Vulvovaginitis: Candidiasis and Bacterial Vaginosis
Vulvovaginal infections are a common reason for consultation representing 20% of gynaecological consultations. 75% of women experience one episode of symptomatic vulvovaginitis throughout their life and 40-50%, at least, have a second episode.
Vulvovaginitis is inflammation of the vaginal mucosa and of the vulvar skin, although both areas are not always affected simultaneously.
Candidal vulvovaginitis is caused by different species of fungi, fundamentally Candida, with Candida albicans being responsible for 90% of episodes of vulvovaginal candidiasis. These candidas usually live in a woman's vagina in a small quantity and without producing symptoms, but when an alteration of physiological conditions happens, which causes an alteration of the local immunity, this results in their overgrowth causing the infection with its symptoms. Other less common species, also called non-albicans, such as C. glabrata, C. tropicalis and C. krusei, represent 10% of candidiasis infections and an increase in their frequency and in the resistance to usual treatment have been recorded recently.
There are well-known triggers such as poorly controlled diabetes, the use of antibiotics, pregnancy, taking contraceptives, immunodepression, humidity, etc. These and any other circumstance can promote the multiplication of this type of fungi that, up until now, were asymptomatic.
In bacterial vaginosis, infections are caused by bacteria, mostly by the bacterium Gardnerella vaginalis, which also tends to be a regular vagina commensal and which causes the infection when it develops in excess. It is not known exactly what it takes to develop this deviation from the normal balance of the microbiota (usual and beneficial bacteria of the vagina) but one hypothesis is that it is a natural form of response to sexual intercourse, where the mixture of ejaculation and vaginal discharge generated during intercourse raise the pH in an attempt to protect the sperm cells. This new pH would promote the proliferation of Gardnerella vaginalis.
Sometimes vulvar and/or vaginal inflammation, are not of infectious aetiology, and may have an irritative or allergic origin.
Vulvovaginal candidiasis usually causes many symptoms: whitish vaginal secretion with lumps (with an appearance of cottage cheese or of sour milk), pruritus (itching), burning, vulvar inflammation, reddened vaginal mucosa, skin lesions in the vulva and perineum, and sometimes also discomfort when urinating and when having sexual intercourse.
However, the vast majority of cases of bacterial vaginosis do not cause inflammatory symptoms, so it is clinically characterised by an increase in vaginal secretions which makes it more watery and foul-smelling ("fish" smell), and which is accompanied by limited additional vulvovaginal symptoms. Due to its discrete symptoms its identification is more difficult, and it is striking to know that 50% of patients with vaginosis are asymptomatic and it is a causal finding in gynaecological consultations.
The diagnosis of all of them is usually carried out via the symptoms that the patient presents and the examination. When there are doubts about the causative agent it is usually carried out by performing a fresh examination or a vaginal culture and, therefore, being able to treat it in the most correct way possible.
The aim of treatment is to relieve symptoms, which is why all symptomatic women should be treated.
Vulvovaginal candidiasis which does not produce symptoms, and is diagnosed as a causal finding, does not generally require treatment.
Bacterial vaginosis per se is not dangerous, although it can be associated with other complications if it is not treated. In pregnant women, it increases the risk of preterm birth and in non-pregnant women it increases the risk of other infectious diseases, such as herpes, chlamydia and endometritis. In patients who are going to undergo surgical procedures through the vaginal route (hysterectomy, curettage for abortion) the presence of bacterial vaginosis increases the risk of infectious complications. For this reason, the treatment of patients with a diagnosis of bacterial vaginosis is advised, even if they are asymptomatic, if they are going to undergo vaginal surgical procedures. In the remaining cases of asymptomatic vaginosis, the gynaecologist will assess whether or not treatment is needed.
These types of infections (candidiasis and bacterial vaginosis) tend to disappear with topical treatments in the form of vaginal ovules and/or vulvar creams, antifungals are used for candidiasis and antibiotics for bacterial vaginosis. On rare occasions, oral treatment needs to be added.
In addition to the treatment with antifungals or antibiotics, gynaecologists increasingly tend to add probiotics as a coadjuvant (usually Lactobacillus) via the vaginal or oral route, since they help to repopulate the normal vaginal flora with beneficial bacteria that will help to prevent a relapse of the infection. These Lactobacillus are the main microorganisms responsible for the maintenance of the balance in the vaginal ecosystem, up to the point that they are the dominant species in 70% of healthy women. At the moment, it is considered that the alterations of the vaginal microbiota are the main precursor to vaginal infections.