These are fungi that resemble yeast found in the intestine, on the skin, and in the mucous membranes of the mouth. A change in environment favorable to the fungus, combined with the weakening of the host's defenses, can allow the microorganism to increase in number and cause the infection. This allows the fungus to grow, thus causing the infection. Altered hormone levels in the body, such as those that occur during pregnancy and while taking contraceptive pills, also make it easier for the fungi to grow. The infection may accompany other disorders, such as AIDS, diabetes mellitus, leukemia, or conditions that require treatment with corticosteroid drugs, all of which lower the body's immunity to Candida albicans.
Similar conditions occur in the vagina, a common area for the infection in women.
There are various areas on the skin that can become infected. Candidiasis may occur as a form of diaper rash in babies, if the buttocks are allowed to remain moist with urine. Skin infections are treated with fungicidal creams or lotions, and vaginal infections may be treated with suppositories. The rare internal forms of candidiasis are, under the care of a physician, treated with potent fungicidal drugs.