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- Pernicious anemia facts
- What is pernicious anemia?
- What is megaloblastic anemia?
- What causes pernicious anemia?
- Is pernicious anemia the same as vitamin B-12 deficiency anemia?
- What are the symptoms of vitamin B-12 deficiency/ pernicious anemia?
- What kinds of doctors treat pernicious anemia?
- How is pernicious anemia/vitamin B-12 deficiency diagnosed?
- What is the treatment for pernicious anemia and vitamin B-12 deficiency?
- Can pernicious anemia/ vitamin B-12 deficiency be prevented?
- What is the prognosis for pernicious anemia/ vitamin B-12 deficiency?
What is pernicious anemia?
Anemia is a condition in which the body does not have a sufficient number of red blood cells or hemoglobin. Hemoglobin is present within red blood cells and is important for carrying oxygen to all tissues of the body. In males, anemia is typically defined as hemoglobin level of less than 13.5 gram/100ml, while in women, a hemoglobin level of less than 12.0 gram/100ml is considered to be indicative of anemia. These definitions may vary slightly depending on the source and the laboratory reference used. Pernicious is a term that means destructive, injurious or deadly.
Anemia can result from disruptions in the production of red blood cells or hemoglobin as well as from an increased destruction of red blood cells or loss of blood.
Pernicious anemia is a disease where large, immature, nucleated cells (megaloblasts, which are forerunners of red blood cells) circulate in the blood, and do not function as blood cells; it is a disease caused by impaired uptake of vitamin B-12 due to the lack of intrinsic factor (IF) in the gastric mucosa. It was termed "pernicious" because before it was learned that vitamin B-12 could treat the anemia, most people that developed the disease died from it.
Pernicious anemia is due to an inability to absorb vitamin B-12 (also known as cobalamin or Cbl) from the gastrointestinal tract. Humans get vitamin B-12 from animal products; both meat and dairy products are dietary sources of vitamin B-12. The body is able to store vitamin B-12 for a long time, so inadequate dietary intake must persist for years before a true deficiency of vitamin B-12 is reached. Therefore, the symptoms of pernicious anemia usually do not appear for years. While pernicious anemia is most commonly diagnosed in adults with an average age of 60, a rare, congenital (inborn) type of pernicious anemia has been described.
As with other causes of anemia, symptoms related to decreased oxygen-carrying capacity of the blood can include tiredness and shortness of breath. Vitamin B-12 deficiency also interferes with the function of the nervous system, and symptoms due to nervous system damage may be apparent even before the anemia is discovered.
Pernicious anemia is most common in Caucasian persons of northern European ancestry than in other racial groups. Pernicious anemia also is termed Biermer's or Addison's anemia.