T.N. Kiama

Gardnerella vaginalis comprises three distinct genotypes of which only two produce sialidase

OBJECTIVE Sialidase and the presence of Gardnerella vaginalis have been proposed as biomarkers for bacterial vaginosis. Sialidase has been associated with adverse pregnancy outcome. We genotyped G vaginalis isolates, assessed the presence and diversity of sialidase-encoding genes, and determined the production of sialidase. STUDY DESIGN One hundred thirty-four G vaginalis isolates were genotyped by random amplified polymorphic deoxyribonucleic acid (RAPD) and a selection of 29 isolates with amplified ribosomal deoxyribonucleic acid restriction analysis (ARDRA). A G vaginalis sialidase quantitative polymerase chain reaction was developed, and the sialidase production was assessed with the filter spot test. RESULTS Three G vaginalis genotypes could be distinguished by both RAPD and ARDRA. Only 2 genotypes encoded and produced sialidase. CONCLUSION Three genotypes exist among G vaginalis isolates, and there is a clear link between genotype and sialidase production. A possible link between sialidase production and (symptomatic) bacterial vaginosis and biofilm production can be hypothesized.

Characterisation of the vaginal microflora of human immunodeficiency virus (HIV) positive and negative women in a sub-urban population of Kenya.

Lactobacilli predominate normal vaginal microflora and are important in maintenance of vaginal health. The current study set out to identify and compare culture isolates of vaginal microflora of human immunodeficiency virus (HIV) positive (HIV + ) and HIV negative (HIV - ) women at different phases during menstrual cycle from a sub-urban population of Kenya. Seventy four (74) women, 41 HIV + and 33 HIV - , followed up two consecutive menstrual cycles, had high vaginal swabs taken to prepare Gram stains for six visits and anaerobic cultures for four. All 751 isolates identified by t-DNA polymerase chain reaction (PCR) belong to 51 species. Species cultured more frequently in HIV + participants were: Lactobacillus jensenii (p=0.01), Lactobacillus iners (p=0.02), Gardnerella vaginalis (p=0.01) and Peptoniphilus lacrimalis (p=0.01). Species cultured more frequently in HIV- women were Dialister micraerophilus (p=0.02) and Streptococcus agalactiae (p=0.04). Lactobacillus predominating both groups were Lactobacilli crispatus, L. jensenii, L. iners and Lactobacilli vaginalis . Bacterial vaginosis (BV) was equally high in HIV + and HIV - women. Lactobacillus and BV-associated species were cultured more frequently in HIV + women. Minor species differences were found. Predominant Lactobacillus in culture were L. crispatus, L. iners, L. jensenii and L. vaginalis . These women had lower concentrations of lactobacilli in vaginal microflora than observed in previous studies of Caucasian women. Keywords: Vaginal microflora, human immunodeficiency virus (HIV), menstrual cycle, t-DNA polymerase chain reaction (PCR), culture, bacterial vaginosis African Journal of Biotechnology , Vol. 13(9), pp. 1075-1085, 26 February, 2014