pernicious anemia

A reduction in the number of circulating red blood cells. When a person has pernicious anemia, certain cells lining the stomach fail to produce enough intrinsic factor, a substance needed to insure intestinal absorption of vitamin B12. This vitamin is necessary for the normal production of red blood cells. Symptoms include weakness, fatigue, numbness and tingling of the hands or feet, as well as degeneration of the central nervous system.