What is pernicious anemia?

A form of ANEMIA caused either by a dietary deficiency of VITAMIN B12 or by inadequate B12 absorption. It is characterized by quite large red blood cells (macrocytic) that are overloaded in the hemoglobin (hyperchromic). Low vitamin B12 consumption is a concern for strict VEGETARIANS who avoid meat and meat products. Pernicious anemia is also caused by inadequate vitamin B12 uptake. Normally, the gastric lining secretes a PROTEIN called INTRINSIC FACTOR that’s needed to specifically bind vitamin B12. Because this protein is required for vitamin B12 absorption by the intestine, inadequate intrinsic factor production, even with adequate dietary B12, can cause pernicious anemia.
Pernicious anemia affects the nervous system as well as the blood. Symptoms include memory loss, weakness, personality and mood swings, and numbness and tingling in the hands and feet. If this anemia continues unchecked, nerve damage may be irreversible. Pernicious anemia is most common in males between the ages of 40 and 65 years who have a family history of the condition. Treatment for intrinsic factor defect involves vitamin B12 injections. Oral doses of vitamin B12 can remedy dietary deficiencies when intrinsic factor production is normal.