HIV-1 RNA, Quantitative, Real‑Time PCR with Reflex to Genotype (RTI, PI, Integrase)

Casandra

Casandra Test Code QD46496Version 1 (DRAFT)

Performing Lab

Lab Quest DiagnosticsLab Test ID 91691CPT Codes 87536, 87900, 87901, 87906

HIV-1 RNA, Quantitative, Real‑Time PCR with Reflex to Genotype (RTI, PI, Integrase)

Also known as: Human Immunodeficiency Virus

Clinical Use

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Use

Used to monitor HIV‑1 viral load in patients undergoing antiretroviral therapy, this test measures quantitative levels of HIV‑1 RNA. If viral load exceeds thresholds indicating virologic failure, the assay reflexively triggers genotypic resistance testing in reverse transcriptase inhibitor, protease inhibitor, and integrase regions to aid in treatment management and detection of drug resistance.

Special Instructions

Reflex testing to genotype (RTI, PI, Integrase) is automatically performed when HIV‑1 RNA level exceeds the specified threshold for virologic failure. Additional charges apply for genotype testing. Ensure proper plasma separation and transport per specimen requirements.

Limitations

Genotyping requires a minimum viral load (recommended 500–1,000 copies/mL); undetectable or low-level viral loads may not produce reliable genotype results. RNA degradation due to improper collection, storage, or transport can lead to failure to amplify, reflected as “Not Detected.”

Test Details

Methodology

PCR‑based (RT‑PCR)

Biomarkers

HIV‑1 RNA

Other

HIV‑1 RNA • Concentration / Level • Quantitative (Continuous) (e.g., copies/mL, % expression)

LOINC Codes

Order Codes

20447-9

Result Turnaround Time

2-4 days

Specimen

Plasma

Volume

7 mL

Minimum Volume

3.7 mL

Container

EDTA (lavender‑top) tube

Collection Instructions

Do not freeze whole blood in primary tube. Fresh whole blood may be stored at 2‑25 °C for up to 24 hours prior to centrifugation. Separate plasma within 24 hours.