Candidiasis (candidosis, moniliasis, yeast infection) is infection caused by several species of Candida, especially Candida albicans.
Candida is normally present on the skin, in the intestinal tract, and, in women, in the genital area. Usually, Candida in these areas does not cause problems. However, the fungi sometimes cause infection of the skin (see see Candidiasis), the mucous membranes of the mouth (see see Discomfort and see see Gingivitis Due to Infections), or vagina (see see Overview of Vaginal Infections). Such infections can develop in people with a healthy immune system, but they are more common or persistent in people with diabetes, cancer, or AIDS and in pregnant women. Candidiasis is also common among people who are taking antibiotics because the antibiotics kill the bacteria that normally compete with Candida, allowing Candida to grow unchecked.
Some people, mainly those with a weakened immune system, develop candidiasis that spreads through the bloodstream (called candidemia) to other parts of the body, such as the heart valves, spleen, kidneys, and eyes. Without treatment, this infection progresses.
Infection of the mouth (thrush or trench mouth) causes the following:
Patches in the esophagus cause pain during swallowing.
When the skin is infected, a burning rash develops. Some types of diaper rash are caused by Candida.
If the infection spreads to other parts of the body, it is more serious. It can cause fever, a heart murmur, enlargement of the spleen, dangerously low blood pressure (shock), and decreased urine production. An infection of the retina and inner parts of the eye can cause blindness. If the infection is severe, several organs may stop functioning, and death can occur.
Many candidal infections are apparent from the symptoms alone. To confirm the diagnosis, a doctor must identify the fungi in a sample viewed under a microscope. Samples of blood or other infected tissues may be sent to a laboratory to be cultured and examined to identify the fungi.
Candidiasis that occurs only on the skin or in the mouth or vagina can be treated with antifungal drugs (such as clotrimazole and nystatin) that are applied directly to the affected area. A doctor may prescribe the antifungal drug fluconazole to be taken by mouth.
Candidiasis that has spread throughout the body is usually treated with amphotericin B given intravenously. Other antifungal drugs—fluconazole and related drugs (posaconazole and voriconazole) or caspofungin and related drugs (micafungin and anidulafungin)—are also effective.
Candidiasis is more serious and less responsive to treatment in people with certain disorders, such as diabetes. In people with diabetes, controlling blood sugar levels facilitates cure of the infection.
Last full review/revision October 2008 by Alan M. Sugar, MD