Comparison between Gram stain and culture for the characterization of vaginal microflora: Definition of a distinct grade that resembles grade I microflora and revised categorization of grade I microflora

Abstract

Background: The microbiological diagnosis of bacterial vaginosis is usually made using Nugent's criteria, a useful but rather laborious scoring system based on counting bacterial cell types on Gram stained slides of vaginal smears. Ison and Hay have simplified the score system to three categories and added a fourth category for microflora with a predominance of the Streptococcus cell type. Because in the Nugent system several cell types are not taken into account for a final score, we carried out a detailed assessment of the composition of the vaginal microflora in relation to standard Gram stain in order the improve the diagnostic value of the Gram stain. To this purpose we compared Gram stain based categorization of vaginal smears with i) species specific PCR for the detection of Gardnerella vaginalis and Atopobium vaginae and with ii) tDNA-PCR for the identification of most cultivable species.

Comparative Functional Genomics of Lactobacillus spp. Reveals Possible Mechanisms for Specialization of Vaginal Lactobacilli to Their Environment

“…This bacteriocin is produced by Pediococcus sp. (26)., individuals of which may also be found in vaginal bacterial communities (7).…”

“…We used multiple databases as follows : (2,7,8). To examine overor underrepresented functional categories among vaginal relative to nonvaginal species, we calculated odds ratios (OR) and tested their significance using Fisher's exact test.…”

“…Furthermore, the relative proportions of community types differed among women of different ethnicities (1). The same four species have been reported to dominate the vaginal communities of healthy women across the world (2)(3)(4)(5)(6)(7)(8)(9). Even though the four Lactobacillus species commonly found and abundant in the human vagina have been isolated from other sites, their occurrence is extremely rare (10)(11)(12)(13)(14).…”

A Review of Current Intravaginal Drug Delivery Approaches Employed for the Prophylaxis of HIV/AIDS and Prevention of Sexually Transmitted Infections

“…Its maintains the natural acidity of the vagina to ensure survival of lactobacilli that are able to produce lactic acid and hydrogen peroxide which inactivate many pathogens that cause STIs (82,90). BufferGel™ acidifies semen, thereby destroying sperm cells, HIV and a wide range of STI pathogens during sexual intercourse and thus creates a physical barrier that inhibits the passage of pathogens into the vaginal and cervical epithelium (90)(91)(92)(93) (Fig. 2).…”

Bacterial Vaginosis Diagnosed by Analysis of First-Void-Urine Specimens

“…At least three of the four criteria must be present to diagnose BV. Different microscopy scores to diagnose BV have been established, some of them based on Gram-stained vaginal smears (4)(5)(6) and others based on wet-smear microscopy (7,8). Among these, the criteria published by Nugent et al (5) are the most widely used and are considered the gold standard for diagnosing BV.…”