • Stomach upsets, nausea, diarrhea, gas, constipation

  • Trouble walking

  • Numbness or tingling in hands and feet

  • Smooth and sore tongue

  • Weak muscles

The symptoms of megaloblastic anemia may look like other conditions or health problems. Always check with your child's healthcare provider for a diagnosis.

How is megaloblastic anemia diagnosed in a child?

The healthcare provider will ask about your child’s symptoms and health history. They will give your child a physical exam. Your child may also have tests, such as:

  • Hemoglobin and hematocrit. This is often the first screening test for anemia in children. It measures the amount of hemoglobin and red blood cells in the blood. 

  • Complete blood count (CBC).  A complete blood count checks the red blood cells, white blood cells, blood clotting cells (platelets), and sometimes, young red blood cells (reticulocytes). It includes hemoglobin and hematocrit and more details about the red blood cells. 

  • Peripheral smear. A small sample of blood is examined under a microscope. Blood cells are checked to see if they look normal or not. 

  • Other blood tests. For example, your child may need bilirubin or other liver tests, folate and B-12 blood tests, and iron tests. 

Rarely, a bone marrow aspiration, biopsy, or both may be done to look at the number, size, and maturity of blood cells and abnormal cells.

How is megaloblastic anemia treated in a child?

Treatment will depend on the specific cause of the anemia, your child’s symptoms, age, and general health. It will also depend on how severe the condition is.

Your child's healthcare provider may refer you to a hematologist. This is an expert in blood disorders. If the anemia is caused by a digestive tract problem, it may need to be treated first. Your child's provider may also refer you to a gastroenterologist for this reason. This is an expert in digestive system problems. 

Most children with megaloblastic anemia are given B-12 or folic acid supplements. Vitamin B-12 supplements are best absorbed when given by injection. Folic acid supplements are given by mouth.

Foods that have natural folate include:

  • Oranges, orange juice

  • Dark green and leafy vegetables

  • Liver

  • Dairy products

  • Eggs

  • Meat

  • Brussels sprouts

  • Wheat germ

  • Beans, peas, lentils, nuts

Cereals, breads, pastas, and rice are fortified with folic acid.

Meat and dairy products have the most vitamin B-12. Other foods such as cereal may also be fortified with B-12.

Your child may need blood transfusions if it's a severe case.

What are possible complications of megaloblastic anemia in a child?

In general, anemia may cause:

  • Problems with growth and development

  • Fatigue

  • Poor exercise tolerance

  • An enlarged heart or heart failure, if the anemia is severe

When should I call my child's healthcare provider?

Call your child's healthcare provider if your child has decreased energy, increased tiredness, or other symptoms of anemia.

Key points about megaloblastic anemia in children

  • In megaloblastic anemia, there is a decrease in red blood cells. The cells are too large and may be abnormally shaped.

  • Having too little of the vitamins folic acid or B-12 are common causes of megaloblastic anemia.

  • The symptoms of megaloblastic anemia are like other types of anemia, such as tiredness and pale skin.

  • Megaloblastic anemia from vitamin deficiencies is treated by taking folate or B-12 supplements and eating more foods with these vitamins. 

Next steps

Tips to help you get the most from a visit to your child’s healthcare provider:

  • Know the reason for the visit and what you want to happen.

  • Before your visit, write down questions you want answered.

  • At the visit, write down the name of a new diagnosis, and any new medicines, treatments, or tests. Also write down any new instructions your provider gives you for your child.

  • Know why a new medicine or treatment is prescribed and how it will help your child. Also know what the side effects are.

  • Ask if your child’s condition can be treated in other ways.

  • Know why a test or procedure is recommended and what the results could mean.

  • Know what to expect if your child does not take the medicine or have the test or procedure.

  • If your child has a follow-up appointment, write down the date, time, and purpose for that visit.

  • Know how you can contact your child’s provider after office hours. This is important if your child becomes ill and you have questions or need advice.

Online Medical Reviewer: Dan Brennan MD
Online Medical Reviewer: Jessica Gotwals RN BSN MPH
Online Medical Reviewer: Liora C Adler MD
Date Last Reviewed: 1/1/2023
© 2000-2024 The StayWell Company, LLC. All rights reserved. This information is not intended as a substitute for professional medical care. Always follow your healthcare professional's instructions.