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METHODS  Based on initial OraQuick Post-Marketing Survey, the CDC made the recommendation that a discordant result should be followed-up by antibody testing.

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Presentation on theme: "METHODS  Based on initial OraQuick Post-Marketing Survey, the CDC made the recommendation that a discordant result should be followed-up by antibody testing."— Presentation transcript:

1 METHODS  Based on initial OraQuick Post-Marketing Survey, the CDC made the recommendation that a discordant result should be followed-up by antibody testing a month after the initial discordant result was obtained.  Antibody-based testing at one month consists of an HIV 1 / 2 EIA or Western blot. Even though a rapid test is antibody-based, a repeat rapid test is not part of the currently accepted follow-up algorithm.  The use of an OraSure device, that collects oral fluid, is transported to a central laboratory for Western blot testing is accepted as a follow-up method.  In the NJHIV program, the follow-up protocols included EIA HIV 1 / 2 testing followed by Western blot if positive, but also HIV molecular testing by PCR, most commonly RNA-based quantitative HIV RT-PCR.  Negative results at the one month follow-up was accepted as an indication that the original positive result was a true false-positive result.  The major inconveniences of this protocol were the long time interval to resolution of the case and the fact that a considerable number of patients did not return for the scheduled one-month follow-up.  In an effort to resolve these discordant cases, the Notification Assistance Program, from the New Jersey Department of Health and Senior Services was involved. NAP personnel were notified about patients who did not return for follow-up (strict confidentiality maintained). NAP re-enforces the importance of the follow-up testing and often obtains oral fluid for an OraSure EIA and fluid Western blot determination.  Despite all efforts, a significant number of clients were unreachable (either wrong/incorrect contact information or outright refusal to cooperate even when NAP reached a particular client).  Two new protocols were initiated at several pilot sites to address these shortcomings.  One protocol called for collection of two pearl-white plasma separator tubes (PPT) at the time of collection for the initial confirmatory Western blot test.  The second protocol required collection of the same pearl-white plasma separator tubes at the time the client returns for the confirmatory result, usually 5-7 days from the original test date. ABSTRACT ISSUE: Rapid HIV testing methodology has greatly improved the ‘time to result’ for the average client being screened, and has reduced the ‘lost to follow-up’ rate from 35% to less than 1%. However, discordant results (positive rapid tests which do not confirm by Western Blot) create considerable anxiety and ordinarily involve long delays until final resolution. Distinguishing between exiting the HIV antibody window and a real false positive is an important distinction in clients engaging in high risk behavior. SETTING: In 2004, based on the original OraQuick Post-Marketing Survey, the CDC recommended that follow-up antibody testing be performed one month after initial discordant result was obtained. In New Jersey, follow-up testing at one month included HIV 1/2 EIA with Western Blot if positive, and nucleic acid testing for both DNA and RNA HIV viral load. Patients who tested negative at the one month follow-up were deemed real false positives. The major disadvantage of this approach is the failure of patients to return one month after the initial test. PROJECT: In order to improve on follow-up, the NJ Notification Assistance Program (NAP) was used to augment the outreach efforts of the testing sites. NAP had been used to reach confirmed positives who did not return for referral to care and treatment. NAP now reaches out to clients with discordant results who did not return for follow-up testing. NAP re-enforces the importance of the follow-up and often obtains oral fluid for OraSure EIA and fluid Western Blot determination. A new protocol for testing preliminary positive clients was recently introduced. In addition to blood for Western Blot, we are now also collecting additional specimens for follow-up testing. If the Western blot result is discordant, the additional plasma is immediately sent for nucleic acid testing. All tests are complete by the time the client returns for the confirmatory test results. This eliminates the one-month waiting period, and provides much-desired final disposition to the patients. A true positive client exiting the window period is detected up to three weeks earlier, and a false positive is resolved without the emotional duress implied by a four week wait. Resources required for outreach to clients who fail to return for testing are also greatly reduced. Because specimens are only sent if the results are discordant the cost impact on the program is marginal and off-set by significant labor saving costs. RESULTS: Despite efforts of counselors to have clients return for follow-up, only about half of clients with discordant results returned for follow-up testing. In 2006, NAP outreach workers were responsible for 19% of the successful follow-up testing. But the number of clients who do not return for testing continues to increase. The first preliminary positive client under our newest protocol has had all results available, including nucleic acid testing, within ten days. LESSONS LEARNED: Outreach efforts for resolving discordant results continue to be frustrated by clients not returning for follow-up. Revised protocols can allow for more effective and timely resolution of discordant results. INTRODUCTION  Rapid HIV testing improved the time to result (10 to 20 minutes depending on method) and overall decreased the numbers of people that had an HIV test but never received results from 35% to about 1%.  