12th Conference on Retroviruses and Opportunistic Infections Boston, Massachusetts - February 22-25, 2005

Conf Retrovir Opportunistic Infect 2005 Feb 22-25;12:abstract no. 20

Susan Fiscus¹, C Pilcher¹, W Miller¹, I Hoffman^1,2, M Price¹, D Chilongozi², C Mapanje², R Krysiak^1,2, M Hosseinipour², S Galvin^1,2, S Gama², F Martinson², and M Cohen^1
1Univ of North Carolina at Chapel Hill, USA and ²Univ of North Carolina Project, Lilongwe, Malawi

BACKGROUND: We have previously identified sexually transmitted disease (STD) clinics in Malawi as sites with high proportions of acute HIV infection and thus of high public health concern. We therefore conducted a prospective study to evaluate methods of detecting STD patients who are acutely co-infected with HIV.

METHODS: After obtaining informed consent, all clients with acute STD at Lilongwe Central Hospital in Lilongwe, Malawi, were offered voluntary HIV counseling and testing using 2 rapid tests, Unigold and Determine. Western blot was used as a rapid test tie-breaker, and all rapid test negative (–/–) or discordant (+/–) specimens were tested for p24 antigen (Perkin-Elmer) and also pooled 1:10:50 for Roche Monitor, version 1.5 RNA testing. Initial results were given at a 1-week follow-up visit. Patients with possible acute HIV infection were followed at frequent intervals for 4 months to confirm seroconversion.

RESULTS: A total of 1440 clients (33% female, 67% male) agreed to testing, of whom 555 (38.5%) had established HIV infection and 20 (1.4%) had acute infection; the remainder were uninfected. Median baseline viral load for the 20 acute cases was 599,994 copies/mL, vs 65,899 copies/mL for 84 cases with established infection. Considering all detectable infections, sensitivity of 2 rapid tests was only 96.2%. However, of 22 clients with discordant rapid test results (17 Determine+, 5 Unigold+), 7 (32%) were acutely infected and 2 had established infection. To detect additional HIV infections among rapid test negative/discordant clients, p24 antigen identified 13 of 16 (81%) cases but gave 4 instances of false positive results. RNA tests were 100% sensitive and 99.5% specific.

CONCLUSIONS: These results suggest that a substantial number of people seeking care for acute STD in Malawi have acute HIV co-infection that would be undetected by standard testing. Real-time pooled RNA testing for detection of acute HIV and quality control is feasible at centers of excellence in sub-Saharan Africa; however, parallel rapid testing and p24 antigen testing are technologically simple approaches that together may detect as much as 80% of acute cases. Acutely infected patients are likely to be extremely contagious, and thus deserve special prevention and treatment efforts.

050222
20

Copyright © 2005 - Foundation for Retrovirology and Human Health. Reproduction of this abstract (other than one copy for personal reference) must be cleared through the Foundation for Retrovirology and Human Health. Licensed (AIDSLINE) from National Library of Medicine.