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Lab Test Dictionary

HIV-1/2 Antigen and Antibodies, Fourth Generation, with Reflexes (91431)


Immunoassay (IA)


4th Generation HIV

Specimen Type

Serum or Plasma

Performing Lab

Quest Diagnostics San Juan Capistrano

Epic ID


Lab Test Days


Standard TAT

1-2 Days

Collection Information

Specimen Required

4-6 mL Blood

Container Type

Gold (SST)

Collection Instructions

Plasma collected in an EDTA (lavender-top) tube is also acceptable.

Processing Information - Lab Use Only

Transport Temperature


Specimen Stability

Room Temp: 72 Hours; Refrigerated: 5 Days; Frozen: 30 Days

Test Volume Required

3 mL Serum

Minimum Test Volume

2 mL Serum

Processing Instructions

Tube should be spun after clotting and remain unopened if collected in a Serum separator tube (SST). However, it is also acceptable to separate serum or plasma into a plastic vial to submit to Quest.

Included Tests

If HIV Antigen and Antibody, 4th Generation Screen is Repeatedly Reactive, HIV 1/2 Antibody Differentiation will be performed. If HIV-1/2 Antibody Differentiation is Indeterminate or Negative, HIV-1 RNA, Qualitative, TMA will be performed.

CPT Codes

87389; 86701, 86702; 87535