Bacterial vaginosis – a disturbed bacterial flora and treatment enigma

Abstract

The syndrome bacterial vaginosis (BV) is characterized by a disturbed vaginal microflora in which the normally occurring lactobacilli yield quantitatively to an overgrowth of mainly anaerobic bacteria. As BV is a possible cause of obstetrics complications and gynaecological disease--as well as a nuisance to the affected women--there is a strong impetus to find a cure. In BV treatment studies, the diagnosis criteria for diagnosis of BV vary considerably and different methods are used for cure evaluation. The design of study protocols varies and there is no consensus respecting a suitable time for follow-up visits. For the purpose of this review, available data were recalculated for 4-week post treatment cure rates. For oral metronidazole the 4-week cure rate was found not to exceed 60-70%. Treatment regimens with topical clindamycin or topical metronidazole have the same cure rates. It can thus be said that no sound scientific basis exists for recommending any particular treatment. There is no evidence of beneficial effects on BV engendered by partner treatment, or by addition of probiotics or buffered gel. Long-term follow-up (longer than 4 weeks) shows a relapse rate of 70%. With a primary cure rate of 60-70%, and a similar relapse rate documented in the reviewed literature, clinicians simply do not have adequate data for determining treatment or designing clinical studies. This is unfortunate since--apart from the obvious patient benefits--clinical studies can often serve as a guide for more basic studies in the quest for underlying disease mechanisms. In the case of BV there is still a need for continued basic studies on the vaginal flora, local immunity to the flora and host-parasite interactions as an aid when designing informative clinical studies.

Randomized clinical trial comparing the efficacy of the vaginal use of metronidazole with a Brazilian pepper tree (Schinus) extract for the treatment of bacterial vaginosis

“…The present study was motivated by the observation that women were embarrassed and inconvenienced by the presence of discharges with a disagreeable odor, with pos- sible repercussions on health arising from such discharges (2,16,17). Furthermore, treatment alternatives are being sought, given that the conventional drugs (metronidazole and clindamycin) involve high relapse rates (18,19).…”

Quantitative PCR Assessments of Bacterial Species in Women with and without Bacterial Vaginosis

“…Moreover, BV flora is of concern because it is associated with an increased risk of adverse sequelae, such as preterm birth (8, 24), postoperative complications in women (40), enhanced risk of acquiring sexually transmitted infections (31), and increased shedding of HIV (11). Treating BV has not proven effective for the prevention of these adverse events possibly due to the fact that standard BV treatment results in high failure and relapse rates (25,29). Furthermore, while suspected pathogens such as G. vaginalis have been implicated, no agent or factor has been identified as the cause of BV, despite experimental (10) and epidemiological (28) evidence that suggests that BV is transmissible (10).…”

Single dose metronidazole, tinidazole and ornidazole in the treatment of bacterial vaginosis - a comparative study

“…8 The lower cure rates in our study could be due to differences in various other hygienic practices.…”

“…There is still a need for continued basic studies on the vaginal flora, local immunity to the flora and hostparasite interactions as an aid when designing informative clinical studies in case of BV. 8 Limitations of this study were, risk factors and adverse effects of drugs were self-reported, and it is possible that there was under-reporting of risk behaviours and adverse effects related to drugs. Furthermore, because there is strong evidence in literature that BV is associated with STIs including HIV further studies are needed to understand the potential role of screening and treatment of BV in STI/HIV prevention programmes.…”