Confirmatory HIV Testing in HIV DNA PCR Positive Children: Retrospective Analysis in Lesotho

1. Post-18 month confirmatory HIV testing in HIV DNA PCR positive children: retrospective descriptive analysis from an operational setting in Lesotho Anthony J. Garcia-Prats, Heather R. Draper, Jill Sanders, Anu Agrawal, Edith Q. Mohapi, Gordon E. Schutze

2. Background • Non-resource-limited settings • 2 virologic tests used to diagnose HIV in children <18 months of age • Resource-limited settings • HIV DNA PCR (PCR) is still unavailable in some places, necessitating presumptive diagnosis • Resource constraints may preclude the use of 2 virologic tests for children <18 months • For these cases, the WHO recommends that these children have HIV-antibody testing after 18 months to confirm HIV infection • Little published data on field implementation of this guideline

3. Case

4. Purpose • Describe results of confirmatory rapid HIV antibody tests, as well as confirmatory HIV DNA PCR and HIV ELISA • Describe factors associated with any falsely negative results

5. Methods 1 • Retrospectively reviewed routine program data • Patient population • Baylor College of Medicine Bristol-Myers Squibb Children’s Clinical Center of Excellence, in Maseru, Lesotho • Pediatric and family HIV clinic • Inclusion criteria • Enrolled in the clinic between Dec-01-2005 through Feb-01-2009 • Positive HIV DNA PCR at <18 months of age • Documented post-18 month rapid test results • Patient characteristics and post-18 month confirmatory test results were reviewed

6. Methods 2 • All HIV testing was done according to Lesotho Ministry of Health and Social Welfare (MOHSW) guidelines • Parallel rapid testing with… • DetermineTM HIV-1/2 (Inverness Medical Innovations, Inc./Abbot Laboratories) • Double-Check GoldTM HIV1&2 (Inverness Medical Innovations, Inc./Orgenics, Ltd.) • HIV DNA PCR using Dried Blood Spot • Processed through Lesotho MOHSW • National Institute for Communicable Diseases laboratory in South Africa using the Amplicor® HIV-1 Test (Roche). • HIV ELISA testing • Done at the national laboratory at Queen Elizabeth II Hospital in Maseru or a private lab in South Africa

7. Results 1

8. Results 2 • Univariate analysis, significant predictors of the combined outcome of discordant or negative confirmatory rapid tests were: • Age at ART initiation <9 months (OR 4.25, p=.002) • Duration on ART ≥9 months (OR 4.96, p<.001) • Other factors were not significant predictors • Gender • PMTCT status • Baseline immunologic status • Acute malnutrition

9. Conclusions 1 • Study limitations • Falsely negative post-18 month confirmatory rapid HIV antibody tests in ART treated children were not a rare phenomenon • A considerable number of post-18 month confirmatory HIV DNA PCRs using DBS were falsely-negative in this operational setting

10. Conclusion 2 • 2/109 children had an initial positive DNA PCR documented in their record, but were ultimately determined to be HIV negative • Importance of not relying on a single PCR to establish the diagnosis • Implications for frontline clinicians and for Early Infant Diagnosis program planning • WHO 2010 recommendations • Additional study is needed to replicate and further elucidate this in more detail

11. Acknowledgements • Baylor International Pediatric AIDS Initiative (BIPAI) • Physicians, staff, and patients of the Baylor College of Medicine Bristol-Myers Squibb Children’s Clinical Center of Excellence – Lesotho • Lesotho Ministry of Health and Social Welfare