Oral thrush is an overproduction of the fungus known as Candida albicans that occurs in the mouth. This fungus lives in the mouths of most people and is kept in check by the healthy bacteria created in the body. A compromised immune system causes the healthy bacteria to die and the fungus to proliferate. Symptoms of oral thrush include velvety, white spots on the tongue, cheeks and roof of the mouth. These lesions may be painful and bleed slightly when scraped. If left untreated oral thrush may spread to the stomach.
Antibiotics
Physicians treat patients with antibiotics for a number of specific conditions. Physicians often give large doses of broad spectrum antibiotics prior to surgery to ward off post operative infections. Physicians also prescribe broad spectrum antibiotics when unsure of the cause of an illness. Broad spectrum antibiotics can kill both healthy bacteria and bad bacteria. This can cause the thrush fungus to accumulate unchecked and lead to a thrush infection.
HIV/AIDS
Human Immunodeficiency virus causes damage and destruction to the immune system, making patients more susceptible to opportunistic infections that the body would normally fight off. Thrush is rare in the early stages of an HIV infection and usually only appears when the T-cells--the key cells in the immune system--drop to very low levels. Candida albicans may spread to the esophagus, causing a condition known as Candida esophagitis. The Center for Disease Control and Prevention considers Candida esophagitis an AIDS-defining illness, meaning that it can be a sign that HIV is progressing to full-blown AIDS.
Cancer
Patients undergoing chemotherapy or head and neck radiation treatments have a greater risk for developing thrush. Chemotherapy and radiation treatments work by targeting rapidly dividing cells, such as cancer cells. Unfortunately, the treatments are unable to distinguish between rapidly dividing cancer cells and other rapidly dividing cells, such as those in the inner lining of the mouth. The skin and mucous membranes often sustain damage during treatment, making the body susceptible to invading organisms. Thrush infections often resolve once treatment has stopped.
