CPT® Code 81372

Official Description

HLA Class I typing, low resolution (eg, antigen equivalents); complete (ie, HLA-A, -B, and -C)

Common Language Description

The HLA Class I typing, low resolution (CPT® Code 81372), is a laboratory procedure that focuses on identifying specific human leukocyte antigens (HLAs) associated with the major histocompatibility complex (MHC). The MHC plays a crucial role in the immune system by facilitating self-recognition, which allows the body to distinguish its own cells and tissues from foreign invaders, such as pathogens and nonself cells. HLAs are integral to the immune response and are located on the short arm of chromosome 6. Within the HLA system, there are two primary classes: Class I and Class II, with Class I being particularly significant for immune function. The most critical loci within Class I are HLA-A, HLA-B, and HLA-C, each of which can have multiple variants known as alleles. These alleles are identified by a specific nomenclature that includes the locus followed by an asterisk (*) and a series of digits that denote the allele group and its specific characteristics. The HLA typing process is essential for various medical applications, including organ transplantation, where matching donor and recipient HLAs can significantly reduce the risk of transplant rejection. Additionally, HLA typing can provide insights into an individual's susceptibility to certain diseases, including autoimmune disorders and specific cancers. The low resolution typing method identifies antigen equivalents rather than specific alleles, which is sufficient for many clinical purposes. One common technique used for low resolution HLA Class I typing is polymerase chain reaction (PCR) with sequence-specific priming (SSP), which amplifies groups of alleles using a set of primer pairs. This method can be performed using specialized test kits or semi-automated systems. The complete low resolution HLA Class I typing encompasses all three loci: HLA-A, HLA-B, and HLA-C, and is denoted by the code 81372.

1. Indications

The HLA Class I typing, low resolution (CPT® Code 81372) is indicated for various clinical scenarios, including:

Organ Transplantation - To assess compatibility between donors and recipients, reducing the risk of transplant rejection.
Autoimmune Disease Susceptibility - To evaluate an individual's risk for developing certain autoimmune conditions based on HLA types.
Cancer Susceptibility - To identify potential genetic predispositions to specific cancers linked to HLA types.
Transfusion Medicine - To ensure compatibility in blood transfusions, particularly in patients with a history of transfusion reactions.

2. Procedure

The procedure for HLA Class I typing, low resolution, involves several key steps:

Sample Collection - A sample of nucleated cells is obtained, typically from a blood draw or buccal swab, which contains the DNA necessary for testing.
Cell Lysis and Protein Digestion - The collected cells undergo lysis to break down the cell membrane, followed by protein digestion to prepare the DNA for extraction.
DNA Extraction - The DNA is extracted from the lysed cells, isolating it for further analysis.
Polymerase Chain Reaction (PCR) - PCR is employed to amplify specific regions of the DNA that correspond to the HLA Class I loci (HLA-A, HLA-B, and HLA-C). This amplification is crucial for detecting the presence of specific alleles.
Sequence-Specific Priming (SSP) - Using a panel of primer pairs, the PCR process is tailored to amplify groups of alleles, allowing for low resolution typing of the HLA Class I loci.
Analysis and Interpretation - The amplified DNA is analyzed to identify the antigen equivalents present, providing the results for HLA Class I typing.

3. Post-Procedure

After the HLA Class I typing procedure, the results are typically available within a few days, depending on the laboratory's processing capabilities. Patients may not require any specific post-procedure care, as the procedure is minimally invasive. However, it is essential for healthcare providers to discuss the results with patients, particularly in the context of organ transplantation or disease susceptibility. Follow-up consultations may be necessary to interpret the findings and plan any further medical interventions based on the HLA typing results.

Short Descr	HLA I TYPING COMPLETE LR
Medium Descr	HLA CLASS I TYPING LOW RESOLUTION COMPLETE
Long Descr	HLA Class I typing, low resolution (eg, antigen equivalents); complete (ie, HLA-A, -B, and -C)
Status Code	Statutory Exclusion (from MPFS, may be paid under other methodologies)
Global Days	XXX - Global Concept Does Not Apply
PC/TC Indicator (26, TC)	9 - Not Applicable
Multiple Procedures (51)	9 - Concept does not apply.
Bilateral Surgery (50)	9 - Concept does not apply.
Physician Supervisions	09 - Concept does not apply.
Assistant Surgeon (80, 82)	9 - Concept does not apply.
Co-Surgeons (62)	9 - Concept does not apply.
Team Surgery (66)	9 - Concept does not apply.
Diagnostic Imaging Family	99 - Concept Does Not Apply
CLIA Waived (QW)	No
APC Status Indicator	Service Paid under Fee Schedule or Payment System other than OPPS
Type of Service (TOS)	5 - Diagnostic Laboratory
Berenson-Eggers TOS (BETOS)	T1H - Lab tests - other (non-Medicare fee schedule)
MUE	1
CCS Clinical Classification	234 - Pathology

90	Reference (outside) laboratory: when laboratory procedures are performed by a party other than the treating or reporting physician or other qualified health care professional, the procedure may be identified by adding modifier 90 to the usual procedure number.
GZ	Item or service expected to be denied as not reasonable and necessary
26	Professional component: certain procedures are a combination of a physician or other qualified health care professional component and a technical component. when the physician or other qualified health care professional component is reported separately, the service may be identified by adding modifier 26 to the usual procedure number.