Test Code HIV4G HIV 4th Gen Screen
Additional Codes
EPIC: LAB5383
Performing Laboratory
UnityPoint The Finley Hospital
Test Method
Chemiluminescent immunoassay (Sandwich principle); Roche cobas Pro
Performance
Testing is performed Monday through Sunday.
Routine: Typically completed within the same day after the specimen arrives at the laboratory.
STAT: Typically completed within 1 hour after the specimen arrives at the laboratory.
Specimen Requirement
- Serum, EDTA plasma, lithium heparin plasma, and gel tubes are acceptable.
- It is recommended that the serum be separated from contact with cells within 2 hours from time of collection.
- HIV specimens are stable for 7 days at 20-25°C, 4 weeks at 2-8°C, and 3 months at -20°C.
Useful For
ImmunoDeficiency Syndrome (AIDS), belongs to the family of retroviruses. HIV can be transmitted through sexual contact, contaminated blood and blood products or from an HIV-infected mother to her child before, during and after birth. Two types of HIV, called HIV‑1 and HIV‑2, have been identified to date. HIV‑1 can be divided into 4 distantly related groups: group M (for main), group N (for non‑M, non‑O), group O (for outlier) and group P (Plantier).
HIV p24 antigen in blood specimens of recently infected patients can be detected as early as 2‑3 weeks after infection. Anti‑HIV antibodies are detectable in serum from around 4 weeks post infection. The combined detection of HIV p24 antigen and anti‑HIV antibodies in 4th generation HIV screening assays leads to improved sensitivity and therefore a shorter diagnostic window compared to traditional anti‑HIV assays.
Reference Values
Nonreactive
Reactive results are considered preliminary positive and are sent to Pathology Laboratory for confirmation testing.