Yeast and the skin
Published: Wed, October 27, 2010 by Dr. Clive Anderson
Tinea versicolor or more commonly Liver spots is a common skin infection due to an overgrowth of yeast on the skin. The yeast is known as Malassezia furfur and is normally present on the skin of most persons. Anyone can develop a yeast infection of the skin.
The yeast normally lives in the pores of the skin and thrives in oily areas such as neck, upper chest and back, consequently the infection affects the skin of the chest, back and shoulders most commonly. The face may also be affected.
Tinea versicolor or more commonly Liver spots is a common skin infection due to an overgrowth of yeast on the skin. The yeast is known as Malassezia furfur and is normally present on the skin of most persons. Anyone can develop a yeast infection of the skin.
The yeast normally lives in the pores of the skin and thrives in oily areas such as neck, upper chest and back, consequently the infection affects the skin of the chest, back and shoulders most commonly. The face may also be affected.
The condition is not considered contagious, as the causative organism is present on all skins. . In most persons the presence of the yeast on the skin does not cause any visible changes. In some individuals the yeast grows more actively on the skin and causes a rash. The reasons why the yeast affects the skin of some persons while remaining as normal flora in others are not known.
Tinea versicolor usually produces few symptoms. Only rarely is there itching. The yeast however prevents the process of pigmentation. This results in patches of skin with less pigment that the surrounding areas of normal skin. These patches appear as pale or white spots; sometimes the spots may be brown coloured. These patches tan less than the surrounding normal skin and so become more visible with sun exposure. Often fine scaling is visible over the spots.
During the hotter months the frequency of this skin infection increases. Tinea versicolor occurs worldwide, with a prevalence of over 50% in hot countries and only 1% in colder climes like Sweden. Although the skin colour changes are more easily seen in dark skinned individuals the condition occurs in all races. The disease is most common in the age groups 15-24, occurring rarely before puberty and after age 65 years.
Although the light and dark coloured spots can resemble other skin diseases, a Dermatologist easily makes the correct diagnosis. The doctor may do a skin scarping and examine the scales under a microscope for the presence of the yeast. Under a special light in the Dermatologists office the yeast fluoresces a golden yellow colour.
Tinea versicolor may present in three forms:
- The most common form is a light coloured scaly spot over the chest and back. The spots may coalesce into larger patches.
- The second form occurs less frequently appearing on the face and arms
Tinea versicolor is treated with topical or oral medications.
The topical medications include shampoos, creams or lotions applied directly to the skin. Therapy taken by mouth is often preferred by patients because of its convenience and the widespread perception that it is more effective. Because of interactions with other medications and possible side effects oral therapy has to be carefully supervised. Diet has so far not proved successful in affecting the course of the condition or the likelihood of recurrences.
It is important to remember that while the yeast is easily eradicated from the skin the colour changes take weeks to return to normal.
Recurrences are common.
