Vaginal Yeast Infection

Vaginal yeast infection is a disorder characterized by inflammation of the vagina and vulva. The inflammation is due to an overgrowth of Candida albicans, a fungus normally present in small amounts in the vagina, the mouth, the digestive tract, and on the skin. Symptoms appear when the balance between the normal microorganisms of the vagina is lost, and the C. albicans population becomes larger in relation to the other microorganism populations, especially Lactobacillus organisms.

Candida albicans photomicrograph. Source: CDC

Other Names

• Vulvovaginal candidiasis
• Vaginal thrush
• Monilia

Symptoms

The most frequent symptoms of yeast infection in women are:

• Itching
• Burning
• Irritation of the vagina.
• Pain with urination
• Pain with intercourse

• Vaginal discharge is not always present and may only be present in small amounts. When present, the discharge is typically thick and white although the characteristics may vary.
• Most male partners of women with yeast infections do not have any symptoms of the infection. Some men, however, have reported temporary rashes and burning sensations of the penis after intercourse if condoms were not used.
• There appears to be a correlation between the yeast count and severity of symptoms in vaginal yeast infection. ^[1]

Causes

Yeast infection may follow a course of antibiotics (particularly tetracycline) that were prescribed for another condition. The antibiotics change the normal balance of organisms in the vagina by suppressing the growth of protective Lactobacillus bacteria.

Infection is common among women who use oral contraceptives or who are pregnant. This is due to the increased level of estrogen in the body. The increased hormone level causes changes in the vaginal environment that make it easier for yeast to grow.

Yeast infections may also occur in association with diabetes or for women who are immunosuppressed (such as those who have AIDS or HIV).

Vaginal candidiasis is transmitted to men after sexual contact with an infected partner. Men develop symptoms such as itching and penile rash in 12% to 15% of cases following intercourse with an infected partner.

Transmission

Although often present in the vagina of healthy women, vaginal yeast infections can also be a result of sexual contact. Since C. albicans is normally present in the vagina, it is difficult to measure or study sexual transmission of C. albicans. One recent study has suggested that sexual behaviors (especially oral-genital contact) can contribute to recurrent yeast infections.^[2]

Diagnosis

• Because few specific signs and symptoms of yeast infections are usually present, health care providers cannot diagnose this condition by a person's medical history and physical examination. Yeast infection can be definitively diagnosed by examining vaginal secretions under a microscope for evidence of yeast.

• One study, however, showed that half of women with vaginitis lacked a definitive diagnosis of candidiasis. ^[3].

This photomicrograph of a vaginal smear identifies Candida albicans while using a wet mount technique.

• Swab results can be misleading because the C. albicans can be present without causing symptoms, and it can only be cultured if a certain amount is present. Swabs from outside the vagina can be negative, even when the yeast is present inside the vagina and there is a typical rash on the vulva.

Recurrent Infection

Some women with recurring vulvovaginal symptoms appear to be hypersensitive to the candida organism. This is called cyclic vulvovaginitis, which is a recurrent burning and itching sensation that occurs at the same stage of every menstrual cycle. The pain specifically worsens just before or during the menstrual bleeding, or may subside during bleeding. Between cyclical flare-ups, a woman may have no symptoms. Pain can be aggravated by sexual activity and is usually worse the day after intercourse. Vaginal smears and cultures are usually performed to determine the cause, which is often (though not always) recurrent yeast infections. If a culture taken during a symptomatic phase comes back negative, a swab during the asymptomatic phase is usually taken. ^[4]

In other cases, a different species of yeast i.e. a non-albicans candida is found. This is not likely to cause significant vulvovaginitis. Antifungal agents may not completely eradicate the non-albicans candida from the vagina. Fortunately, it tends to disappear in time by itself.

In recurrent cases the swab should be repeated after treatment to see whether Candida albicans is still present

AIDS and Candidiasis

Recurrent episodes of vaginal candidiasis, especially repeat infections that occur immediately following therapy, or a persistent yeast infection that does not respond to therapy, may be an early sign that a woman is infected with HIV.

Both males and females with HIV infection who have developed AIDS may be subject to disseminated infection with candida, including oral candidiasis (in the mouth), esophageal candidiasis (in the esophagus), and cutaneous candidiasis (on the skin).

Treatment

A number of antifungal vaginal medicines are available to treat yeast infections. Some are now available over the counter. Women can buy antifungal creams to be applied directly to the affected area, tablets to be taken orally, or suppositories (butoconazole, miconazole, clotrimazole, and tioconazole) for use in the vagina.

Because it is difficult to know the difference between bacterial vaginosis, trichomoniasis, and yeast infections on the basis of symptoms alone, a woman with vaginal symptoms should see her health care provider for an accurate diagnosis before using over-the-counter antifungals.

Women who have chronic or recurring yeast infections may need to be treated with vaginal creams or oral medicines for long periods of time. HIV-infected women can develop severe yeast infections that often do not respond to treatment.

