Bacterial vaginosis (BV) is a disease of the vagina caused by excessive growth of bacteria. Common symptoms include increased vaginal discharge that often smells like fish. The discharge is usually white or gray in color. Burning with urination may occur. Itching is uncommon. Occasionally, there may be no symptoms. Having BV approximately doubles the risk of infection by a number of sexually transmitted infections, including HIV/AIDS. It also increases the risk of early delivery among pregnant women.
In bacteriology, gram-positive bacteria are bacteria that give a positive result in the Gram stain test, which is traditionally used to quickly classify bacteria into two broad categories according to their type of cell wall.
Gardnerella vaginalis is a species of Gram-variable-staining facultative anaerobic bacteria. The organisms are small non-spore-forming, nonmotile coccobacilli.
Actinomyces naeslundii is a Gram-positive, rod-shaped bacterium found in the mouth of humans. The species has been implicated in periodontal disease, as well as various tooth cavities. In other cases, A. naeslundii is associated with good oral health. It is one of the first bacteria to occupy the oral cavity and colonize the tooth's surface. It has also been isolated from women with bacterial vaginosis.
Alcaligenes faecalis is a species of Gram-negative, rod-shaped bacteria commonly found in the environment. It was originally named for its first discovery in feces, but was later found to be common in soil, water, and environments in association with humans. While opportunistic infections do occur, the bacterium is generally considered nonpathogenic. When an opportunistic infection does occur, it is usually observed in the form of a urinary tract infection.
Streptococcus bovis is a species of Gram-positive bacteria that in humans is associated with urinary tract infections, endocarditis, sepsis, and colorectal cancer. S. gallolyticus is commonly found in the alimentary tract of cattle, sheep, and other ruminants, and may cause ruminal acidosis or feedlot bloat. It is also associated with spontaneous bacterial peritonitis, a frequent complication occurring in patients affected by cirrhosis. Equivalence with Streptococcus equinus has been contested.
Vaginal discharge is a mixture of liquid, cells, and bacteria that lubricate and protect the vagina. This mixture is constantly produced by the cells of the vagina and cervix, and it exits the body through the vaginal opening. The composition, amount, and quality of discharge varies between individuals and can vary throughout the menstrual cycle and throughout the stages of sexual and reproductive development. Normal vaginal discharge may have a thin, watery consistency or a thick, sticky consistency, and it may be clear or white in color. Normal vaginal discharge may be large in volume but typically does not have a strong odor, nor is it typically associated with itching or pain. While most discharge is considered physiologic or represents normal functioning of the body, some changes in discharge can reflect infection or other pathological processes. Infections that may cause changes in vaginal discharge include vaginal yeast infections, bacterial vaginosis, and sexually transmitted infections. The characteristics of abnormal vaginal discharge vary depending on the cause, but common features include a change in color, a foul odor, and associated symptoms such as itching, burning, pelvic pain, or pain during sexual intercourse.
Atopobium is a genus of Actinomycetota, in the family Coriobacteriaceae. Atopobium species are anaerobic, Gram-positive rod-shaped or elliptical bacteria found as single elements or in pairs or short chains.
The Nugent Score is a Gram stain scoring system for vaginal swabs to diagnose bacterial vaginosis. The Nugent score is calculated by assessing for the presence of large Gram-positive rods, small Gram-variable rods, and curved Gram-variable rods. A score of 7 to 10 is consistent with bacterial vaginosis without culture. The Nugent Score is now rarely used by physicians due to the time it takes to read the slides and requires the use of a trained microscopist. Bacterial vaginosis diagnosis is done by evaluating the pH, the presences of Lactobacillus spp. versus a mixed flora consisting of Gardnerella vaginalis, Bacteroides spp, Mobiluncus spp, and Mycoplasma hominis. The Amsel Criteria for bacterial vaginosis includes pH, evaluating the presence of clue cells, white discharge and an odor of amines after mixing with KOH.
