Infection Detection

by Christine Haran

When most women experience genital itching or discharge, they tend to assume they have a yeast infection. Their next step is often quietly buying an over-the-counter product that has been advertised on TV. But genital itching can be a symptom of many other conditions, from other kinds of vaginal infections to sexually transmitted diseases to skin allergies. So unless you are fairly certain you have a bona fide yeast infection, you might want to delay treatment and not waste your money.

"Multiple studies show that symptoms such as itching are not predictive of what kind of condition you have, so a woman can easily have the wrong diagnosis, and there can be repercussions if she treats for the wrong condition," says Linda Eckert, MD, an associate professor in the department of obstetrics and gynecology at the University of Washington in Seattle.

If itching is due to a vaginal infection, it is most likely a case of bacterial vaginosis, a yeast infection or trichomoniasis. Health care providers, such as gynecologists and midwives, say that the best way to distinguish between these infections is not by looking at symptoms, but by testing the vaginal fluid.

Bacterial Vaginosis

The most common vaginal infection is bacterial vaginosis, which occurs when the balance of the microorganisms that normally live in the vagina is thrown off. BV appears to be related to sexual activity, though doctors aren't sure how. Douching also raises risk.

In BV, there is an overgrowth of certain bacteria, such as Gardnerella vaginalis, that leads to low numbers of a protective bacteria called lactobacilli, causing grayish-white vaginal discharge, itching and a fishy odor. When a gynecologist examines the vaginal fluid under a microscope, he or she will be able to see cells coated with BV bacteria. The doctor will also measure the pH of the vagina, which reflects its acidity. In BV, the vaginal pH is higher than normal. Finally, the health care provider should perform a whiff test, where drops of an alkalinizing fluid are added to the vaginal fluid, to see if it produces a fishy odor.

BV is treated with antibiotics. Untreated BV is associated with pelvic inflammatory disease, a condition that can lead to infertility, tubal pregnancy or premature delivery.

Yeast Infections

Yeast infections, the second-most common type of infections, are also due to a change in the vaginal "ecosystem." In a yeast infection, an overgrowth of yeast, usually one called Candida albicans, leads to itching or burning and sometime causes a thick, whitish discharge. Yeast infections are known to occur following a course of antibiotics or the use of oral contraceptives. They are also common in pregnant women, women with diabetes and women who wear underwear or clothes that are tight or made of fabric that does not breathe well, and in women who use feminine hygiene sprays or douches.

"There is a tremendous market for feminine hygiene sprays and douches," says David Soper, MD, a spokesperson for the American College of Ostetricians and Gynecologists vice chair of the department of obstetrics and gynecology at the Medical University of South Carolina in Charleston. "But women are better off not douching or using sprays and instead using mild soaps that don't have detergents."

Health care professionals can identify yeast infections with a physical exam and by examining vaginal fluid under the microscope; they may also choose to send a specimen out for a vaginal yeast culture to confirm an uncertain diagnosis.

Yeast infections are treated with anti-fungal medications, which are available as creams and suppositories, or as a pill called Diflucan. Women with recurrent infections may find relief from a prescription for boric acid that is prepared as a capsule that is inserted into the vagina. Boric acid changes the vaginal pH, inhibiting the growth of yeast.

According to Dr. Soper, women who have had a yeast infection before and who are not at risk for a sexually transmitted disease, can try over-the-counter products if they have the same symptoms. He warns that women should see a health care provider if symptoms don't clear up in a few days, however.