Is pernicious anemia the same as vitamin B-12 deficiency anemia?
No, pernicious anemia is one form of vitamin B-12 deficiency that results from the autoimmune process described previously. However, other causes of vitamin B-12 deficiency also can produce the same signs and symptoms as pernicious anemia. Other potential causes of vitamin B-12 deficiency include surgical removal of the stomach or a portion of the stomach (total or partial gastrectomy), other gastrointestinal diseases such as celiac disease or Crohn's disease, infections of the gastrointestinal tract, longstanding use of acid-reducing medications, and poor nutrition.
What are the symptoms of vitamin B-12 deficiency/ pernicious anemia?
As discussed previously, true pernicious anemia results from an autoimmune condition that impairs absorption of dietary vitamin B-12, resulting in vitamin B-12 deficiency. Vitamin B-12 deficiency of any cause, including pernicious anemia, will result in anemia and neurologic symptoms. Because the body has large stores of vitamin B-12, a deficiency takes many years to establish.
Vitamin B-12 deficiency affects the nervous system, leading to a variety of symptoms. Sometimes, these may be apparent before symptoms related to the anemia. Neurological symptoms vary and may be nonspecific (meaning that these are symptoms that can be caused by a number of different conditions). Feelings of numbness, tingling, weakness, lack of coordination, clumsiness, impaired memory, and personality changes can all occur. Both sides of the body are usually affected, and the legs are typically more affected than the arms. A severe deficiency can result in more serious neurological symptoms, including severe weakness, spasticity, paraplegia, and fecal and urinary incontinence.
Symptoms of anemia are due to the reduced oxygen-carrying capacity of the blood. Shortness of breath, fatigue, dizziness, and pale skin can all occur with anemia. In anemia, the heart is placed under stress since it has to work harder to deliver enough oxygen to body tissues. This can result in heart murmurs, fast heartbeats, arrhythmias, an enlarged heart (cardiomegaly), or even heart failure. It is important to note that not all people who have vitamin B-12 deficiency and neurological symptoms also will have anemia.
A deficiency of vitamin B-12 also can alter the surface of the tongue, making it appear shiny or smooth.
Finally, sometimes pernicious anemia is diagnosed in a patient with no symptoms. In these cases, it is usually found incidentally when blood tests are ordered for another reason.