Levilactobacillus brevis is a gram-positive, rod shaped species of lactic acid bacteria which is heterofermentative, creating CO2, lactic acid and acetic acid or ethanol during fermentation. L. brevis is the type species of the genus Levilactobacillus (previously L. brevis group), which comprises 24 species (http://www.lactobacillus.ualberta.ca/, http://www.lactobacillus.uantwerpen.be/). It can be found in many different environments, such as fermented foods, and as normal microbiota. L.brevis is found in food such as sauerkraut and pickles. It is also one of the most common causes of beer spoilage. Ingestion has been shown to improve human immune function, and it has been patented several times. Normal gut microbiota L.brevis is found in human intestines, vagina, and feces.
Vaginal flora, vaginal microbiota or vaginal microbiome are the microorganisms that colonize the vagina. They were discovered by the German gynecologist Albert Döderlein in 1892 and are part of the overall human flora. The amount and type of bacteria present have significant implications for an individual's overall health. The primary colonizing bacteria of a healthy individual are of the genus Lactobacillus, such as L. crispatus, and the lactic acid they produce is thought to protect against infection by pathogenic species.
Cronobacter is a genus of Gram-negative, facultatively anaerobic, oxidase-negative, catalase-positive, rod-shaped bacteria of the family Enterobacteriaceae. Several Cronobacter species are desiccation resistant and persistent in dry products such as powdered infant formula. They are generally motile, reduce nitrate, use citrate, hydrolyze esculin and arginine, and are positive for L-ornithine decarboxylation. Acid is produced from D-glucose, D-sucrose, D-raffinose, D-melibiose, D-cellobiose, D-mannitol, D-mannose, L-rhamnose, L-arabinose, D-trehalose, galacturonate and D-maltose. Cronobacter spp. are also generally positive for acetoin production and negative for the methyl red test, indicating 2,3-butanediol rather than mixed acid fermentation. The type species of the genus Cronobacter is Cronobacter sakazakii comb. nov.
Alistipes is a Gram-negative genus of rod-shaped anaerobic bacteria in the phylum Bacteroidota. When members of this genus colonize the human gastrointestinal (GI) tract, they provide protective effects against colitis, autism, and cirrhosis. However, this genus can also cause dysbiosis by contributing to anxiety, chronic fatigue syndrome, depression, and hypertension. Showcasing priority effects in microbiome assembly, when infant GI tracts have bacteria of the species Staphylococcus but not the species Faecalibacterium, Alistipes species become less capable of colonization.
Fannyhessea vaginae is a species of bacteria in the family Atopobiaceae. It is a facultative anaerobic, Gram-positive rod-shaped or elliptical coccobacillus found as single elements or in pairs or short chains. It is typically isolated from 80% of women with bacterial vaginosis and it is implicated in treatment failures. Invasive infections such as bacteremia have been reported.
Mobiluncus mulieris is a curved, anaerobic bacteria from the vagina of women. Its cells are motile and rod-shaped, having multiple subpolar flagella and multilayered gram-variable cell walls. Its type strain is ATCC 35243. It is often associated with vaginal infections.
Bifidobacterium thermacidophilum is a Gram-positive, rod-shaped species of bacteria. Strains of this species were originally isolated from an anaerobic digester used to treat wastewater from a tofu farm. The species is thermophilic and can grow at a temperature of 49.5 °C.
Peptoniphilus is a genus of bacteria in the phylum Bacillota (Bacteria).
Janibacter is a genus of Gram positive, nonmotile, non-sporeforming bacteria. The genus name is derived from the two-faced Roman god Janus, referring to the fact that the cells of the original strain could be rod-shaped or coccoid.
Ann Patricia Wood is a retired British biochemist and bacteriologist who specialized in the ecology, taxonomy and physiology of sulfur-oxidizing chemolithoautotrophic bacteria and how methylotrophic bacteria play a role in the degradation of odour causing compounds in the human mouth, vagina and skin. The bacterial genus Annwoodia was named to honor her contributions to microbial research in 2017.
