Overview

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
  • Not fully developed
  • Abnormally shaped

Causes

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. 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.

Symptoms

These are some of the symptoms of megaloblastic anemia:

  • Pale or yellow skin
  • Fast heart beat
  • Shortness of breath
  • Lack of energy, feeling tired
  • Decreased appetite
  • Irritability or fussiness
  • Hair color changes
  • 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 medical problems. Always check with your child's doctor for a diagnosis.

Diagnosis

The healthcare provider will ask about your child’s symptoms and health history. He or she 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, or 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. 

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

Your child may also need a barium study or other imaging tests of the digestive system.

Treatment

Treatment will depend on 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. He or she 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
  • Barley
  • Sprouts
  • Wheat germ
  • Beans, peas, lentils
  • Peanuts

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

Meat and dairy products have the most vitamin B-12.

Complications

In general, anemia may cause:

  • Problems with growth and development
  • An enlarged heart, heart failure

Megaloblastic anemia can also cause problems with the nervous system. 

When to Call a Healthcare Provider

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

Key Points

  • In megaloblastic anemia, there is a decrease in red blood cells. The cells are too large, not fully developed, and 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), and there are also nervous system symptoms.
  • Megaloblastic anemia from vitamin deficiencies is treated with 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.