Does pityriasis versicolor look like a flower? Who is most likely to get it?

Author: Wang Aiping, Chief Physician, Peking University First Hospital

Deputy Director of the Dermatomycology Group of the Chinese Society of Dermatology and Venereology

Reviewer: Chen Yong, Chief Physician, Beijing Chaoyang Hospital, Capital Medical University

Pityriasis versicolor, also known as tinea versicolor and tinea versicolor, is a common skin disease, the main pathogen of which is Malassezia.

Malassezia is a normal resident bacterium on the surface of human skin. Everyone has it. However, under certain conditions, Malassezia will multiply abnormally and cause disease, causing pityriasis versicolor.

Brown, white, red, or even yellow spots appear on the skin, and there are some fine, bran-like scales on the various spots, so it is called pityriasis versicolor.

Figure 1 Original copyright image, no permission to reprint

Malassezia often resides in areas where sebum secretions occur, such as the head, face, neck, trunk, armpits, and groin, so pityriasis versicolor often occurs in areas where sebum secretions occur.

Pityriasis versicolor usually occurs in the summer when the climate is relatively hot. It is not easy to get pityriasis versicolor in cold places. In general, climate is a very important factor, and it is more likely to occur in warm and humid areas.

Most cases of pityriasis versicolor have no symptoms, and some may experience slight itching. Because there is no discomfort, many patients will not go to the hospital for treatment.

1. What factors may trigger pityriasis versicolor?

Pityriasis versicolor occurs more often in people with normal immune function, with susceptibility factors, and some are familial.

For example, if one has poor hygiene habits and does not like to take a bath, it will lead to excessive secretion of sebum on the body surface in hot seasons, causing abnormal reproduction of Malassezia.

There are other factors that are relatively rare, such as diabetics or people who sweat a lot, which can easily lead to pityriasis versicolor. Some people like to wear tight clothes, which can also easily lead to pityriasis versicolor.

2. Which groups of people are most susceptible to pityriasis versicolor?

There are two peak periods of pityriasis versicolor: one is the neonatal period, and the other is the young and middle-aged period.

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When a newborn is born, his body carries some hormones from his mother, especially androgens, which causes more sebum secretion in the newborn. Therefore, pityriasis versicolor is particularly prone to occur on the head, face and neck. As the age increases, it will generally improve after one year old.

After puberty, usually after the age of 12, the secretion of sex hormones leads to the development of sebaceous glands. The increase in skin oil will cause pityriasis versicolor, so pityriasis versicolor is more common in young and middle-aged people.

As people age, the sebaceous glands gradually degenerate, and fewer elderly people suffer from pityriasis versicolor.

3. How to diagnose pityriasis versicolor?

The clinical manifestations of pityriasis versicolor are very typical, especially the brown spots with clear borders and different sizes, which occur on the trunk, armpits, or groin. They have no symptoms and are easy to diagnose. However, they are sometimes easily confused with café au lait spots and some pigmented nevi, and need to be differentiated from them.

If conditions permit, a fungal examination can be done. If it is pityriasis versicolor, you can often see a lot of Malassezia hyphae under the microscope. The hyphae are relatively short, thick, and S-shaped. Some patients will also see spores, so in medicine it is described as being able to see both "bananas" and "grapes." This is a very typical pityriasis versicolor.

Because Malassezia generally parasitizes near sebaceous glands and is lipophilic, pityriasis versicolor generally does not require fungal culture and can be diagnosed directly by microscopic examination.

Theoretically, once you get pityriasis versicolor, it is difficult to heal on your own. Generally, intervention treatment or temporary killing of Malassezia is required to achieve the goal of cure.

4. How to treat pityriasis versicolor?

Pityriasis versicolor is usually treated with topical medications. Malassezia is a fungus, so antifungal topical medications should be used. If pityriasis versicolor is particularly stubborn and widespread, and the patient wants to get better as soon as possible, oral antifungal medications can be considered.

For topical medication, pityriasis versicolor has a wide range of applications and is suitable for lotion treatment. The most commonly used lotions are 2% ketoconazole lotion and selenium disulfide lotion, which can be used to clean the skin like a bath. There are also various topical antifungal sprays, solutions, and creams that can be used.

The general treatment time for pityriasis versicolor is 2 to 4 weeks. For most patients, the level of Malassezia can be reduced below the threshold of disease occurrence after about 2 weeks of treatment.

5. How do patients with pityriasis versicolor take care of their skin on a daily basis?

Patients with pityriasis versicolor should take frequent baths and pay attention to personal hygiene in the hot summer. If you sweat a lot, you must pay attention to cleaning and dry all the wrinkles after cleaning. This is very important.

In summer, you should wear clothes that are more breathable, wear more cotton clothes, and avoid tight and poorly absorbent clothes.

In addition, you should control your weight and try not to use immunosuppressive drugs, otherwise it will aggravate the reproduction of Malassezia.

Patients who are prone to pityriasis versicolor can use ketoconazole lotion to clean their skin from time to time from March to October each year to kill some of the excess Malassezia. Preventive medication can prevent the occurrence or recurrence of pityriasis versicolor.