From the last wash, supernatant was tested for baseline p24 antigen
levels (0 PID).
Now HIV testing begins with a combination assay that detects HIV-1 and HIV-2 antibodies and the HIV-1 p24 antigen
Viral RNA and p24 antigen
as markers of HIV disease and antiretroviral treatment success.
All negative and discordant samples were screened using HIV RNA and HIV p24 antigen
tests, and Western blot testing was carried out on all samples where HIV RNA was detected.
8) tested patients in the 3 cohorts for p24 antigen
and HIV RNA.
Importantly, no significant differences in HIV RNA plasma (viral load) or p24 antigen
levels were seen between the groups over the year of treatment.
The assay is a chemiluminescent microparticle immunoassay (CMIA) for the simultaneous qualitative detection of HIV p24 antigen
and antibodies to HIV type 1 (HIV-1 group M and group O) and/ or type 2 (HIV-2) in human serum and plasma (EDTA and heparin).
The SANBS results showed that the Novartis Diagnostics Procleix Ultrio assay identified 6,487 HIV-1-positive units of donated blood, 96 of which were not detected by serology and HIV p24 antigen
HIV-1 RNA by polymerase chain reaction (PCR) and p24 antigen
were also negative.
Assays for p24 antigen
are widely available, relatively inexpensive, and highly specific.
Serologic tests for syphilis, Epstein-Barr virus, and HIV antibody were negative except for a p24 antigen
level of 5100 pg/mL.
Additional laboratory steps to reduce HIV infections were implemented by blood banks in 1995 with testing for HIV p24 antigen
, which was proposed to shorten the seronegative window to ~20 days (12); the detection rate of donors who are positive for p24 antigen
but negative for antibody is several cases per year among ~12 million annual blood donations.