Ordering Recommendation

• This 4th generation test screens for HIV-1 p24 antigen and antibodies to HIV-1 (groups M and O) and HIV-2. Repeatedly reactive HIV-1, 2 antigen/antibody screening results will reflex to an HIV-1/HIV-2 antibody differentiation test.
•This test does not complete the 2014 CDC Recommended Algorithm for Laboratory Diagnosis of HIV Infection. Preferred test is Human Immunodeficiency Virus (HIV) Combo Antigen/Antibody (HIV-1/O/2) by CIA, Reflexive Panel (2012674).


Qualitative Chemiluminescent Immunoassay (CLIA)/Qualitative Immunoassay




1-2 days

New York DOH Approval Status

This test is New York DOH approved.

Specimen Required

Patient Preparation



Serum separator tube (SST). Also acceptable: Lavender (EDTA) or pink (K2EDTA).

Specimen Preparation

Separate from cells ASAP or within 2 hours of collection. Transfer 1.5 mL serum into an ARUP standard transport tube. (Min: 0.75 mL) Remove particulate material.

Storage/Transport Temperature


Unacceptable Conditions

Specimens containing particulate material. Severely hemolyzed or heat-inactivated specimens.


After separation from cells: Ambient: 24 hours; Refrigerated: 7 days; Frozen: 8 months (avoid repeated freeze/thaw cycles)

Reference Interval

Test Number
Reference Interval
  HIV 1,2 Combo Antigen/Antibody Negative

Interpretive Data

This test should not be used for blood donor screening, associated reentry protocols, or for screening human cell, tissues, and cellular- and tissue-based products (HCT/P).

Compliance Category



The fourth-generation screen test is for the simultaneous qualitative detection of human immunodeficiency virus type 1 (HIV-1) p24 antigen and antibodies to HIV type 1 (HIV-1 groups M and O) and HIV type 2 (HIV-2). Results of the screen cannot be used to distinguish between the presence of HIV-1 p24 antigen, HIV-1 antibody, or HIV-2 antibody.

The reflexed HIV-1/ HIV-2 antibody differentiation test discriminates between HIV-1 and HIV-2 antibodies. Results for each type are reported.

If the HIV-1,2 combo antigen/antibody screen is repeatedly reactive, then the HIV-1/ HIV-2 antibody differentiation test will be performed. Additional charges apply. A recommendation to order further testing on a separate specimen for HIV-1 nucleic acid will be made for certain results. This multitest algorithm is recommended by the Centers for Disease Control and Prevention (CDC) and was adopted by the Clinical Laboratory Standards Institute (CLSI) for the diagnosis of HIV.

Hotline History


CPT Codes

87389; if reflexed, add 86701; 86702


Component Test Code* Component Chart Name LOINC
2012675 HIV 1,2 Combo Antigen/Antibody 56888-1
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.


  • 4th generation
  • Fourth generation HIV
  • HIV 1,2 Combo Antigen/Antibody
  • HIV Diagnosis
  • HIV Geenius
  • HIV-1 & 2 Antibody Differentiation
  • HIV-1 Antibody by Geenius
  • HIV-1,2 Combo Antigen/Antibody
  • HIV-2 Antibody by Geenius
  • Human Immunodeficiency Virus (HIV) Combo Antigen/Antibody
Human Immunodeficiency Virus (HIV) Combo Antigen/Antibody (HIV-1/O/2) by CIA with Reflex to HIV-1/HIV-2 Antibody Differentiation, Supplemental