Candidiasis is infection with the yeast Candida.
Candidiasis tends to occur in moist areas of the skin.
This skin infection may cause rashes, scaling, itching, and swelling.
Doctors examine the affected areas and view skin samples under a microscope or in a culture.
Antifungal creams or antifungal medications given by mouth usually cure candidiasis.
(See also Overview of Fungal Skin Infections.)
Yeast is a type of fungus.
Candida is a yeast that normally resides on the skin and in the mouth, digestive tract, and vagina and usually causes no harm. Under certain conditions, however, Candida can overgrow on mucous membranes and moist areas of the skin. Typical areas affected are the lining of the mouth, the groin, the armpits, the spaces between fingers and toes, on an uncircumcised penis, under the breasts, the nails, and the skinfolds of the stomach. Candida can also cause infections in other areas of the body such as the mouth, esophagus, and vagina (see also Candidiasis).
Conditions that enable Candida to infect the skin include the following:
Hot, humid weather
Tight, synthetic underclothing
Poor hygiene
Infrequent diaper or undergarment changes, particularly in children and older adults
A weakened immune system resulting from diabetes, HIV infection/AIDS, or use of corticosteroids or other medications that suppress the immune system (including drugs that treat cancer)
Pregnancy, obesity, or use of antibiotics
Other skin disorders such as intertrigo and psoriasis
People taking antibiotics may develop candidiasis because the antibiotics kill the bacteria that normally reside on the body, allowing Candida to grow unchecked. Corticosteroids or immunosuppressive therapy after organ transplantation can also lower the body’s defenses against candidiasis. Inhaled corticosteroids, often used by people with asthma, sometimes cause candidiasis of the mouth.
In some people (usually people with a weakened immune system), Candida may invade deeper tissues as well as the blood, causing life-threatening systemic candidiasis.
Symptoms of Candidiasis
Symptoms of candidiasis depend on the location of the infection.
Cutaneous candidiasis
Candidiasis infection in skinfolds or in the navel usually causes a bright red rash, sometimes with breakdown of skin. Small pustules may appear, especially at the edges of the rash, and the rash may itch intensely or burn. A candidal rash around the anus may be raw, white or red, and itchy.
Infants may develop a candidal diaper rash.
Image provided by Thomas Habif, MD.
Vaginal candidiasis and penile candidiasis
Vaginal candidiasis (vaginal yeast infection) is common, especially among women who are pregnant, have diabetes, or are taking antibiotics.
Symptoms of a vaginal yeast infection include a white or yellow cheeselike discharge from the vagina and burning, itching, and redness along the walls and external area of the vagina.
Penile candidiasis most often affects men with diabetes, uncircumcised men, or men whose female sex partners have vaginal candidiasis.
Sometimes the rash may not cause any symptoms, but usually the infection causes a red, raw, itching, burning, or sometimes painful rash on the head of the penis.
Thrush
Thrush is candidiasis inside the mouth. The creamy white patches typical of thrush cling to the tongue and sides of the mouth and may be painful. The patches can be scraped off with a finger or blunt object and may bleed when scraped.
Thrush in otherwise healthy children is not unusual, but in adults it may signal a weakened immune system, possibly caused by cancer, diabetes, or human immunodeficiency virus (HIV) infection. The use of antibiotics that kill off competing bacteria increases the risk of developing thrush.
Angular cheilitis (perlèche)
Angular cheilitis is candidiasis at the corners of the mouth, which causes cracks and tiny fissures. It may stem from chronic lip licking, thumb sucking, ill-fitting dentures, or other conditions that make the corners of the mouth moist enough that yeast can grow.
Nail candidiasis
Candidal paronychia is candidiasis in the nail folds or cuticles, which causes painful redness and swelling around the nail. In longstanding infection, the area underneath the nail may turn white or yellow, and the nail plate may separate from the nail bed (onycholysis). This disorder typically occurs in people with diabetes or a weakened immune system or in otherwise healthy people whose hands are subjected to frequent wetting or washing.
Chronic mucocutaneous candidiasis
Chronic mucocutaneous candidiasis causes red, pus-filled, crusted, and thickened areas that resemble psoriasis, especially on the nose and forehead. People who have this condition are also prone to thrush.
Diagnosis of Candidiasis
A doctor's examination of the skin
Examination or culture of scraping sample
Usually, doctors can identify candidiasis by observing its distinctive rash or the thick, white, pasty residue it generates.
To confirm the diagnosis of candidiasis, doctors may scrape off some of the skin or residue with a scalpel or tongue depressor. The scraping sample is then examined under a microscope or placed in a culture medium (a substance that allows microorganisms to grow) to identify the specific fungus.
Treatment of Candidiasis
Antifungal medications applied to the skin or taken by mouth
Measures to keep the area dry
Treatment of candidiasis typically depends on the location of the infection. (See also table Some Antifungal Medications Applied to the Skin (Topical Medications).)
Infections in skinfolds
Vaginal candidiasis is treated with antifungal medications that may be applied as a cream to the affected area, inserted into the vagina as a suppository, or taken by mouth (such as fluconazole).
Candidal paronychia is treated by protecting the area from wetness. Doctors give antifungal medications that are taken by mouth or applied to the skin. These infections are often difficult to treat.
Thrush
Chronic mucocutaneous candidiasis is treated with fluconazole taken by mouth. This medication is taken for a long time.
