Have you noticed vaginal itching, soreness, redness, swelling, dry, cracked skin, and a thick, white, vaginal discharge that resembles cottage cheese?  Or have you noticed a few of these symptoms, while others are absent?
You might well assume — or at least have a strong suspicion — that you are dealing with a vaginal yeast infection, as an estimated three quarters of all women do at least once in their lives . If you're pretty sure you know what you are dealing with, you may even turn to natural or pharmacologist yeast infection treatment at home. Natural yeast infection remedies such as garlic capsules and yogurt don't require any prescription, after all, and neither do the most popular antifungal agents, medications such as clotrimazole, miconazole, and tioconazole .
What if you're not absolutely sure that you are indeed dealing with a vaginal yeast infection, on the other hand? These SteadyHealth readers know the feeling:
- "Why is my vagina itching? I'm only 13 and I don't know what is happening, there white discharge with some small weird bits in it. Can it be a yeast infection?"
- "I've been having recurring yeast infections. I'm on birth control and I can usually pinpoint when I'm going to get one. I haven't gotten it looked at, so it very well could be something else. Should I be worried about any sort of STD?"
- "A few weeks ago I had gotten strep throat. When I got the medicine for strep I ended up getting a side effect where my vagina was itchy. I thought it was a yeast infection. I woke having to frequently use the bathroom. Is this a really bad yeast infection or an STI?"
These are just three examples of women who posted on our community boards questioning whether they had yeast infections or something else, but they're interesting. One noticed itching, a symptom commonly associated with vaginal candidiasis. Another has a history of recurrent yeast infections and is on birth control, a known risk factor for yeast infections , and additionally thinks she can pinpoint the symptoms. The third was treated for strep throat — presumably with antibiotics, which represent another risk factor for yeast infections .
Could My 'Yeast Infection' Symptoms Be Another Kind Of Vaginitis?
Vaginitis is a general term for vaginal infections or inflammation. The most common causes are candidiasis, trichomoniasis, and bacterial vaginosis , and atrophic vaginitis, caused by estrogen insufficiency, also deserves an "honorable mention".
Let's briefly examine the symptoms most commonly associated with each of these.
- Trichomoniasis is a sexually transmitted disease caused by the tiny parasite Trichomonas vaginalis. Symptoms typically include irritation of the vulva (redness, burning, swelling), a green-yellow vaginal discharge that may have a fishy odor, and sometimes pain while urinating. Not all women with trichomoniasis experience symptoms, however, and even in those who do, the symptoms may be less specific. This is why the Centers for Disease Control and Prevention recommends testing for trich in all women who seek care for abnormal vaginal discharge.
- Bacterial vaginosis is an overgrowth of anaerobic bacteria in the vagina. It is characterized by a thin, white, dark, gray, or green discharge — not the thick, white discharge associated with yeast infections. A fishy smell may again be present, and women with bacterial vaginosis will sometimes also be itchy in the genital area.
- Atrophic vaginitis is caused by a lack of estrogen, and can present with abnormal vaginal discharge, burning, dryness, and itching. [6,7]
The CDC notes that the symptoms typically associated with vaginal candidiasis — itching, a sore vagina, abnormal vaginal discharge, and sometimes pain while urinating and having sex — aren't specific to that condition .
I Think I Have A Yeast Infection But I'm Not Sure: What Now?
If you are pretty sure you have a vaginal yeast infection, especially if you've had one before and know from experience what that felt like, you might well be right. Research shows that "patient self-diagnosis of 'another yeast infection' is one of the best predictors for a positive culture, after all. The same study noted that clinical diagnosis yields unreliable results, however. (Yes, that means that women with a history of yeast infections are more likely to know what's wrong with them than doctors are, without further testing.) 
The ways to determine whether you really have a vaginal yeast infection include:
- A KOH test for Candida albicans and other yeast species. This is also known as a potassium hydroxide preparation. Relevant samples are collected, bathed in potassium hydroxide, left to percolate for a bit, and examined under a microscope.
- A gram stain, during which a swab is taken and it will be examined under the microscope with the help of dyes and heat.
- A yeast culture, during which your sample is followed in a lab setting over several days. 
The Bottom Line
One study described the way in which vaginal infections are often diagnosed as "throwing the dice" — nothing more than a gamble, in other words. Vaginal candidiasis was, perhaps frighteningly, found to be the most frequently misdiagnosed vaginal infection — a full 77 percent of cases diagnosed as such turned out to be something different, among the women the researchers studied.