Parietal Cell Antibody, ELISA

The Parietal Cell Antibody, ELISA test contains 1 test with 1 biomarker.

Brief Description: The Parietal Cell Antibody, Enzyme-Linked Immunosorbent Assay (ELISA) test is a medical laboratory examination that measures the presence of antibodies against parietal cells in the stomach. This test is crucial in diagnosing autoimmune conditions that affect the stomach lining and the production of intrinsic factor, such as autoimmune gastritis and pernicious anemia.

Also Known As: Gastric Parietal Cell Antibody Test, Anti-Parietal Cell Antibody Test, Anti-GPA Test, AGPA Test, APCA Test

Collection Method: Blood Draw

Specimen Type: Serum

Test Preparation: No preparation required

When is a Parietal Cell Antibody test ordered?

Because the parietal cell antibody test is less accurate than the intrinsic factor antibody test, it is not usually requested. When a person exhibits symptoms that point to a vitamin B12 deficiency and when pernicious anemia is suspected, it may be prescribed.

Testing for vitamin B12, folate, methylmalonic acid, and homocysteine are frequently prompted by results from parietal cell antibody tests.

When a person has a decreased vitamin B12 level and elevated levels of methylmalonic acid and homocysteine, follow-up tests such as an intrinsic factor antibody test and a parietal cell antibody test may be prescribed.

What does a Parietal Cell Antibody test check for?

Autoantibodies, which are proteins created by the immune system and wrongly target a particular class of specialized cells that line the stomach wall, include parietal cell antibodies. This test finds these antibodies in the blood, which aids in the identification of pernicious anemia.

When the body's immune system attacks its own tissues and produces antibodies against the parietal cells and/or intrinsic factor, pernicious anemia can develop.

Parietal cells are specialized stomach cells that produce intrinsic factor and acid to aid in meal digestion.

Vitamin B12 must have intrinsic factor in order to be absorbed from diet.

Vitamin B12 is released from food during digestion by the stomach acids made by parietal cells, who then combine it with intrinsic factor to form a complex. This complex's production enables vitamin B12 absorption in the small intestine. Vitamin B12 is crucial for the synthesis of red blood cells in addition to its responsibilities in the brain and nervous system.

When the immune system of the body mistakenly attacks its own tissues and produces antibodies against intrinsic factor and/or parietal cells, it can lead to inflammation and gradually harm parietal cells. The generation or operation of intrinsic factor may be interfered with by this autoimmune disease, known as autoimmune atrophic gastritis.

Vitamin B12 is generally not absorbed when there is insufficient intrinsic factor, which results in a vitamin B12 deficit. Megaloblastic anemia, which is characterized by the formation of fewer but larger red blood cells, can be brought on by vitamin B12 deficiency. Additionally, a lack of vitamin B12 can cause signs and symptoms of nerve damage, such as numbness and tingling that first appear in the hands and feet, muscle weakness, sluggish reflexes, loss of balance, and shaky gait. Megaloblastic anemia and vitamin B12 deficiency can be brought on by other conditions. Pernicious anemia is the name for the condition when it results from a deficiency of intrinsic factor. Neutrophils and platelets may be less plentiful, in addition to anemia.

In order to identify pernicious anemia, the tests for parietal cell and/or intrinsic factor antibodies may be combined with a number of other procedures, such as complete blood count and blood smear.

Lab tests often ordered with a Parietal Cell Antibody test:

When a Parietal Cell Antibody test is ordered, it's typically part of a broader evaluation to understand the underlying causes of anemia, gastric issues, and potential autoimmune disorders. Here are some tests commonly ordered alongside it:

1. Vitamin B12 Level:

   • Purpose: To measure the amount of vitamin B12 in the blood.
   • Why Is It Ordered: To assess for vitamin B12 deficiency, which can result from pernicious anemia due to the loss of intrinsic factor production.

2. Complete Blood Count (CBC):

   • Purpose: To evaluate overall blood health, including red blood cells, white blood cells, and platelets.
   • Why Is It Ordered: To check for signs of anemia, particularly megaloblastic anemia, which is associated with vitamin B12 deficiency.

3. Intrinsic Factor Antibody Test:

   • Purpose: To detect antibodies against intrinsic factor.
   • Why Is It Ordered: To help diagnose pernicious anemia, as these antibodies can directly lead to B12 deficiency by interfering with intrinsic factor function.

4. Iron Studies:

   • Purpose: To evaluate iron status.
   • Why Is It Ordered: To assess for iron deficiency anemia and differentiate it from anemia caused by B12 deficiency.

5. Reticulocyte Count:

   • Purpose: To measure the number of reticulocytes (immature red blood cells) in the blood.
   • Why Is It Ordered: To assess bone marrow response, especially in the context of anemia.

6. Folate Level:

   • Purpose: To measure the level of folate in the blood.
   • Why Is It Ordered: To assess for folate deficiency, which can also cause megaloblastic anemia and can coexist with B12 deficiency.

7. Gastrin Level:

   • Purpose: To measure the level of gastrin, a hormone that stimulates acid production in the stomach.
   • Why Is It Ordered: Elevated gastrin levels can be indicative of chronic atrophic gastritis, which is often associated with autoantibodies against parietal cells.

