Intrinsic factor antibodies
CPT4 code
Name of the Procedure:
Intrinsic Factor Antibodies Test
Summary
The intrinsic factor antibodies test is a blood test that measures the presence of antibodies targeting intrinsic factor, a protein required for vitamin B12 absorption from the intestines.
Purpose
This test helps in diagnosing pernicious anemia, an autoimmune condition where the immune system attacks intrinsic factor, leading to vitamin B12 deficiency. Identifying these antibodies assists in confirming the cause of B12 deficiency, which is crucial for appropriate treatment.
Indications
- Unexplained symptoms of anemia such as fatigue, weakness, or pallor.
- Neurological symptoms like numbness, tingling, or memory problems.
- Signs of vitamin B12 deficiency noted in blood tests.
- Gastrointestinal symptoms without another clear cause.
- Known autoimmune disorders which can be associated with pernicious anemia.
Preparation
- No special fasting or preparation is generally required.
- Inform the physician about all medications and supplements being taken.
- Blood sample collection may be scheduled at any time since B12 levels are stable throughout the day.
Procedure Description
Blood Sample Collection:
- A healthcare professional cleans the skin with an antiseptic.
- A tourniquet is applied to the upper arm to fill veins with blood.
- A needle is inserted into a vein, usually in the arm, to draw a blood sample.
- The blood is collected in a tube and sent to a laboratory for analysis.
Laboratory Analysis:
- A laboratory specialist tests the blood for intrinsic factor antibodies using specific immunoassay techniques.
Duration
The blood sample collection takes about 5-10 minutes. Laboratory analysis results may take a few days to a week.
Setting
The procedure is usually performed in outpatient settings such as a physician's office, clinic, or laboratory.
Personnel
- Phlebotomist or nurse for blood sample collection.
- Laboratory technician for analysis.
- Physician for interpreting the results.
Risks and Complications
- Minor risks include pain, bruising, or bleeding at the needle insertion site.
- Rarely, infection may occur at the puncture site.
- Most patients experience no significant complications.
Benefits
- Accurate diagnosis of pernicious anemia or other causes of vitamin B12 deficiency.
- Enables appropriate treatment, such as B12 injections or supplements.
- Improved patient management and relief from symptoms with correct diagnosis and intervention.
Recovery
- No recovery time is generally needed.
- Patients can usually resume their normal activities immediately after the blood draw.
- Follow-up appointments might be scheduled to discuss results and treatment plans.
Alternatives
- Schilling test (older and less commonly used).
- Serum vitamin B12 and methylmalonic acid tests to evaluate B12 levels indirectly.
- Endoscopic biopsy if intestinal issues are suspected.
Pros of Alternatives:
- May provide additional information about B12 absorption and related conditions.
Cons of Alternatives:
- More invasive (e.g., Schilling test requires radioactive substances, biopsy involves an invasive procedure).
- May not directly identify the autoimmune cause as effectively as the intrinsic factor antibodies test.
Patient Experience
- Slight pinch or sting during blood draw.
- Temporary soreness or bruising might be experienced at the site of needle insertion.
- Anxiety related to needle insertion can be managed with relaxation techniques or distraction.
- The procedure is straightforward and typically pain-free beyond the initial needle stick.