What VVC is
Vulvo-vaginal candidiasis is also known as 'Thrush' or 'Vaginal Yeast Infection'. It is an overgrowth of a yeast that lives naturally in a woman’s vagina and gut. The yeast is of a type called candida (hence candidiasis) and the overgrowth occurs in the vagina and area of skin between a woman’s legs called the vulva (hence vulvo-vaginal). The most common type of candida to cause thrush is called candida albicans. However, there are other less common types of candida and candida glabata and candida tropicalis are the names of two of them.
How VVC develops
Thrush is not a sexually transmitted disease but aovergrowth of the yeast that lives naturally in the vagina. It is true that VVC is more common after sexual intercourse. However, this is as unprotected sexual intercourse provides a better environment for the yeast to become overgrown not because the candida is being transmitted from the man to the woman. It is possible to develop Thrush without ever having sexual contact.
How VVC presents
Vulvo-vaginal candidiasis is a self-limiting condition that causes no long-term harm. However, it may cause symptoms that are uncomfortable. These include itching, burning, soreness and dryness. Thrush can cause stinging when passing urine (called dysuria) and discomfort during intercourse (called dyspareunia). Sometimes women have a curd-like white discharge. No symptom is specific to Thrush and a woman may have VVC without any of these symptoms.
Women who develop VVC
Over 75% of women develop vulvo-vaginal candidiasis at some point in their life. On most occasions it develops without any obvious cause. However, it is more likely to occur in association with the following;
- Antibiotics – A course of antibiotics can predispose to VVC by killing the bacteria that live naturally in the vagina. This allows the candida that also live naturally in the vagina to become overgrown as yeasts are not killed by antibiotics.
- Sexual intercourse – Unprotected sexual intercourse increases the likelihood of developing VVC. This is probably due to the acidity of sperm providing an ideal environment for yeast to grow.
- Diabetes – Diabetic women who have poor sugar control are more likely to develop candida. This is thought to be associated with sugar containing cells in the vagina providing the ideal environment for Thrush to grow.
- Estrogens – Estrogens are hormones that occur naturally in the ovaries. High levels occur in pregnancy. They can also be high in women who take the pill and hormone replacement therapy (HRT). Pregnant women, women on the pill, and women on HRT are more likely to develop Thrush.
- Cunnilingus – Receptive oral sex is thought to provide an ideal environment for VVC.
- Vaginal contraceptives – A vaginal contraceptive called the sponge is associated with Thrush. This form of contraceptive is no longer readily available.
- Immunodepressed women – Immunodepressed women are those whose immune systems are not working properly. AIDS is a condition well known to cause women to be immunodepressed. More commonly, immundepression occurs after the administration of drugs such as transplant drugs, steroids, or chemotherapy. Immunodepressed women are more likely to develop VVC.
- Miscellaneous – A number of miscellaneous situations are thought to predispose to Thrush. These include the use of certain bubble baths, vaginal douching, long warm baths, and non-cotton underwear.
Types of VVC
There are four main types of vulvo-vaginal candidiasis. These are;
- Isolated VVC – This is the most common type and occurs in most women on an occasional basis.
- Relapsed VVC – This is when the Thrush returns within a few weeks of treatment. It is due to inadequate treatment of the original episode of thrush and can normally be cured by a longer course of therapy.
- Resistant VVC – This is extremely rare and occurs when the candida has developed resistance to drugs that are usually used to treat it.
- Recurrent VVC – This is defined as four or more episodes of VVC in one given year.
How VVC is diagnosed
Thrush is confirmed by the growth of yeast in the laboratory following a vaginal swab. However, this method takes a few days to provide a result and most doctors treat women with clinical evidence of VVC empirically, without a confirmed diagnosis by a vaginal swab. If a woman is receiving treatment for relapsed, resistant, or recurrent VVC, it is usual for a confirmatory swab to be obtained. Some times bacterial vaginosis (BV) can be confused for thrush.
Treatment for VVC
Treatment is usually in the form of a class of drugs called azoles. These can be given vaginally in the form of a pessary or cream or both. The names of some vaginal azoles licensed for the treatment of VVC include clotrimazole (Canestan®), econazole (Ecostatin® & Gyno-Pevaryl®), miconazole (Gyno-Daktrin®), fenticonazole (Lomexin®), ketoconazole (Nizoral®), and nystatin (Nystan®). In the first instance, a single pessary at night is normally enough to cure the Thrush. If VVC returns shortly after treatment, a longer course of therapy is required. Oral azoles are also available for treatment of thrush. The names of some oral azoles licensed for the treatment of VVC include fluconazole (Diflucan®) and itraconazole (Soporanox®). Preparations of Diflucan® and Canestan® for VVC can be bought over the counter at chemists in the UK.
MOST VAGINAL PREPARATIONS FOR THE TREATMENT OF THRUSH WEAKEN THE LATEX IN CONDOMS AND CONTRACEPTIVE DIAPHRAGMS.
If no other form of contraception is being used, women should refrain from sexual intercourse during treatment unless pregnancy is desired.
Resistant VVC is extremely rare. Drugs that have been used for it’s treatment include, the contraceptive depot injection of medroxyprogesterone acetate (DepoProvera®), vaginal application of boric acid, and flucytosine (Ancotil®). Ancotil® tablets are only available on a named patient basis and are not readily available.
Prevention of VVC
Recurrent thrush can be prevented by a number of measures. These include taking azoles during antibiotic therapy, ensuring any diabetes is well controlled, using condoms during intercourse, and avoiding warm baths and other miscellaneous causes of Thrush. Natural yoghurt helps to prevent against thrush by restoring the bacteria called lactobacilli to the vagina. This can be inserted into the vagina but is just as effective if eaten. Only few yoghurts are natural live yoghurts and it is important to read the label carefully. A few lactobacilli containing drinks are now available also such as Yakult® and Actimel®. These probably prevent against thrush also. Some women who have recurrent Thrush are advised continuous azole therapy. This involve a dose of an azole drug one a week or even one a day for six months.