HIV Ag/Ab Combo

Tube Type

Test ID		LAB5169
EPIC Order		HIV Antigen/Antibody Combo
CPT Code(s)		87389, (with 86703, Geenius, if positive)
Group/Individual Test		Individual
Laboratory		Clinical Immunology
Tube Station		30
Specimen	Routine:	5 mL blood/Gold SST tube; See Comments
	Micro:	3 Gold SST bullets
Availability	Routine:	Monday-Friday
	STAT:	Required phone call to lab: 984-974-1815 (Mon-Sat: 8am to 4pm); 984-974-1805 (after hours). Director/supervisor approval may be required.
Turnaround Time		24-72 hours (negative tests)
Reference Range	Normal:	Negative
	Critical Value:	Positive (following confirmatory testing)

Comment		Specimens submitted for HIV antibody testing are assayed using the Abbott Alinity-i HIV Ag/Ab Combo test. The test provides qualitative detection of HIV-1 and HIV-2 antibody as well as HIV-1 p24 antigen simultaneously on an automated platform. It is intended as an aid in the diagnosis of HIV-1/2 infection and acute HIV-1 infection. It is not approved for use in patients less than 2 years of age. Results are reported as either nonreactive for HIV-1/2 antibody and HIV-1 p24 antigen, reactive or indeterminate based on the HIV-1/2 Combo result in conjunction with reflexed follow up testing. Samples with reactive HIV-1/2 Combo results are reflexed to the BioRad HIV-1/2 Geenius assay to differentiate HIV-1 from HIV-2 antibody. Results will state whether the patient is reactive to HIV-1 or HIV-2. Samples that are reactive by the HIV Ag/Ab combo and are negative or indeterminate by Geenius are reflexed to HIV-1 viral load testing to assess the patient for acute HIV-1 infection. See HIV Testing Algorithm .

Reviewed by J. Carr on November 04, 2025

UNC Hospitals
McLendon Clinical Laboratories
101 Manning Drive
Chapel Hill, NC 27514