Megaloblastic anemia

Definition

Megaloblastic anemia is a blood disorder in which there is anemia with larger-than-normal red blood cells.

Alternative Names

Anemia - megaloblastic

Causes, incidence, and risk factors

Megaloblastic anemia is usually caused by a deficiency of folic acid or vitamin B12. Other causes are:

• Alcohol abuse
• Certain inherited disorders
• Drugs that affect DNA, such as chemotherapy drugs
• Leukemia
• Myelodysplastic syndrome
• Myelofibrosis

Risk factors relate to the causes.

See also: Pernicious anemia

Symptoms

• Change in skin color
• Diarrhea
• Headaches
• Loss of appetite
• Pale skin color
• Sore mouth and tongue
• Tingling and numbness of hands and feet
• Tiredness

Signs and tests

Examination of the nervous system may show:

• Abnormal reflexes
• Decreased sense of position
• Decreased sense of vibration
• Serum ferritin Tests include:

• Bone marrow examination
• Complete blood count
• Schilling test
• Serum B12 level
• Serum folate level
• Serum methylmalonic acid

Treatment

The first goal is to diagnose the cause of the anemia. The treatment depends on the cause. Anemias related to specific vitamin deficiencies are discussed separately.

Expectations (prognosis)

The outcome depends on the cause of the anemia.

Complications

Complications vary with the cause of the anemia.

Calling your health care provider

Call for an appointment with your health care provider if you develop symptoms of this condition.

Prevention

Getting enough vitamin B12 and folic acid is helpful.

References

Antony AC. Megoblastic anemias. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 170.