Macrocytic achylic anemia; Congenital pernicious anemia; Juvenile pernicious anemia; Vitamin B12 deficiency (malabsorption)
Definition of Pernicious anemia
Pernicious anemia is a decrease in red blood cells that occurs when the body cannot properly absorb vitamin B12 from the gastrointestinal tract. Vitamin B12 is necessary for the proper development of red blood cells.
Causes, incidence, and risk factors
The body needs vitamin B12 to make red blood cells. To provide vitamin B12 to your blood cells, you need to eat enough foods containing vitamin B12, such as meat, poultry, shellfish, eggs, and dairy products.
People with mild anemia may have no symptoms or very mild symptoms. More typical symptoms of vitamin B12 deficiency anemia include:
Signs and tests
Tests that may used to diagnose or monitor pernicious anemia include:
Monthly vitamin B12 injections are prescribed to correct the vitamin B12 deficiency. This therapy treats the anemia and may correct the neurological complications if taken early enough. In people with a severe deficiency, the injections are given more often at first.
The outcome is usually excellent with treatment.
David Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine; and Yi-Bin Chen, MD, Leukemia/Bone Marrow Transplant Program, Massachusetts General Hospital. Aslo reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc. – 11/23/2008