Human Immunodeficiency Virus 1 (HIV-1), Quantitative, Real-time PCR (Nongraphical) With Reflex to PhenoSense®

Casandra

Casandra Test Code LC48903Version 1 (DRAFT)

Performing Lab

Lab LabcorpLab Test ID 550470CPT Code 87536

Human Immunodeficiency Virus 1 (HIV-1), Quantitative, Real-time PCR (Nongraphical) With Reflex to PhenoSense®

Clinical Use

Use

This test is used to detect and quantitate human immunodeficiency virus type 1 (HIV-1) in plasma. It incorporates a reflex mechanism to perform phenotype testing (PhenoSense®) if the viral load exceeds 500 copies/mL, which helps in determining the virus's resistance to antiretroviral drugs. This quantitation is essential for managing and tailoring antiretroviral therapy for patients with HIV-1 infection.

Special Instructions

Ensure that specimens are collected in the specified tubes and processed within the recommended time frame to avoid delays. Plasma should be frozen and stored in screw-cap tubes, as 'pop-top' or 'snap-cap' tubes are unsuitable. Separate frozen samples are required for the PhenoSense® component.

Limitations

The assay has a dynamic range of 20 to 10,000,000 copies/mL, limiting its sensitivity for detecting viral loads below 20 copies/mL. Variability in sample processing or storage can affect the results, particularly if specimens are not appropriately frozen or are transferred in unsuitable containers. Use of green-top tubes or receiving insufficient samples may lead to rejection of specimens.

Test Details

Methodology

PCR-based (RT-PCR)

Biomarkers

HIV-1

Microorganism

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

log10 HIV-1 RNA • Concentration / Level • Quantitative (Continuous) (e.g., copies/mL, % expression)

PhenoSense® • Other • Categorical (e.g., Positive / Negative / Indeterminate)

LOINC Codes

Order Codes

20447-9

Result Codes

20447-9
29541-0
45182-3
49665-3
48767-8

Result Turnaround Time

17-25 days

Specimen

Plasma

Volume

6 mL

Minimum Volume

4 mL

Container

Screw-cap polypropylene frozen transport tubes

Collection Instructions

Collect in three lavender-top (EDTA) tubes or three PPT™ tubes. Centrifuge within six hours and transfer plasma to screw-cap tubes before freezing. Avoid green-top (heparin) tubes and ensure samples are frozen for shipping.

Storage Instructions

Separate frozen sample is required for PhenoSense® testing. Plasma stable at room temperature (1 day) or refrigerated (5 days); freeze for long-term storage.