8. Anti-Endomysial and Tissue Transglutaminase Antibodies:

   • Purpose: To screen for celiac disease.
   • Why Is It Ordered: To rule out celiac disease as a cause of malabsorption, particularly if there are gastrointestinal symptoms.

These tests, when ordered alongside a Parietal Cell Antibody test, provide a comprehensive evaluation of potential autoimmune gastritis, pernicious anemia, and other related conditions. They are crucial for diagnosing the underlying causes of anemia, assessing gastric health, and planning appropriate treatment. The specific combination of tests will depend on the individual’s symptoms, clinical presentation, and medical history.

Conditions where a Parietal Cell Antibody test is recommended:

1. Autoimmune Gastritis: This condition occurs when the immune system attacks the parietal cells in the stomach lining, leading to reduced stomach acid production and intrinsic factor secretion. This can result in digestive problems and anemia.
2. Pernicious Anemia: Pernicious anemia is often linked to autoimmune gastritis. The absence of intrinsic factor due to immune attack leads to an inability to absorb vitamin B12, causing anemia and other related symptoms.

How does my health care provider use a Parietal Cell Antibody test?

To help identify the root cause of a vitamin B12 shortage and to support the diagnosis of pernicious anemia, a parietal cell antibody test may be utilized in conjunction with or after an intrinsic factor antibody test.

It is typically done as a follow-up test after other lab tests, methylmalonic acid, vitamin B12, or a complete blood count with a blood smear examination, identify a person as having a vitamin B12 deficiency and any accompanying megaloblastic anemia and/or neuropathy.

What do my Parietal Cell Antibody test results mean?

When making a diagnosis, the results of this test are frequently compared to those from other laboratory tests.

A person is more likely to have pernicious anemia if they have decreased vitamin B12 levels, elevated levels of methylmalonic acid and homocysteine, and positive test results for intrinsic factor antibodies and/or parietal cell antibodies.

The absence of pernicious anemia is not always indicated by a negative test result. At least 10% of those affected won't have antibodies to parietal cells.

Antibodies against parietal cells are less focused than those against intrinsic factors. Parietal cell antibodies are present in about 90% of people who have pernicious anemia.

Most Common Questions About the Parietal Cell Antibody, ELISA test:

Test Purpose and Indications

What is the purpose of the Parietal Cell Antibody, ELISA test?

The Parietal Cell Antibody, ELISA test is used to detect the presence of autoantibodies against parietal cells in the stomach. Parietal cells produce intrinsic factor and hydrochloric acid, essential for vitamin B12 absorption. The presence of these antibodies suggests an autoimmune reaction against the stomach's parietal cells, which can be indicative of conditions such as pernicious anemia.

Why might a doctor order the Parietal Cell Antibody, ELISA test?

A doctor might order the Parietal Cell Antibody, ELISA test if a patient shows symptoms of vitamin B12 deficiency, unexplained anemia, or other clinical signs that raise suspicion of autoimmune gastritis or pernicious anemia. This test helps in confirming or ruling out the autoimmune etiology behind these conditions.

Comparison to Other Tests

How does the Parietal Cell Antibody, ELISA test differ from the Intrinsic Factor Antibody test?

Both the Parietal Cell Antibody, ELISA test and the Intrinsic Factor Antibody test are used in the diagnosis of pernicious anemia. While the former detects antibodies against parietal cells, the latter detects antibodies against intrinsic factor. Antibodies against intrinsic factor directly interfere with vitamin B12 absorption in the ileum, making their detection more specific for pernicious anemia than parietal cell antibodies.

Test Interpretation

What does a positive result in the Parietal Cell Antibody, ELISA test indicate?

A positive result indicates the presence of antibodies against parietal cells. While this can be suggestive of conditions like pernicious anemia, it's not exclusively diagnostic for it. Other autoimmune conditions, as well as age-related changes, might lead to the presence of these antibodies. Clinical correlation and additional testing are usually needed.

Can you have a negative Parietal Cell Antibody, ELISA test and still have pernicious anemia?

Yes, it's possible. The Parietal Cell Antibody test is not as specific as the Intrinsic Factor Antibody test for pernicious anemia. A patient may not have detectable levels of parietal cell antibodies but still have the disease. If clinical suspicion remains high, further testing, especially for intrinsic factor antibodies, might be warranted.

General Information

Is there any special preparation a patient should undertake before the Parietal Cell Antibody, ELISA test?

No specific preparation is typically required for this test. However, patients should always inform their healthcare provider of any medications or supplements they're taking, as some substances could potentially interfere with test results.

How are results typically expressed for the Parietal Cell Antibody, ELISA test?

Results for the Parietal Cell Antibody, ELISA test are usually given as positive or negative. Some labs may provide a titer or measure of antibody levels, but the presence or absence of the antibodies is the primary diagnostic information.

How often might a patient need to repeat the Parietal Cell Antibody, ELISA test?

Repeat testing isn't typically done unless there's a change in clinical presentation or if it's being used to monitor the progression of a known autoimmune condition. However, the frequency would be determined on a case-by-case basis by the healthcare provider.

We advise having your results reviewed by a licensed medical healthcare professional for proper interpretation of your results.