174291 Laboratory Validation of a Proposed CDC/APHL Rapid Testing Algorithm

Tuesday, October 28, 2008: 2:30 PM

Eugene G. Martin, PhD , Department of Pathology & Laboratory Medicine, UMDNJ - Robert Wood Johnson Medical School, Somerset, NJ
Gratian Salaru, MD , Department of Pathology & Laboratory Medicine, UMDNJ - Robert Wood Johnson Medical School, Somerset, NJ
Sindy M. Paul, MD, MPH , New Jersey Department of Health and Senior Services, Trenton, NJ
Rebecca A. Cadoff , Department of Pathology & Laboratory Medicine, UMDNJ - Robert Wood Johnson Medical School, Somerset, NJ
Evan M. Cadoff, MD , Department of Pathology & Laboratory Medicine, UMDNJ - Robert Wood Johnson Medical School, Somerset, NJ
     
Background: Currently, US rapid HIV preliminary positive (PPos) results are confirmed by subsequent EIA and Western Blot (WB) testing and later shared with clients (Problem: 35% don't return).

Objective: Laboratory validation of proposed HIV POCT testing strategies using alternative FDA-approved rapid tests.

Methods: Phase One, using banked sera (Jan 2004-April 2005): WB specimens from all clients testing PPos in NJ counseling sites were re-tested. Phase Two: clients with discordant results (PPos, but negative WB) had blood collected ~ one month later to determine true serostatus. Samples were susequently used to assess assay reproducibility, alternative rapid assay performance and concordance with Western Blot results. Testing logs and test kit distribution data allowed calculation of numbers of clients tested and negative results.

Results: Of 363 serum specimens from PPos clients; 355 (97.8%) were WB positive and confirmed by alternative tests. Of 8 WB negative specimens, 6 were confirmed negative and found negative by alternative strategies. As of May 2007, of 89,961 Oraquick tests, 88,740 (98.6%) were negative, 1221 (1.4%) were PPos. Of the PPos, 1081/1221 (88.5%) were EIA/WB confirmed. Among 140 (11.5%) discordant specimens, 56 were re-tested one month later by alternative rapid HIV assays, by EIA and WB, and by nucleic acid amplification testing (NAAT). All 56 were negative by NAAT and other rapids. None was WB positive. The proposed strategies matched clients' true HIV status.

Conclusions: Proposed CDC/APHL rapid testing strategies are at least as effective as WB in determining the correct HIV serostatus of patients with PPos rapid tests.

Learning Objectives:
Upon completion of this activity, participants should be able to: Describe a recently proposed CDC/APHL rapid HIV testing algorithm Understand the design and conduct of laboratory studies designed to determine whether multiple rapid HIV tests can be used in rapid testing algorithms Define the advantages of a single-visit HIV screening procedures Describe efforts underway in NJ to validate alternative rapid HIV tests as an HIV confirmatory testing methodology Compare the effectiveness of alternative rapid HIV confirmation versus traditional HIV Western blot

Keywords: CDC Guidelines, Access to Care

Presenting author's disclosure statement:

Qualified on the content I am responsible for because: I was a participant in the conduct of all studies being reported.
Any relevant financial relationships? No

I agree to comply with the American Public Health Association Conflict of Interest and Commercial Support Guidelines, and to disclose to the participants any off-label or experimental uses of a commercial product or service discussed in my presentation.

See more of: Learning from the Rest of the World: Development and Implementation of Rapid Test Algorithms for Point-of-Care HIV Testing in the United States
See more of: HIV/AIDS