Prevention

Some preventive measures that may decrease the risk of developing a vaginal yeast infection:

• Avoiding the use of douches
• Avoid scented hygiene products like bubble bath, sprays, pads and tampons
• Changing tampons and pads often during the menstrual cycle
• Not wearing tight underwear or clothes made of synthetic fibers.
• Wearing cotton underwear and pantyhose with a cotton crotch.
• Changing out of wet swimsuits and exercise clothes as soon as possible

Since there is a strong connection between nutritionand the immune system, many experts have advocated nutritional approaches to prevent and treat conditions like candidiasis. Sugar, yeast, dairy, wheat, and alcohol may promote the growth of yeast.^[5]. Nutritionists recommend limiting these foods to decrease the risk and/or severity of yeast infections. Although most studies to date have not found any direct connection between these factors and vaginal yeast infections.^[6]

Probiotics are various strains of bacteriathat, when present, confer a health benefit. The most well known probioticsare strains of Lactobacillus that naturally inhabit the colon and vagina. Lactobacillus species found in yogurt have been cited specifically as useful for vaginal problems, especially vulvolvaginal candidiasis that develops after antibiotic treatment. ^{[7] [8]} However, a recent study concluded that the use of oral or vaginal forms of lactobacillus to prevent post-antibiotic vulvovaginitisis not supported by the evidence.^[9]

Cranberry juice is also touted as a prevention for vaginal yeast infections. There is a lack of scientific evidence behind this recommendation. In fact, a study done in 1968 ^[10] showed that cranberry juice had no effect on Candida albicans.

Chances of Developing Vaginal Yeast Infection

Incidence

Health experts estimate that approximately 75% of women will have at least one yeast infection with symptoms during their lifetime; 40%-45% will experience two or more episodes.^[11]

Risk Factors

Many things can change the acidity of the vagina and boost the chances of developing a vaginal yeast infection. These include:

• Stress
• Lack of sleep
• Illness
• Poor diet
• Large intake of sugary foods
• Pregnancy
• Taking birth control pills
• Taking antibiotics
• Taking steroid medicines
• Diseases such as poorly-controlled diabetes and HIV infection

Clinical Trials

• Vaginal Yeast Infection Clinical Trials
• Biomedical Research Alliance of New York: Bacterial Vaginosis/Vulvovaginal Candidiasis Infections

Research

Medical research on vulvovaginal candidiasis (VVC) comprises three main areas of focus:

• The epidemiology of VVC and risk factors for VVC (including pregnancy and diabetes)
• The mechanisms and efficacy of antifungal treatment of VVC
• The host-pathogen interactions in VVC, especially in immunosuppressed patients (such as those with AIDS)

Other Resources

There are several commercially available test kits for home diagnosis of vaginal yeast infection. It is important to visit a health care professional if symptoms change or worsen of if self-treatment is ineffective.

• Savvycheck Yeast Test
• Vagisil Screening Kit

References

1. ↑ Hopwood V, Crowley T, Horrocks CT, Milne JD, Taylor PK, and Warnock DW. Vaginal candidosis: relation between yeast counts and symptoms and clinical signs in non-pregnant women. Genitourin Med. 1988; 64(5): 331–334. Abstract
2. ↑ Reed B, Zazove P, Pierson C, Gorenflo D, Horrocks J. Candida Transmission and Sexual Behaviors as Risks for a Repeat Episode of Candida Vulvovaginitis. Journal of Women's Health. 2003;12(10): 979-989. Abstract | Full Text
3. ↑ Schaaf VM, Perez-Stable EJ, Borchardt K. The limited value of symptoms and signs in the diagnosis of vaginal infections. Arch Intern Med. 1990;150(9):1929-33. Abstract
4. ↑ DermNetNZ: Cyclic Vulvovaginitis Information Page
5. ↑ Donders GG, Prenen H, Verbeke G, Reybrouck R. Impaired tolerance for glucose in women with recurrent vaginal candidiasis. Am J Obstet Gynecol. 2002;187:989–93. Abstract
6. ↑ Ehrström S, Yu A, Rylander E. Glucose in vaginal secretions before and after oral glucose tolerance testing in women with and without recurrent vulvovaginal candidiasis. Obstet Gynecol. 2006 Dec;108(6):1432-7. Abstract | Full Text
7. ↑ Mombelli B, Gismondo MR. The use of probiotics in medical practice. Int J Antimicrob Agents. 2000;16: 531-6. Abstract
8. ↑ Nyirjesy P, Weitz M, Grody T, Lorber B. Over-the-counter and alternative medicines in the treatment of chronic vaginal symptoms. Obstet Gynecol. 1997;90: 50-3. Abstract
9. ↑ Pirotta MJ, Gunn P, Chondros S, et al. Effect of lactobacillus in preventing post-antibiotic vulvovaginal candidiasis: a randomised controlled trial].BMJ. 2004; 329:548-550. Abstract
10. ↑ Swartz J, Medrek T. Antifungal properties of cranberry juice. Appl Microbiol. 1968; 16(10): 1524–1527. Abstract | PDF
11. ↑ CDC: Candidiasis

External Links

CDC: Candidiasis

American College of Obstetricians and Gynecologists