Abstract 2588: Increased risk of prevalent high risk human papillomavirus infection in Lactobacillus iners rich microbiota in Nigerian women.
Authors: Dareng Eileen O. , Famooto Ayo O. , Ogbonna Celestine C. , Akarolo-Anthony Sally , Al-Mujtaba Maryam , Odonye George , Olaniyan Olayinka B. , Offiong Richard , Lawal Ishak , Gajer Pawel , Fadrosh Doug , Yang Honqui , Ravel Jacques , Adebamowo Clement 
Published: August 2014

The microbiota plays an important role in prevention of colonization of the vagina by pathogenic organisms such as HIV, Herpes simplex virus and N. gonorrhea. Given the role of persistent high risk HPV (hrHPV) infection of the cervix as a necessary but not sufficient cause of cervical, we hypothesized that in addition to other risk factors, specific community types of vaginal microbiota may be cofactors in the etiology of cervical cancer and pre-cancer (CIN2+).

We enrolled HIV+ and HIV- women who presented to our cervical cancer screening program at the National Hospital, Abuja and the University of Abuja Teaching Hospital, Abuja, Nigeria between April and August 2012 into this study. Using a nurse administered questionnaire, we collected information on demographics and risk factors of cervical cancer. Without cleaning the introitus, we collected mid-vaginal samples and cervical exfoliated cells from all participants.

We characterized the vaginal microbiota from the mid-vaginal sample by using barcoded universal primers 515F and 806R for the amplification of the V3 - V5 hypervariable regions of 16s rRNA gene and sequenced on an Illumina MiSeq Instrument. The processed gene sequences were classified using the RDP Naïve Bayesian Classifier and the vaginal microbiota were clustered into community state types (CST) according to community composition. We used Roche Linear Array HPV Genotyping Test® to characterize the prevalent HPV according to manufacturer's instruction. We analyzed association between community class types of vaginal microbiota and hrHPV infection using Fisher's exact tests.

We enrolled 278 women, 40% (111) of whom were HIV negative, 54% (151) HIV positive and 6% (16) with HIV status unknown. The prevalence of hrHPV types among the HIV- women was 10.6%, and 35.6% among the HIV+ women. hrHPV infection was commoner among HIV positive compared to HIV negative participants (OR 4.67, 95%CI 2.32 - 9.88, p&lt;0.0001). The commonest clusters of vaginal microbiota CSTs that we identified in our sample were - Lactobacillus iners rich CST III and CST IV which lacked significant numbers of Lactobacillus. Amongst the HIV negative enrollees, participants with CST III were more likely to test positive for prevalent hrHPV than participants with CST IV (OR 3.6, 95% CI: 0.88 - 16.96, p = 0.05). Amongst the HIV positive participants, the presence of CST III was commoner among women with prevalent hrHPV but this was not statistically significant (OR 1.14, 95% CI 0.55 - 2.40, p=0.73)

Our results suggest that L.iners rich microbiota may be associated with increased risk of prevalent hrHPV infection in Nigerian women. Further research is needed to confirm this preliminary result and to evaluate the relationship of vaginal microbiota with persistent hrHPV infection.

This work was supported by the UM-Capacity Development for Research in AIDS Associated Malignancy Grant (NIH/NCI 1D43CA153792-01)

Citation Format: Eileen O. Dareng, Ayo O. Famooto, Celestine C. Ogbonna, Sally Akarolo-Anthony, Maryam Al-Mujtaba, George Odonye, Olayinka B. Olaniyan, Richard Offiong, Ishak Lawal, Pawel Gajer, Doug Fadrosh, Honqui Yang, Jacques Ravel, Clement Adebamowo. Increased risk of prevalent high risk human papillomavirus infection in Lactobacillus iners rich microbiota in Nigerian women. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2588. doi:10.1158/1538-7445.AM2013-2588