One Cause of Vitamin B12 Deficiency
Pernicious anemia is an autoimmune condition in which the body cant absorbvitamin B12correctly.
This leads to symptoms fromanemia(a reduced number of functioning red blood cells) and other problems.
The word pernicious means gradually harmful and damaging.
Ellen Lindner / Verywell
Historically, before we understood its role and had vitamin B12 treatments available, it was often fatal.
Pernicious anemia is also sometimes referred to as autoimmune gastritis or Biermers disease.
For example, mild fatigue might be an initial sign.
In extreme circumstances, it can cause significant problems with the nervous system and even death.
For example, they have a higher risk of havingtype 1 diabetes, autoimmune thyroid disease, and vitiligo.
These may cause additional, distinct symptoms.
Causes
The most common cause of pernicious anemia is autoimmune gastritis leading to vitamin B12 deficiency.
Rarely, there is a genetic or congenital cause.
There are also other conditions resulting in poor absorbtion or low vitamin B12.
Vitamin B12 is important for many different chemical reactions in the body.
It performs several important functions, including helping with the synthesis of DNA.
So, its not surprising that symptoms result when there isnt enough vitamin B12 in the body.
Vitamin B12 must be taken in through the diet through foods of animal origin.
In pernicious anemia, something affects the bodys ability to effectively make intrinsic factor.
Because of autoimmune gastritis (the underlying cause of pernicious anemia) the bodys immune system is abnormally activated.
Antibodies form against intrinsic factor and the cells that make it, causing inflammation in the stomach.
Researchers are still learning why this happens to some people.
The risk also increases with age.
This can be because of other situations, including ones that decrease effective absorption of vitamin B12.
This throw in is called congenital pernicious anemia or intrinsic factor deficiency.
Unlike the more common form, symptoms usually begin in childhood.
The medical history provides the starting point for diagnosis.
The clinician asks about recent symptoms, long-term medical issues, and other relevant topics.
A physical exam provides additional key initial information, like information about how the nervous system is functioning.
Basic laboratory studies can help point to possible deficiency of vitamin B12.
A test called acomplete blood count (CBC)can often provide some key clues.
For example, lowhemoglobinthe protein that carries oxygencan be a sign of anemia.
Potential blood tests might include:
Another older test, the Schilling test, is now rarely performed.
Pernicious anemia may be harder to detect in someone who is iron deficient.
Treatment
The treatment of pernicious anemia is straightforward.
Affected people must take vitamin B12 to remedy their deficiency.
Taking vitamin B12 orally is another option, although this is not recommended for people with serious neurological symptoms.
In either case, you will need to start with a higher and/or more frequent dose.
This can help ensure that any potential cancer could be detected and treated promptly.
Overall, its important to get long-term follow-up.
Your practitioner can confirm you are still responding well to therapy and check for signs of related autoimmune disease.
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