Vulvovaginitis: Candidiasis and Bacterial Vaginosis
Vulvovaginal infections are a common reason for consultation, accounting for 20% of gynaecological consultations. 75% of women experience one episode of symptomatic vulvovaginitis during their lifetime and 40-50% experience at least one second episode.
Vulvovaginitis is inflammation of the vaginal mucosa and vulvar skin, although both areas are not always affected simultaneously.
Causes
Candidal vulvovaginitis is caused by different species of fungi, mainly Candida, with Candida albicans responsible for 90% of
episodes of vulvovaginal candidiasis. These yeasts usually live in small quantities in the vagina without causing symptoms, but when there is a change in physiological conditions, leading to an alteration in local immunity, they overgrow, causing infection and symptoms. Other less common species, also known as non-albicans, such as C. glabrata, C. tropicalis and C. krusei, account for 10% of candidiasis cases and have recently seen an increase in frequency and resistance to standard treatment.
There are well-known triggering factors such as poorly controlled diabetes, antibiotic use, pregnancy, contraceptive use, immunosuppression, humidity, etc. These and other circumstances can promote the multiplication of this type of fungus, which until then was asymptomatic.
In bacterial vaginosis, infections are caused by bacteria, mostly Gardnerella vaginalis, which is also a common commensal of the vagina and which, when it develops in excess, causes infection. It is not known exactly what causes this deviation from the normal balance of the microbiota (normal and beneficial bacteria in the vagina), but one hypothesis is that it is a natural response to sexual intercourse, where the mixture of ejaculate and vaginal fluid generated during intercourse raises the pH in an attempt to protect the sperm. This new pH would favour the proliferation of Gardnerella vaginalis.
Sometimes, vulvar and/or vaginal inflammation is not infectious in origin, but may be caused by irritation or an allergy.
Symptoms
Candidal vulvovaginitis usually causes many symptoms: whitish vaginal discharge with lumps (resembling cottage cheese or curdled milk), pruritus (itching), burning, vulvar inflammation, reddened vaginal mucosa, skin lesions on the vulva and perineum, and sometimes discomfort when urinating and during sexual intercourse.
However, bacterial vaginosis does not usually cause inflammatory symptoms, so clinically it is characterised by an increase in vaginal discharge that becomes more watery and malodorous (smelling like fish), accompanied by few additional vulvovaginal symptoms.
Due to its mild symptoms, it is more difficult to identify, and it is striking that 50% of patients with vaginosis are asymptomatic and it is a chance finding in gynaecological consultations.
Diagnosis
The diagnosis of all of these conditions is usually made based on the patient's symptoms and examination. When there is doubt about the causative agent, a sample should be taken for a fresh examination or vaginal culture so that the most appropriate treatment can be given.
Treatment
The aim of treatment is to relieve symptoms, so all symptomatic women should be treated.
Vulvovaginal candidiasis that does not cause symptoms and is diagnosed as a chance finding does not usually require treatment.
Bacterial vaginosis per se is not dangerous, although it can be associated with other complications if left untreated. In pregnant women, it increases the risk of preterm delivery, and in non-pregnant women, it increases the risk of other infectious diseases such as herpes, chlamydia, and endometritis. In patients undergoing vaginal surgical procedures (hysterectomy, curettage for abortion), the presence of bacterial vaginosis increases the risk of infectious complications. For this reason, it is advisable to treat patients diagnosed with bacterial vaginosis, even if they are asymptomatic, if they are undergoing vaginal surgical procedures. In other cases of asymptomatic vaginosis, the gynaecologist will assess whether treatment is necessary.
These types of infections (candidiasis and bacterial vaginosis) usually disappear with topical treatments in the form of vaginal ovules and/or vulvar creams. Antifungals are used for candidiasis and antibiotics for bacterial vaginosis. In rare cases, oral treatment may be necessary.
In addition to treatment with antifungals or antibiotics, gynaecologists increasingly tend to add probiotics (usually Lactobacillus) vaginally or orally as an adjunct, as they help repopulate the normal vaginal flora with beneficial bacteria that will help prevent a relapse of the infection. These Lactobacillus bacteria are the main microorganisms responsible for maintaining balance in the vaginal ecosystem, to the extent that they are the dominant species in 70% of healthy women. Currently, alterations in the vaginal microbiota are considered to be the main precursor to vaginal infections.