HLA Class I typing, high resolution (ie, alleles or allele groups); complete (ie, HLA-A, -B, and -C)
CPT4 code
Name of the Procedure:
HLA Class I Typing, High Resolution (HLA-A, -B, and -C Typing)
Summary
HLA Class I typing is a genetic test to identify specific alleles and allele groups of Human Leukocyte Antigens (HLA) -A, -B, and -C. These antigens are proteins found on the surface of cells that play a crucial role in immune system functioning, especially in organ transplantation and disease susceptibility.
Purpose
HLA Class I typing is primarily used to:
- Determine compatibility for organ and bone marrow transplantation.
- Assess disease susceptibility related to certain HLA types.
- Guide treatment plans for individuals with certain autoimmune conditions.
Indications
- Patients awaiting organ or bone marrow transplantation.
- Individuals with suspected autoimmune disorders.
- People with a family history of HLA-associated diseases.
- Patients participating in certain clinical trials.
Preparation
- No special preparation is usually needed.
- Patients may be advised to inform their physician about any medications they are taking.
Procedure Description
- Sample Collection: A blood sample is collected from the patient, often using a sterile needle. Alternatively, a buccal cheek swab may be used.
- DNA Extraction and Amplification: DNA is extracted from the collected sample and then amplified using Polymerase Chain Reaction (PCR).
- Sequencing: The amplified DNA is sequenced to a high resolution to identify specific HLA alleles.
- Analysis: Specialized software and bioinformatic tools are used to interpret the sequencing data and generate an HLA typing report.
Duration
The procedure typically takes a few hours for sample collection and several days to a couple of weeks for results to be analyzed and reported.
Setting
The sample collection is usually performed in a clinical setting such as a hospital, outpatient clinic, or laboratory.
Personnel
- Phlebotomist or clinician for blood draw.
- Laboratory technicians and molecular biologists for DNA extraction, amplification, sequencing, and analysis.
- Medical geneticists or pathologists to interpret results.
Risks and Complications
- Minimal risks associated with blood draw, such as slight bruising or infection at the puncture site.
- Rarely, complications from the collection process if a buccal swab is used, such as minor discomfort.
Benefits
- Accurate determination of HLA compatibility can significantly reduce the risk of organ transplant rejection.
- Helps in diagnosing and managing certain autoimmune diseases.
- Aids in personalized medical treatment planning.
Recovery
- No specific recovery period is needed for the procedure as it is minimally invasive.
- Patients can return to their normal activities immediately after sample collection.
Alternatives
- Low-resolution HLA typing, which provides less specific information but may be faster and more cost-effective.
- Serological HLA typing, an older method using antibodies to identify HLA molecules, though it is less precise than DNA-based methods.
Patient Experience
- The patient might feel a brief prick during the blood draw or slight discomfort during a buccal swab.
- Post-procedure, they can expect minimal to no discomfort and can resume usual activities right away.
- Any discomfort can be managed with simple over-the-counter pain relief if necessary.