Certain skin conditions come with very visible symptoms that can be embarrassing for the people who have them. Tinea versicolor is a skin condition caused by yeast overgrowth on the skin. It appears as a rash on the arms, legs, neck, chest and back. Some people also develop a rash on the face. The rash can either lighten or darken the skin.
Dark-skinned people typically experience a loss of color in the skin affected by the rash, while light-skinned people experience a darkening of the skin. This makes the rash very visible, especially when it spreads to areas like the arms, legs and face, which are often exposed. The embarrassment can worsen when the affected areas begin to form flakes.
It is important to understand exactly what tinea versicolor is in order to understand how to manage it. Although is easily treated, some people may experience reinfection if they do not fully treat their condition. Click here for information about our #1 recommended treatment for tinea versicolor.
What is Tinea Versicolor?
Tinea versicolor is a fungal infection. It is most often caused by a yeast called Malassezia globosa, although a small percentage of cases are caused by a slightly different yeast called Malassezia furfur. These yeasts live on the skin of humans and animals, and normally cause no problem for their hosts. However, when the yeast becomes more numerous, some skin conditions may develop. The yeasts in the Malassezia genus are responsible for several different skin conditions; in fact, M. globosa itself also causes dandruff when an overgrowth occurs on the scalp as opposed to the skin. Some dandruff treatments are also effective against tinea versicolor. For more information about using anti-dandruff products to treat tinea versicolor, read our article on Tinea Versicolor Treatment Methods.
M. globosa and other Malassezia yeasts feed on fats, so the areas they tend to grow in are areas with high levels of sebum. Sebum, a waxy substance produced by the skin, has a high lipid content and is produced by sebaceous glands. Sebaceous glands are found in high numbers on the face, scalp and upper part of the body. These are the areas of the skin most affected by tinea versicolor, since there is an abundance of sebum in these areas.
Tinea versicolor begins when the yeast begins to extend long filament structures called hyphae over the top layer of the skin. This is usually harmless, since the outermost layers of skin are comprised of dead skin cells over a living layer of tissue that the fungus cannot penetrate. When the yeast extends its hyphae over the skin, the skin discoloration that is the hallmark of tinea versicolor may begin to develop. This is because as the yeast begins to reproduce, it releases ever-larger amounts of a chemical that interferes with melanocytes. Melanocytes give skin its pigment, and a disruption of the melanocytes' normal function can cause a lightening or darkening of the skin where the yeast grows.
A more bothersome form of tinea versicolor begins when the fungus is able to penetrate into the living layers of skin tissue that are normally protected by the epidermis, which is the outer layer of skin that usually prevents infections from occurring. The yeast that causes tinea versicolor is an opportunistic pathogen. This means that although it normally does not cause infections or serious problems, it may cause an infection when its environment changes. Many microorganisms that live in the human body can cause an opportunistic infection under certain conditions.
Even when tinea versicolor is present, it may not cause any issues other than superficial changes in the skin's appearance. While embarrassing, this is often harmless. However, openings in the skin such as cuts or scratches can allow the yeast to enter deeper layers of skin tissue, causing the yeast to reproduce more quickly. People with conditions such as eczema or other conditions that cause itching should take special care not to scratch around areas affected by tinea versicolor, since opening the skin could prolong infection and make it more difficult to cure. Tinea versicolor itself can cause mild itching, but scratching will only exacerbate the condition. Using a topical anti-itch medication can alleviate the itching until you can treat the tinea versicolor.
The Malassezia yeasts usually do not engage in the rapid reproductive behavior that causes tinea versicolor, but certain conditions can induce this behavior. The people who develop tinea versicolor tend to be teenagers and young adults. This is because people in their teens and early twenties often experience a high level of hormonal activity. Hormonal fluctuations during this time often cause the sebaceous glands to become more active, providing more food for the yeasts that cause tinea versicolor.
Who Gets Tinea Versicolor?
People who sweat a lot or who live in tropical or subtropical climates are also more likely to develop tinea versicolor. Sweating releases more sebaceous material onto the skin, providing even more food for the yeast and allowing them to reproduce even faster. The warm and moist environment on the skin provides an ideal place for the yeast to reproduce. People living in warm or hot climates may experience problems with tinea versicolor year-round. If the winter months bring cool, dry conditions, tinea versicolor may subside but return during the hot, humid summer months.
It is important to understand that tinea versicolor is not contagious. The fungi that cause tinea versicolor are present on everyone's skin, so transmission of some of these fungi through skin-to-skin contact is not enough to pass tinea versicolor from one person to another. Tinea versicolor occurs because of unknown factors that cause the yeast to hyphaenate and reproduce more readily and aggressively. Changes in a person's body may also alter their body's environment and further complicate the condition.
Although people within the same family may experience tinea versicolor at some point in their lives or even at the same time, this is not because of contagion but rather partially influenced by genetic factors. Hormonal function is inherited from one or both parents: when a person is predisposed to developing oily skin because of hormonal factors, they are likely to pass this trait on to their children. Excessive sweating is also frequently hereditary. People within the same household also experience the same climate conditions. All of these factors promote yeast growth on the skin and make a person much more likely to develop tinea versicolor. The article Tinea Versicolor Risk Factors explains more about heredity and other factors in the development of tinea versicolor.
It is recommended that you seek professional advice before beginning treatment for any medical conditions, including tinea versicolor. The American Academy of Dermatology website can help you locate a dermatologist in your area here.