Intrinsic Factor Blocking Antibody Blood Test
The Intrinsic Factor Blocking Antibody Blood Test may be used in determining the cause of a vitamin B12 deficiency and to confirm a diagnosis of pernicious anemia.
Description
An intrinsic factor antibody (IF antibody) test may be used to help determine the cause of a vitamin B12 deficiency and to confirm a diagnosis of pernicious anemia.
It may be ordered when a person has a vitamin B12 deficiency and when pernicious anemia is suspected, as when a person has signs and symptoms such as:
- Paleness
- Weakness, fatigue
- Numbness and tingling in the feet and/or hands
- Larger than normal red blood cells (RBCs); sometimes large RBCs are detected before the other signs and symptoms emerge, for example, with a complete blood count (CBC) during routine testing for a health examination.
These findings usually prompt vitamin B12 and folate testing and may lead to methylmalonic acid testing (an early indicator of vitamin B12 deficiency).
When a person has a decreased vitamin B12 level and increased methylmalonic acid and homocysteine levels, an IF antibody test is typically ordered.