Clinical Context
A 38-year-old patient with known HIV-1 infection presents to an infectious disease clinic with rising plasma viral load and suboptimal virologic response after a change in antiretroviral regimen. The clinician orders genotypic and phenotypic resistance testing from a laboratory that performs nucleic acid analysis and culture-based drug susceptibility testing. A specimen (plasma or tissue-derived viral isolate) is collected and sent to a reference virology lab. In the laboratory workflow, a lab analyst extracts nucleic acids from the sample, performs culture and phenotypic assays to assess HIV-1 susceptibility to antiretroviral agents, and reports resistance results for up to the first 10 drugs tested. Results are returned to the ordering clinician to guide selection of an effective antiretroviral regimen.
Coding Specifications
| Modifier | Description | When to Use |
|---|
26 | Professional Component | Use when billing for the interpretive/professional portion of the test if separated from the technical component. |
59 | Distinct Procedural Service | Use when this service is distinct from other procedures performed on the same day and not normally reported together.
62 | Two Surgeons | Use when two qualified laboratory directors/physicians are required and share responsibility (rare for this test).
90 | Reference (Outside) Laboratory | Use when the service was performed by a laboratory other than the billing laboratory.
TC | Technical Component | Use when billing only for the technical component (lab performance) of the test.
26 and TC note: In many lab settings, either TC or 26 is appended, not both.
QK | CLIA Waiver or Provider-Performed Microscopy (PPM) Exemption | Use when applicable for specialized lab arrangements or personnel (rare for HIV resistance testing).
QX | Modifier for Certified Nurse Anesthetist (not applicable clinically but included in list) | Generally not used for this lab test; included when billing requires credential-based modifiers.
59 and 90 are commonly paired when an outside reference lab performs a distinct test.
| Taxonomy Code | Specialty | Notes |
|---|
207RG0100X | Infectious Disease Specialist | Physicians ordering and interpreting HIV resistance testing. |
207LH0000X | Laboratory Director | Pathologists or laboratory medicine physicians overseeing testing and reporting.
2080P0208X | Clinical Pathology | Laboratory specialty performing virology assays and culture-based drug susceptibility testing.
334MP0800X | Microbiologist | Technical staff and specialists who run culture and susceptibility analyses.
Related Diagnoses
| ICD-10 Code | Description | Clinical Relevance |
|---|
B20 | Human immunodeficiency virus [HIV] disease | Primary diagnosis indicating HIV infection; rationale for performing resistance testing when viral failure or treatment change is suspected. |
R77.1 | Abnormality of HIV antibody [serologic test] | May appear in the record when serologic testing has indicated HIV infection prior to resistance testing.
Z21 | Asymptomatic human immunodeficiency virus [HIV] infection status | Relevant for patients with HIV infection in chronic care who may require resistance testing if treatment failure occurs despite asymptomatic status.
B97.89 | Other viral agents as the cause of diseases classified elsewhere | Occasionally used in complex virology reporting contexts alongside HIV testing.
T86.10 | Infection and inflammatory reaction due to cardiac prosthetic device, unspecified — Data not available in the input. | Data not available in the input.
Related CPT Codes
| CPT Code | Description | Relationship to This Procedure |
|---|
87903 | The lab analyst performs the technical lab test to analyze the nucleic acids from a sample of tissue from an HIV 1 positive patient to determine drug resistance through culture analysis for up to the first 10 drugs tested. | Primary technical service for culture-based HIV-1 drug resistance testing; billed for the lab performance of the assay. |
87904 | Laboratory analysis for HIV-1 drug resistance by phenotypic methods for additional drugs beyond the first 10 tested (hypothetical companion code). | May be used when more than 10 drugs are evaluated or for additional phenotypic panels following initial testing.
87661 | Infectious agent detection by nucleic acid (e.g., HIV-1 RNA), amplified probe technique, quantitative. | Often performed prior to or concurrently with resistance testing to quantify viral load and confirm specimen suitability for phenotypic assays.
87663 | HIV-1 quantification, viral load testing via nucleic acid; used in monitoring therapy response. | Viral load measurement informs interpretation of resistance testing and clinical decision-making.
87389 | Antibody/antigen detection assays for HIV may be part of the diagnostic workflow before resistance testing. | Used earlier in the diagnostic pathway; less directly related but may appear in the patient's testing history.