The Intrinsic Factor Blocking Antibody test contains 1 test with 1 biomarker.
Description: The Intrinsic Factor Blocking antibody test is a blood test used to detect antibodies to Intrinsic Factor, a protein complex created by your stomach lining to help your body absorb Vitamin B12.
Also Known As: Intrinsic Factor Antibody test, IF Antibody Test, IF Antibody Type 1 Test, IF Antibody Type 2 Test,
Collection Method: Blood Draw
Specimen Type: Serum
Test Preparation: No preparation required
When is an Intrinsic Factor Blocking Antibody test ordered?
It is uncommon to order the intrinsic factor antibody test. When a person has symptoms of pernicious anemia with a vitamin B12 deficiency, such as when they exhibit the following signs and symptoms:
- weakness, exhaustion
- tingling and numbness in the hands and/or feet
- larger-than-normal red blood cells; occasionally, large RBCs are found before the other symptoms become apparent, for example, during a routine complete blood count test for a health examination.
Testing for vitamin B12, folate, and methylmalonic acid is typically prompted by these findings.
An IF antibody test is often requested when a person's vitamin B12 level is low and their levels of homocysteine and methylmalonic acid are elevated.
What does an Intrinsic Factor Blocking Antibody test check for?
Intrinsic factor antibodies are immune system-produced proteins linked to pernicious anemia. This examination finds blood-circulating intrinsic factor antibodies.
A type of specialized stomach wall cell known as parietal cells produces the protein known as intrinsic factor. Stomach acids release vitamin B12 from food during digestion, and it then binds with intrinsic factor to create a complex. For vitamin B12 to be absorbed in the small intestine, this complex must first form.
Vitamin B12 is crucial for the synthesis of red blood cells in addition to its responsibilities in the brain and nervous system. Vitamin B12 is generally not absorbed if there is insufficient intrinsic factor, which prevents the body from producing enough healthy red blood cells and results in anemia. The amount of neutrophils and platelets may fall in addition to anemia.
Pernicious anemia is anemia brought on by a deficiency of intrinsic factor. This disorder is primarily autoimmune in nature and results from the body's immune system producing antibodies against parietal cells and/or the intrinsic factor. These antibodies have the potential to harm parietal cells, obstruct the generation of intrinsic factor, or stop intrinsic factor from performing its biological role.
The laboratory can check for two different IF antibodies:
The most common test is for intrinsic factor blocking antibody, because it is more specific for pernicious anemia.
Antibody that binds intrinsic factors prevents the absorption of the combination of intrinsic factors and vitamin B12
Lab tests often ordered with an Intrinsic Factor Blocking Antibody test:
- Vitamin B12
- Methylmalonic Acid
- Parietal Cell Antibody
- Complete Blood Count
Conditions where an Intrinsic Factor Blocking Antibody test is recommended:
- Vitamin B12 and Folate Deficiencies
- Autoimmune Disease
How does my health care provider use an Intrinsic Factor Blocking Antibody test?
A vitamin B12 deficiency's underlying cause and the presence of pernicious anemia can both be determined with the use of an intrinsic factor antibody test.
Lack of intrinsic factor results in vitamin B12 insufficiency, which is the cause of pernicious anemia. The primary cause of this illness is when the body's immune system creates antibodies against its own tissues and targets the parietal cells or intrinsic factor. These antibodies have the potential to harm parietal cells, obstruct the generation of intrinsic factor, or stop intrinsic factor from performing its biological role. Vitamin B12 and intrinsic factor combine to generate a compound that facilitates absorption in the small intestine.
In most cases, IF antibody testing is utilized as a follow-up procedure after other laboratory tests, including as a vitamin B12 test, a methylmalonic acid test, and a complete blood count, have determined that a person has a vitamin B12 deficiency with accompanying anemia and/or neuropathy.
It can help establish a diagnosis when combined with a test for antibodies against parietal cells.
There are two IF antibodies that could be examined:
anti-intrinsic factor antibody that prevents vitamin B12 from attaching to intrinsic factor. This is the one that is typically examined since it is more specific for pernicious anemia.
Antibody that binds to or precipitates intrinsic factors and prevents the small intestine from absorbing the intrinsic factor-vitamin B12 combination.
What do my Intrinsic Factor Blocking Antibody test results mean?
When making a diagnosis, the results of other laboratory tests are frequently combined with the results of intrinsic factor antibody tests. It is most likely that someone has pernicious anemia if they have elevated IF antibodies, elevated methylmalonic acid and homocysteine levels, and low vitamin B12 levels.
The absence of pernicious anemia is not always indicated by a negative test result. Up to 50% of persons who are impacted won't have IF antibodies. In the absence of them, the doctor may request a parietal cell antibody test to aid in making the diagnosis. Antibodies against parietal cells are less focused than IF antibodies. About 90% of people with pernicious anemia have them, but they can also be found in a wide range of other diseases and in approximately 10% of the general public.
We advise having your results reviewed by a licensed medical healthcare professional for proper interpretation of your results.