WHAT IS PITYRIASIS VERSICOLOR?Pityriasis versicolor is a harmless skin condition consisting of slightly scaly patches on the body that are a different color than the surrounding skin. The patches in pityriasis versicolor are usually lighter in color than the surrounding skin, but they can also be darker.
This is also where the name comes from, as the term pityriasis is used in dermatology for all kinds of slightly scaly skin conditions, and versicolor means "opposite color." The color changes are caused by yeasts of the Malassezia species , which live on the skin. These yeasts are common on normal skin, but under certain conditions they can cause skin lesions. Pityriasis versicolor is primarily caused by Malassezia globosa and Malassezia sympodialis . The infection is most commonly seen in young adults. Conditions that promote the development of the condition are high humidity, usually in combination with a high ambient temperature, and oily (sebaceous) skin.
 |
 |
| pityriasis versicolor |
pityriasis versicolor |
WHAT ARE THE PHENOMENA?In people with fair skin, pityriasis versicolor can appear as light brown or reddish-brown patches with fine scaling. These patches therefore appear darker than the surrounding fair skin. The color difference is sometimes barely noticeable in winter. When the skin is stretched, flakes break out, a sign that the yeast infection is still active. In summer, sunbathing can reverse the color: the surrounding skin tans, while the affected patches remain brown. At that point, the condition becomes more visible. In people with darker skin, the patches are actually lighter in color than the surrounding normal skin.
The patches can vary in size from a few millimeters to tens of centimeters. They are mainly seen on the trunk and upper arms. They can also merge and merge over large areas of the skin, spreading to the forearms, the backs of the hands, the thighs, and even into the backs of the knees. Especially in tropical climates, the face and scalp are sometimes also affected. The condition is cosmetically disturbing, but causes no other complaints, sometimes a little itching.WHAT IS THE CAUSE OF PITYRIASIS VERSICOLOR?Pityriasis versicolor is caused by a superficial infection of the skin by a yeast of the Malassezia species (formerly also called Pityrosporum ovale). There are several varieties of this yeast. Pityriasis versicolor is primarily caused by the Malassezia globosa and Malassezia sympodialis species. A yeast is a small, single-celled organism that can reproduce by budding. Yeasts of the Malassezia species are always present on normal, healthy skin. These yeasts thrive on the skin's lipid layer. The greatest numbers of yeasts are found on the scalp, the upper part of the trunk, and in body folds. Under certain circumstances, especially in humid and warm conditions, the yeast count can increase and cause problems. Certain conditions, such as (excessive) sweating, diabetes, pregnancy, and a weakened immune system, can also increase the presence of yeasts on the skin. The Malassezia yeasts can cause not only pityriasis versicolor, but also dandruff and a form of eczema called
seborrheic dermatitis .
 |
 |
 |
| Malassezia yeasts |
Malassezia yeasts |
bud-forming yeasts |
Pityriasis versicolor is mainly seen in warm and humid countries. Up to 40% of the population can be affected there. Pityriasis versicolor is also more visible on pigmented skin because the color difference is greater. In the Netherlands, pityriasis versicolor is much less common, affecting approximately 1% of the population. It is mainly present in the summer. Here too, the condition becomes more visible when people sunbathe in the summer: the surrounding skin tans, but the affected areas retain their color. The yeasts produce a substance that inhibits the pigment cells' production of pigment. This causes the color differences.HOW IS THE DIAGNOSIS MADE?The skin lesions are so characteristic that they can usually be recognized visually. Sometimes, a few flakes of skin are scraped off and examined under a microscope to see if yeast globules are visible. Blue ultraviolet light can also be used to examine the skin for a yellow-green color (some Mallasezia yeasts fluoresce yellow-green under ultraviolet light). This is only clearly visible if the consultation room is otherwise completely dark. After treatment with an anti-yeast agent, the yeast globules are no longer visible.
 |
Yeast globules
under microscope |
HOW IS PITYRIASIS VERSICOLOR TREATED?Treatment with creams and lotions for the skinIf the area to be treated is not very extensive, it can be treated with an antifungal cream such as ketoconazole cream or ciclopirox cream. Apply this to the affected area once a day for two weeks.
In addition, treat the scalp twice a week with ketoconazole scalp gel, as the scalp is an ideal habitat for the yeasts. From the scalp, they can spread to the rest of the body. Those who regularly suffer from recurring pityriasis versicolor should continue treating the scalp regularly (for example, once a week) with ketoconazole gel. The gel should be applied to the scalp in the shower after washing hair, left on for five minutes, and rinsed. See further under dandruff .
For larger areas, an anti-dandruff shampoo such as Selsun (selenium disulfide) or Nizoral scalp gel (ketoconazole gel) can also be applied to the entire body.Selsun:Dilute the Selsun anti-dandruff shampoo with a small amount of water and spread it over your entire body with a washcloth. Do not apply it to your face, genitals, or damaged skin (wounds); use it in your hair. Let the shampoo soak in for 10 minutes and then rinse thoroughly. Do this once a day for 7 consecutive days.
The old instructions for using Selsun for pityriasis versicolor were: apply the undiluted shampoo to your body, put on an old T-shirt or pajamas over it, and leave it on overnight. Rinse the next morning. This only needs to be done once, which is much more practical. However, because Selsun is also a soap, it is sticky and too irritating for some patients, hence the somewhat milder advice from the supplier. Those who can tolerate it may also use the undiluted overnight method.Ketoconazole head gel or shampoo:Ketoconazole shampoo can be used in the same way as Selsun: wash your hair (with an anti-dandruff shampoo if desired) and then leave the ketoconazole head gel or shampoo on for 5 minutes. Apply the ketoconazole shampoo to your entire body and leave it on for 5 minutes. Then rinse. Repeat this every day for 5 days.Treatment with tablets:In very extensive pityriasis versicolor, the yeast infection can also be treated by taking antifungal tablets. This kills the yeast from within, reaching all areas of the body.
The infection can still return afterward, because the yeast is ubiquitous in our environment, making re-infection easy. Therefore, it is also useful to maintain treatment with a ketoconazole shampoo.
Examples of antifungal tablets include:
Itraconazole 100 mg capsules.
Take two 100 mg capsules at once daily for one week.
Fluconazole 150 or 300 mg tablets.
Take one 150 or 300 mg tablet once a week for two to four weeks.WHAT CAN YOU STILL DO YOURSELF?You can try to avoid circumstances that aggravate the condition (warm temperatures, humid conditions, excessive sweating). Other tips include: always allowing your skin to dry thoroughly after showering, not walking around in sweaty clothing for extended periods, and sleeping in a cool bedroom. However, the condition can always recur, and some people are more susceptible than others. If the condition has recurred several times, ketoconazole scalp gel can be used preventatively during the summer months.WHAT ARE THE OUTLOOK?After pityriasis versicolor has healed, the light spots can persist for a long time. This is because the yeast cells secrete a substance that has a (sometimes long-lasting) inhibitory effect on pigment formation. This can sometimes cause confusion: the yeast has been effectively combated and killed, but the skin condition remains just as visible and doesn't seem to have disappeared. Generally, the pale spots will disappear spontaneously over the summer or after about six months. If the white spots remain visible, a tanning bed session can sometimes be effective in restoring the pigment to the white areas. This can be a regular tanning bed session at a tanning salon, and you can also achieve this effect with natural sunlight.
Unfortunately, pityriasis versicolor is a condition that can recur frequently in people who are susceptible to it. |
