Hindawi Publishing Corporation Infectious Diseases in Obstetrics and Gynecology Volume 2009, Article ID 236919, 6 pages doi:10.1155/2009/236919 Research Article Detection of Fastidious Vaginal Bacteria in Women with HIV Infection and Bacterial Vaginosis Caroline Mitchell,1 Carla Moreira,2 David Fredricks,1, 3 Kathleen Paul,1 Angela M. Caliendo,4, 5 Jaclynn Kurpewski,2 Jessica Ingersoll,4, 5 and Susan Cu-Uvin2 1 Department of Obstetrics & Gynecology, University of Washington, P.O. Box 356460, Seattle, WA 98195, USA 2 Department of Obstetrics & Gynecology, Brown University, Providence, RI 02912, USA 3 Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA 4 Department of Pathology and Laboratory Medicine, Emory University, Atlanta, GA 30322, USA 5 Emory Center for AIDS Research, Emory University, Atlanta, GA 30322, USA Correspondence should be addressed to Caroline Mitchell, camitch@u.washington.edu Received 6 January 2009; Accepted 6 October 2009 Recommended by Harold Wiesenfeld Background. Fastidious bacteria have been associated with bacterial vaginosis (BV) using PCR methods. We assessed the prevalence of these bacteria in HIV-1 infected women and their relationship with vaginal pH and shedding of HIV-1 RNA. Methods. 64 cervicovaginal lavage (CVL) samples were collected from 51 women. Vaginal microbiota were characterized using 8 bacterium- speciﬁc quantitative PCR assays. Results. Women with the fastidious bacteria Bacterial Vaginosis Associated Bacterium (BVAB) 1, 2, and 3 showed a trend to increased HIV-1 shedding (OR 2.59–3.07, P = .14–.17). Absence of Lactobacillus crispatus (P < .005) and presence of BVAB2 (P < .001) were associated with elevated vaginal pH. BVAB1, 2, and 3 were highly speciﬁc indicators of BV in HIV-infected women, with speciﬁcities of 89%–93%. Conclusions. Fastidious bacteria (BVAB 1, 2, and 3) remain speciﬁc indicators of BV in HIV-infected women, and BVAB2 may contribute to the elevated vaginal pH that is a hallmark of this syndrome. Copyright © 2009 Caroline Mitchell et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. 1. Background Bacterial vaginosis (BV) is a vaginal infection characterized by loss of the normal protective lactobacilli and overgrowth of diverse anaerobes [1, 2]. This infection is one of the leading causes of vaginal discharge [3] and is more prevalent in HIV-1-infected women compared to uninfected women [4]. The microbiology of BV is heterogeneous, and culture- based description of the vaginal microbiota identiﬁes far fewer organisms than broad range molecular methods [5, 6]. Several fastidious bacteria in the Clostridiales order have recently been associated with BV using PCR methods [7] and appear to be highly speciﬁc markers of BV [8]. BV has been associated with increased genital HIV shedding [9], having high concentrations of Gardnerella vaginalis and Mycoplasma hominis [10], but the mechanism accounting for this association is poorly understood. In HIV-1-infected women, polymerase chain reaction (PCR) methods have shown that high concentrations of Gardnerella vaginalis and Mycoplasma hominis are sensitive indicators for the diagnosis of BV [11]. It is possible that some of the proinﬂammatory vaginal cytokines seen in subjects with BV [12, 13] increase production of the virus or stimulate epithelial turnover and microtears in the vaginal wall that facilitate viral shedding. A second hypothesis is that loss of hydrogen peroxide-producing lactobacilli and subsequent increase in vaginal pH results in loss of viral inhibition [14]. Lactobacilli and G. vaginalis have been associated with changes in vaginal pH [15], but little is known about the eﬀect of the fastidious organisms present in BV. We hypothesize that fermentation products from key vaginal anaerobes may alter the vaginal pH and facilitate production and shedding of HIV. We sought to determine the prevalence of several fastidious vaginal bacteria in HIV- infected women and to assess the impact of these bacterial species on (1) vaginal pH and (2) shedding of HIV-1 RNA in women with and without BV.