Expedited Confirmatory HIV Testing Information

The 24/7 Illinois Perinatal HIV Hotline offers expedited confirmatory HIV testing at Northwestern Memorial Hospital’s Immunology Laboratory for calls to the Hotline in which an urgent confirmatory HIV test result is needed for clinical decision making. The specimens are processed with a 4th generation HIV-1/2 antigen/antibody laboratory-based test with reflex to the HIV-1/HIV-2 antibody differentiation immunoassay, and the HIV-1 RNA assay (viral load) if needed for confirmation of HIV diagnosis.

  • If you require expedited confirmatory testing, you must first call the Illinois Perinatal HIV Hotline at 1-800-439-4079.

  • All tests must be requested through the Hotline and ordered by a Hotline clinician or else they will not be processed.

Testing Schedule

  • Expedited confirmatory testing is done seven days a week; specimens can be received at Central Specimen Receiving 24 hours a day, 7 days a week.
  • If the specimen is received by 2pm, it will be processed the same day. Otherwise, it will be held until the next routine run the following morning.
  • Turn around time for reporting confirmatory test results is approximately 4 hours after receipt in the lab, unless the specimen is received after 2pm. Then it will be reported approximately 4 hours after the following day’s run.

Specimen Collection and Requirements

  • 3 specimens are required to be sent: 1 gold top vacutainer tube for the HIV-1/2 Ag/Ab w/reflex, and 2 lavender top vacutainer tubes for the HIV-1 RNA assay in case it is needed to complete supplemental testing.
  • Gold Top Tube Specimens Only: Must be collected in dedicated, primary vacutainer tubes. Testing is done on primary tube samples only. The specimen must be received in the original tube. Specimen may get hemolyzed if not separated from cells. If there is access to a centrifuge, please centrifuge the specimen but DO NOT POUR OFF THE SAMPLE.
  • Lavender Top Tube Specimens Only: Specimen must be received in laboratory and spun down within 6 hours of collection. If unable to meet the 6 hour deadline, Lab will accept frozen Aliquots of Plasma. The Plasma Aliquot must be received with the original lavender top tubes and sent on dry ice.
  • All tubes must be labeled with a minimum of 2 unique patient identifiers (Ex. name, date of birth, social security number).
  • Specimens must be accompanied by a completed Northwestern Memorial Hospital Laboratory Requisition.
  • Elements to be completed on requisition include:
    • Patient demographics: Identifiers on the tube must match the requisition
    • Ordering Physician Name: Dr. Lynn Yee
    • Test requested: HIV Antibody (Western Blot confirm) Note: the NMH lab now runs the HIV-1/2 Ag/Ab Combo test and the HIV-1/2 antibody differentiation assay, but the requisition has not yet been updated.
    • “Bill Laboratory Account” box should be checked and account #154461 (Pediatric AIDS Chicago Prevention Initiative) should be used. Complete if information not pre-filled.

Shipment Instructions

  • Send the specimen STAT via FedEx, UPS or courier. Place dry ice pack in the shipping box to keep samples cold/frozen and ship to the following address:

Northwestern Memorial Hospital
Pathology Laboratory-Central Specimen Receiving
251 E. Huron Street
Feinberg Pavilion, Rm. 7-307
Chicago, IL 60611
Attn: Immunology Laboratory

  • Specimen shipment is the responsibility of the hospital sending the specimen. Currently, the Illinois Perinatal HIV Hotline is unable to assist with arranging shipment.

Reporting of Results

  • The Perinatal HIV Hotline ordering physician will be informed of the confirmatory test results and will then report the results to the physician caring for the patient at the external hospital.
  • DO NOT contact the Northwestern Memorial Hospital Outpatient Laboratory directly as it is only authorized to release the results to the ordering Hotline physician and staff.
  • Please call the Hotline directly at 1-800-439-4079 if you have additional questions.

Billing Information

The Perinatal HIV Hotline will be billed for the processing of the expedited tests. It is imperative that you carefully follow the instructions above for completion of the laboratory requisition that must accompany the specimens.