Antibody to human leukocyte antigens (HLA), solid phase assays (eg, microspheres or beads, ELISA, Flow cytometry); semi-quantitative panel (eg, titer), HLA Class II
CPT4 code
Name of the Procedure:
Antibody to Human Leukocyte Antigens (HLA), Solid Phase Assays (e.g., Microspheres or Beads, ELISA, Flow Cytometry); Semi-quantitative Panel (e.g., Titer), HLA Class II
Summary
This procedure is a laboratory test that detects and measures antibodies against human leukocyte antigens (HLA) Class II in the blood. By utilizing solid phase assays such as microspheres, beads, ELISA, or flow cytometry, it helps to determine the presence and quantity of these antibodies.
Purpose
The test is used primarily to identify and quantify antibodies that can interfere with organ transplants. It helps in assessing the compatibility of organ donors and recipients to minimize the risk of organ rejection.
Indications
- Patients being evaluated for organ transplantation.
- Individuals who have had multiple pregnancies, blood transfusions, or previous transplants.
- Monitoring sensitization levels post-transplant.
Preparation
- No special preparation or fasting is usually required.
- Patients should inform their healthcare provider of any medications they are taking.
- A blood sample will be drawn, and patients may be advised to stay hydrated.
Procedure Description
- A blood sample is collected from the patient, typically from a vein in the arm.
- The collected sample is then processed using one of the solid phase assays:
- Microspheres or Beads: The sample is mixed with microspheres or beads coated with HLA antigens.
- ELISA: The sample is added to a well containing HLA antigens, followed by enzyme-linked secondary antibodies.
- Flow Cytometry: The sample is mixed with fluorescently-labeled HLA antigens.
- Each method allows detection of HLA antibodies by measuring the fluorescence or color change, which is semi-quantitatively analyzed.
- The results provide a titer or level of HLA Class II antibodies present.
Duration
The entire process, from blood draw to obtaining results, usually takes several hours to a couple of days, depending on the laboratory's capabilities.
Setting
The blood draw is typically performed in an outpatient clinic, hospital, or diagnostic laboratory.
Personnel
- Phlebotomist or nurse to collect the blood sample.
- Laboratory technologists to perform the assay.
- A medical specialist, such as a transplant immunologist, to interpret the results.
Risks and Complications
- Mild discomfort or bruising at the blood draw site.
- Rarely, infection at the puncture site.
- No significant risks associated with the lab analysis itself.
Benefits
- Helps in determining compatibility between organ donors and recipients, reducing the risk of rejection.
- Assists in the management and monitoring of patients post-transplantation to identify potential immunological issues.
- Provides critical information for personalized treatment plans.
Recovery
- The patient can resume normal activities immediately after the blood draw.
- Follow-up may be necessary to discuss the testing results with the healthcare provider.
Alternatives
- Crossmatch tests: Directly assess the compatibility between donor and recipient blood samples.
- Panel-reactive antibody (PRA) tests: Measures the level of HLA antibodies in a more general sense.
- Pros and cons vary; for instance, crossmatch provides more immediate compatibility info but is limited to specific donor-recipient pairs.
Patient Experience
- During the blood draw, patients might feel a brief pinch or sting.
- Post-procedure, minor bruising or soreness can occur at the puncture site.
- No pain or discomfort from the laboratory analysis itself.
- Results will be discussed with a healthcare provider to decide the next steps in the transplant process or medical care plan.