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15th Conference on Retroviruses and Opportunistic Infections


Boston, Massachusetts - February 3-6, 2008



PROTECTIVE EFFECT OF VAGINAL LACTOBACILLUS ON GENITAL HIV-1 RNA CONCENTRATIONS: LONGITUDINAL DATA FROM A US COHORT STUDY

Conf Retrovir Opportunistic Infect 2008 Feb 3-6;15: (abstract no. 27LB)

Jane Hitti 1, K Paul1, K Agnew1, R Gausman1, D Lockhart1, S Cohn2, A Luque2, and R Coombs1
1Univ of Washington, Seattle, US; 2Univ of Rochester, NY, US


BACKGROUND: Hydrogen peroxide-producing (H202+) Lactobacillus is a key regulator of the vaginal ecosystem and may decrease HIV-1 replication through direct effects as well as by suppression of pathogenic bacteria. We evaluated the effects of H202+ Lactobacillus on cervicovaginal lavage (CVL) HIV-1 RNA concentrations over time, with the hypothesis that acquisition of H202+ Lactobacillus would result in a decrease in CVL HIV RNA.

METHODS: For this prospective, observational cohort study, 57 HIV-1-infected women from Seattle, Washington (n=38) and Rochester, New York (n=19) contributed 390 visits (median 6, range 1 to 15). Data collection was completed on November 30, 2007. Study visits occurred every 3 to 4 months and included collection of plasma (lower limit of quantitation (LLQ) 30 copies/mL) and CVL (LLQ 1500 copies/mL) samples for HIV RNA quantitation by an independently validated real-time polymerase chain reaction (PCR) assay, and vaginal cultures to identify H202+ Lactobacillus. Longitudinal analyses used linear regression with generalized estimating equations to examine the change in log-transformed CVL HIV RNA between 2 consecutive visits for the same subject, as a function of change in H202+ Lactobacillus colonization, with adjustment for plasma HIV RNA log10 copies/mL and ART.

RESULTS: Of 57 participants, 31 (54%) were on ART and 22 (39%) had undetectable plasma HIV RNA <30 copies/mL at study entry. The 390 study visits yielded 270 visit pairs with complete data for this longitudinal analysis. HIV RNA was detectable in CVL at 47 (17%) of visits, and was highly associated with plasma HIV RNA (P<0.001) but not ART (p<0.78). H202+ Lactobacillus colonization appeared to be dynamic: 121 (47%) of visit pairs had stable colonization between visits, 39 (15%) acquired and 36 (14%) lost H202+ Lactobacillus, and 62 (24%) showed no evidence of H202+ Lactobacillus at either visit. Acquisition of H202+ Lactobacillus resulted in a 0.7 log10 decrease in CVL HIV RNA (p=0.015), while loss of H202+ Lactobacillus resulted in a 0.5 log10 increase in CVL HIV RNA (p=0.029) compared to stable colonization after adjustment for change in plasma HIV RNA and ART status.

CONCLUSIONS: These prospective, longitudinal data demonstrate that acquisition of H202+ Lactobacillus is associated with a significant reduction in vaginal HIV load, while loss of H202+ Lactobacillus results in an increase in vaginal HIV load. These findings may have relevance for secondary prevention strategies.

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2008-02-03
27LB


Copyright © 2008 - 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.