Even common mouth and vaginal yeast infections can cause critical illness and can be more resistant to normal treatment. In women, yeast infections are the second most common reason for vaginal burning, itching, and discharge. Yeasts are found in the vagina of most women and can overgrow if the environment in the vagina changes. Antibiotic and steroid use is the most common reason for yeast overgrowth. But pregnancy, menstruation, sperm, and birth control pills also can contribute to getting a yeast infection.
Yeast infections are more common after menopause.
In people who have a weakened immune system because of cancer treatments, steroids, or diseases such as AIDS, candidal infections can occur throughout the entire body and can be life-threatening. The blood, brain, eye, kidney, and heart are most frequently affected, but the candidal fungus also can grow in the lungs, liver, and spleen. These infections enter into the bloodstream through breakdowns or cuts in the skin or mucous membranes. Candidal organisms may build up in an area because of frequent use of strong antibiotics, which kill the bacteria that normally keep it under control. Use of devices implanted in the skin such as urinary catheters and IV ports also provide access for the yeast to enter the body.