Positive rapid HIV results are “preliminary” in currently established testing algorithms and require additional confirmatory testing, usually performed on serum collected by venipuncture and transported to a specialized laboratory.  Occasionally, individuals have a preliminary positive rapid test and a negative or indeterminate Western blot result. These criteria define a discordant test result.  Discordant results create considerable anxiety and ordinarily involve long delays until final resolution.  Distinguishing between exiting the HIV antibody window and a real false positive is an important distinction in clients engaging in high risk behavior. RESULTS  Since January 2006 there were a total of 162 discordant cases recorded by NJHIV: in 2006 there were 77 cases and in 2007 (including October 2007) there were 85 cases  In 2006, 34% (26 clients) of the discordants were lost to follow-up. These cases failed to return for the one month follow-up session, and include several that did not return for the confirmatory notification either. According to the strategy in place at that time, NAP was notified and achieved success in 19% of the follow-up cases but was not able to reach several clients or were refused cooperation.  In 2007, 26% (22 clients) of the discordants were lost to follow-up.  The decreased numbers, despite increased testing volume are likely attributable to a more efficient and aggressive follow-up strategy (Graph 1).  In 2006, using the “old” strategy the median time for resolution of a discordant case was of 36 days with an average of 50.9 days.  In 2007, overall, considering that new strategies were introduced only in July of 2007, the median time for resolution was of 28 days with an average of 35.3 days.  At the pilot sites involved with the new strategies results were excellent:  with strategy #1, the sites were able to reach a final resolution is as little as 6 days from the original rapid result (range 6 to 12 days)  with strategy #2, the final resolution was reached in as little as 9 days (range 9 to 21 days)  overall, including non-pilot sites, the average time for final resolution since the implementation of the new strategies decreased to 17.9 days The winner in the time race is clearly strategy #1, with collection of plasma at the time of confirmatory specimen draw. However, in trying to expand the strategy to other sites, several problems were encountered:  Hardware problems:  centrifuges, capable of accepting the plasma separator tubes (apparently of a different design than the regular serum/red top tubes used by the sites)  the requirement to centrifuge the sample and separate the plasma within two hours of collection  freezers, required to freeze the separated plasma until picked-up by NJHIV staff for shipment to reference laboratory  Logistical problems:  phlebotomist availability, on-site  qualified personnel for centrifuge and plasma separation  courier or staff member availability for transporting of the specimen  Unfortunately, the best strategy proved to also be the least feasible when the majority of the testing sites were considered. Not many sites besides the pilot ones had centrifuges available. While all sites had refrigerators (combo models with freezer compartment on top) in our experience these freezer units were unfortunately not performed enough to assure freezing of the plasma samples within the time recommended. CONCLUSIONS  Outreach efforts for resolving discordant results continue to be frustrated by clients not returning for follow-up.  Revised protocols can allow for more effective and timely resolution of discordant results.  The “best” protocol, that generated the shortest turnaround time for discordant follow-up was unfortunately impractical.  While further evaluation is required, the currently described protocol appears balanced in regards to costs, hardware requirements and efficacy. Even so, cases where clients failed to return for the confirmatory result notification continue to plague this strategy HIV Discordant Follow-up: An Evolving Process Gratian Salaru 1, Eugene G Martin 1, Sindy M Paul 2, Linda Berezny 2, Maureen Wolski 2, Ismael Vega 2, Evan Cadoff 1 1 University of Medicine and Dentistry of New Jersey, Robert Wood Johnson Medical School 2 New Jersey Department of Health and Senior Services, Division of HIV/AIDS Services Current strategy Positive rapid result Confirmation WB Client notification Schedule 1 month follow-up 1 month follow-up testing Final resolution to client through EIA/WB and RNA HIV viral load test New strategy #1 Positive rapid result Confirmation WB Client notification of discordant result AND final resolution to client through RNA HIV viral load test Draw two PPT Final resolution to client through RNA HIV viral load test New strategy #2 Positive rapid result Confirmation WB Client notification of discordant result Draw two PPT at time of notification Graphic. 2 Please note that for the 2007#1 and 2007#2 columns, data reflects only discordant cases included in the respective strategy. These strategies were implemented starting in June of 2007 and include discordant cases to October of 2007 Graph 1. Discordant cases recorded by NJHIV and no- follow-up situations 2006-2007


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