Several fastidious bacteria have been associated with bacterial vaginosis (BV), but their role in lactobacilli recolonization failure is unknown. We studied the effect of 7 BV-associated bacterial species and 2 Lactobacillus species on vaginal colonization with Lactobacillus crispatus CTV-05 (LACTIN-V).
Twenty-four women with BV were given a 5-day course of metronidazole vaginal gel and then randomized 3:1 to receive either LACTIN-V or placebo applied vaginally once daily for 5 initial consecutive days, followed by a weekly application over 2 weeks. Vaginal swabs for L. crispatus CTV-05 culture and 9 bacterium-specific 16S rRNA gene quantitative polymerase chain reaction assays were analyzed on several study visits for the 18 women receiving LACTIN-V.
Vaginal colonization with CTV-05 was achieved in 61% of the participants receiving LACTIN-V at either day 10 or day 28 visit and 44% at day 28. Participants not colonized with CTV-05 had generally higher median concentrations of BV-associated bacteria compared to those who colonized. Between enrollment and day 28, the median concentration of Gardnerella vaginalis minimally reduced from 104.5 to 104.3 16S rRNA gene copies per swab in women who colonized with CTV-05 but increased from 105.7 to 107.3 in those who failed to colonize (P = 0.19). Similarly, the median concentration of Atopobium spp. reduced from 102.7 16S rRNA gene copies per swab to below limit of detection in women who colonized with CTV-05, but increased from 102.7 to 106.6 in those who failed to colonize (P = 0.04). The presence of endogenous L. crispatus at enrollment was found to be significantly associated with a reduced odds of colonization with CTV-05 on day 28 (P = 0.003), and vaginal intercourse during the study significantly impaired successful CTV-05 colonization (P = 0.018).
Vaginal concentration of certain BV-associated bacteria, vaginal intercourse during treatment, and the presence of endogenous L. crispatus at enrollment predict colonization with probiotic lactobacilli.
Vaginal concentrations of 7 bacterial vaginosis-associated bacterial species and 2 Lactobacillus species as well as sexual intercourse can affect colonization by Lactobacillus crispatus CTV-05, a probiotic.
From the *Centre for Microbiology Research, Kenya Medical Research Institute (KEMRI), Nairobi, Kenya; †Institute of Tropical Medicine and Infectious Diseases, Jomo Kenyatta University of Agriculture and Technology, Nairobi, Kenya; ‡Department of Obstetrics, Gynecology and Reproductive Sciences, University of California, San Francisco, CA; §Department of Global Health, University of Washington, Seattle, WA; ¶Department of Biostatistics, University of California, San Francisco, CA; ∥Fred Hutchinson Cancer Research Center, Seattle, WA; and **Department of Medicine, University of Washington, Seattle, WA
We wish to express our gratitude to all participants, all referral clinics of Planned Parenthood Golden Gate as well as the San Francisco City Clinic, the study clinicians performing the clinical visits, the staff of the CTSI Clinical Research Center at the San Francisco General Hospital, the data management team at DF/Net Research in Seattle, as well as the study sponsor Osel Inc. of Santa Clara, CA. Daisy Ko at the Fred Hutchinson Cancer Research Center provided technical support for all the qPCR assays performed in this study.
Supported by a grant from Osel Inc. This study was also supported by grant UL1 RR024131-01 from the National Center for Research Resources (NCRR), a component of the National Institutes of Health (NIH), and NIH Roadmap for Medical Research. Its contents are solely the responsibility of the authors and do not necessarily represent the official view of NCRR or NIH. BMN is a fellow of the Infectious Disease Research Training Program (IDRTP) an affiliate program of the University of California, San Francisco, USA and the Kenya Medical Research Institute, Nairobi, Kenya (NIH Fogarty International).
Correspondence: Benjamin M. Ngugi, Centre for Microbiology Research, Kenya Medical Research Institute, P.O. Box 19464-00202 Nairobi, Kenya. E-mail: email@example.com.
Received for publication January 28, 2011, and accepted May 24, 2011.