How To Use CPT Code 81373

CPT 81373 describes the low resolution typing of HLA Class I genes using molecular techniques. This article will cover the description, procedure, qualifying circumstances, appropriate usage, documentation requirements, billing guidelines, historical information, similar codes and billing examples.

1. What is CPT Code 81373?

CPT 81373 is used to identify specific alleles for one HLA Class I locus, such as HLA-A, -B, or -C. This code represents low or intermediate resolution typing, which means it identifies the alleles without high specificity, such as to the level of the two-digit HLA name or a string of alleles. The test is performed using molecular techniques to assess the compatibility of donors and recipients for solid organ or hematopoietic stem cell transplants. It can also be used to identify specific HLA Class I alleles associated with certain disease states.

2. Official Description

The official description of CPT code 81373 is: ‘HLA Class I typing, low resolution (eg, antigen equivalents); one locus (eg, HLA-A, -B, or -C), each.’

3. Procedure

1. The lab analyst performs the technical steps of the test, including extracting nucleic acids and identifying target HLA gene sequences using methods such as amplification and hybridization with nucleic acid probes or direct sequencing-based typing.

4. Qualifying circumstances

CPT 81373 is used when low or intermediate resolution typing is performed for one HLA Class I locus, either HLA-A, -B, or -C. This test is ordered to assess donor/recipient compatibility for transplants or to identify specific HLA Class I alleles associated with certain disease states.

5. When to use CPT code 81373

CPT code 81373 should be used when low or intermediate resolution typing is performed for one HLA Class I locus. It should not be used for high-resolution typing or when testing involves more than two antigen equivalents at a single locus.

6. Documentation requirements

To support a claim for CPT 81373, documentation should include:

• Reason for the test, such as donor/recipient compatibility assessment or identification of specific disease-associated alleles
• Specific HLA Class I locus tested (HLA-A, -B, or -C)
• Date of the test
• Results of the test, including the identified alleles
• Signature of the lab analyst performing the test

7. Billing guidelines

When billing for CPT 81373, ensure that the test performed is low or intermediate resolution typing for one HLA Class I locus. Do not report this code for high-resolution typing or when testing involves more than two antigen equivalents at a single locus. There are no specific guidelines regarding reporting this code with other codes.

8. Historical information

CPT 81373 was added to the Current Procedural Terminology system on January 1, 2012. There have been no updates to the code since its addition.

9. Examples

1. A lab analyst performs low-resolution HLA typing for HLA-A for a patient awaiting a kidney transplant.
2. Low-resolution HLA typing for HLA-B is performed to identify specific alleles associated with a patient’s autoimmune disease.
3. A lab analyst conducts low-resolution HLA typing for HLA-C to assess donor/recipient compatibility for a bone marrow transplant.
4. Low-resolution HLA typing for HLA-A is performed to determine the likelihood of a patient developing an adverse reaction to a specific medication.
5. A lab analyst performs low-resolution HLA typing for HLA-B to identify specific alleles associated with a patient’s increased risk of developing certain cancers.
6. Low-resolution HLA typing for HLA-C is conducted to assess the compatibility of a potential organ donor and recipient for a heart transplant.
7. A lab analyst performs low-resolution HLA typing for HLA-A to identify specific alleles associated with a patient’s susceptibility to infectious diseases.
8. Low-resolution HLA typing for HLA-B is performed to determine the likelihood of a patient developing an allergic reaction to a specific substance.
9. A lab analyst conducts low-resolution HLA typing for HLA-C to assess the compatibility of a potential bone marrow donor and recipient.
10. Low-resolution HLA typing for HLA-A is performed to identify specific alleles associated with a patient’s increased risk of developing autoimmune disorders.