Folate-deficiency anemia

• Causes, incidence, and risk factors

  Folate, also called folic acid, is necessary for red blood cell formation and growth. You can get folate by eating green leafy vegetables and liver. Because folate is not stored in the body in large amounts, you need to get a continual supply of this vitamin through diet to maintain normal levels.

  In folate-deficiency anemia, the red cells are abnormally large. These large cells are called megalocytes, or megaloblasts in the bone marrow. That is why this anemia can also be called megaloblastic anemia.

  Causes of this anemia are:

  • Certain medications (such as phenytoin [Dilantin], alcohol, methotrexate, sulfasalazine, triamterene, pyrimethamine, trimethoprim-sulfamethoxazole, and barbiturates)
  • Chronic alcoholism
  • Crohn's disease, celiac disease, infection with the fish tapeworm, or other problems that make it difficult for your body to digest foods
  • Poor dietary intake of folic acid
  • Surgeries that remove certain parts of your stomach or small intestine, such as some weight-loss surgeries

  In the third trimester of pregnancy, a woman may have a deficiency due to an increased need for folic acid. Hemolytic anemia can also cause a deficiency due to increased red blood cell destruction and increased need.

  Risk factors include:

  • Alcoholism (which interferes with the absorption of folate)
  • Eating overcooked food
  • Poor diet (often seen in the poor, the elderly, and people who do not eat fresh fruits or vegetables)
  • Pregnancy

  The disease occurs in about 4 out of 100,000 people.

• Symptoms
  • Fatigue
  • Headache
  • Pallor
  • Sore mouth and tongue
• Signs and tests
  • Bone marrow examination (rarely necessary)
  • Complete blood count (CBC)
  • Red blood cell folate level
• Treatment

  The goal is to identify and treat the cause of the folate deficiency.

  Folic acid supplements may be given by mouth (oral) or through a vein (intravenous) on a short-term basis until the anemia has been corrected. In the case of poor absorption by the intestine -- replacement therapy may be lifelong.

  Dietary treatment consists of increasing the intake of green, leafy vegetables and citrus fruits.

• Expectations (prognosis)

  Anemia usually responds well to treatment within 2 months.

• Complications

  Symptoms of anemia can cause discomfort. In pregnant women, folate deficiency has been associated with neural tube or spinal defects (such as spina bifida) in the infant.

  Other, more severe complications may include:

  • Curly graying hair
  • Increased skin color (pigment)
  • Infertility
  • Worsening of heart disease or heart failure
• Calling your health care provider

  Call for an appointment with your health care provider if you have symptoms of folate deficiency anemia.

• Prevention

  Good dietary intake of folate in high-risk individuals, and folic acid supplementation during pregnancy may help prevent this anemia.

• References

  Antony AC. Megoblastic anemias. In: Hoffman R, Benz EJ, Shattil SS, et al., eds. Hematology: Basic Principles and Practice. 5th ed. Philadelphia, Pa: Elsevier Churchill Livingstone; 2008:chap 39.

  Kaferie J, Strzoda CE. Evaluation of macrocytosis. Am Fam Physician. 2009;79:203-208.

Review Date: 1/31/2010

Reviewed By: Yi-Bin Chen, MD, Leukemia/Bone Marrow Transplant Program, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.