Pityriasis versicolor

Pityriasis versicolor
MUDr. et MUDr. Pavel Konrád
Dermatology Clinic, Černošice / Lasermed

Pityriasis versicolor 

This article describes pityriasis versicolor, a very common type of skin surface mycosis in younger people. The article clarifies its name, its etiopathogenesis, the most effective therapy currently available and the necessary preventive measures.

Key words – pityriasis versicolor, Malassezia furfur, dark ichthammol, combination therapy, sulphate-free syndets.

Origin of the Disease’s Name

The disease’s compound name, pityriasis versicolor aptly describes its clinical picture. Pityron means bran in Greek, comparing the scales peeling off the skin. The Latin word, versicolor means multi-colored, it is made up of the words: vertere – turn and color – color. The foci of the disease are a different color in the summer and a different color in the winter. The affected foci are lighter in the summer compared to the unaffected skin. The surrounding skin is colored with UV ray induced pigment. On the contrary, in the winter, when the skin is pale, the affected foci appear more pronounced than the surrounding healthy skin. The reason for hypo-pigmentation of the affected foci is very interesting. The inducing yeast of the Malassezia genus produces azelaic acid as its metabolite, which inhibits the tyrosinase  enzyme, thereby decreasing the production of melanin. In therapy, this ability of azelaic acid (for example, Skinoren cream) is used to treat melasmas or post-inflammatory hyper-pigmentation, like for example, post burns.

History

Prof. Carl Ferdinand Eichstedt (* 17 September 1816 in Greifswald; † 31 December 1892 in Greifswald) was a German gynecologist and dermatologist (Fig.1). He identified the yeast agent, Pityriasis versicolor and was the first to name this disease (1). In dermatology, he emphasized the importance of the microscope in detecting diseases. His publication, Pilzbildung in der Pityriasis versicolor came out in 1846. Thanks to this publication, he became one of the immortal authors of dermatology-related literature.

Definition

It is a very common mycosis that appears on the top layer of the skin in younger adults. It is caused by lipophilic Malassezia genus yeasts, manifesting in pityriasis form with peeling off macula that is initially located on the shoulders and then moves to the torso.

The Origin and Triggering Factors

The disease is caused by Malassezia genus yeasts (formerly known as Pityrosporon), most often Malassezia globosa (50-60%), Malassezia sympodialis (3-59%), Malassezia furfur and Malasezia  slooffiae (1-10%), which under normal circumstances are common skin saprophytes (2).

The infection is caused by the transition of Malassezia from the yeast phase to the micellar phase (2). Various internal and external factors aid this transformation. The most important external factors are heat and humidity. Therefore, the symptoms typically occur in tropical weather. The affected parts of the skin tend to be those that are covered by clothing, especially if we’re talking about frequently wearing multiple layers made of artificial material or a combination of material. Work in hot conditions may also be a predisposing factor.

The internal factors supporting the development of skin manifestations include excessive sweating – hyper-hyperhidrosis, an increased formation of sebum – seborrhea (most often these are hereditary influences), immuno-suppression, treatment using complete or local corticoids and the Cushing Syndrome (3).

Clinical Picture and Differential Diagnosis

The basic efflorescence of the disease is macules (Fig. 2), with discreetly peeling edges, which usually do not itch. However, some patients rarely experience excruciating pruritus (the author’s note). The foci tend to be multiple, clearly defined, from whitish to red, red-brown to brown. There may be a combination of colors in these patients. It typically occurs on the neck and shoulders (Fig. 3), on the back (Fig. 4,5,6), above the sternum, between the breasts in women (Fig. 7), under the breasts and in the elbow bends. Slightly noticeable pityriasis-form desquamation after scratching (4). This is what reliably sets this disease apart from vitiligo. Patients experience fine “dry” dandruff in capillitia, similar to cigarette ash, unlike larger “greasy” dandruff in seborrheic dermatitidis.

Diagnosis

The clinical picture is usually characteristic. Typical grape-like clusters of budding spores are visible under the microscope. When examined under Wood’s light, yellowish fluoresce is manifested (2,4). Malassezia practically cannot be cultivated, so mycology swabs are irrelevant (5).

Therapy

Patients with pityriasis versicolor tend to have more sebaceous glands and thus increased sebum secretion (6). Moreover, the composition of the sebum is one, where yeasts metabolize well, which gives tendency for this disease to thrive for life! There is a tendency for early exacerbation even following good treatment.

Therapy of this disease is oftentimes underestimated and insufficient. Moreover, the education that every patient needs in order to prevent the exacerbation of the disease is often forgotten. This is practically inevitable without follow-up measures and necessary changes to your hygiene routine.

Usually, patients go to the out-clinic with already long-lasting symptoms, with foci affecting a large part of the body. In these cases, the only effective therapy is complete combination therapy and local antimycotics combined with ichtamol shampoos.

Antimycotics directly eliminate the yeasts. Ichtamol has several effects, it stops itching, it has anti-inflammatory effects, keratoplastic effects, it is slightly antiseptic and anti-seborrheic (6). Its anti-seborrheic effect prevents the overgrowth of yeast by reducing the amount of sebum, which yeast is metabolically dependent on.

Take 200mg of itrakonazol, once a day for 7 consecutive days (for example, Sporanox cps., Prokanazol cps., Conisor cps.). Use antimycotic shampoos (for example, Micetal shampoo, Nizoral shampoo) and shampoo with dark ichtamol (for example, Ichtyol shampoo) (6) in the first week. Alternate using the shampoo every other day. It is essential to apply the shampoos on the affected skin and also rub them into the scalp at the same time! Let sit for 5min and then rinse with water. From the second week, switch to using the shampoos twice a week – for example, an anti-mycotic shampoo on Tuesday and an ichtamol shampoo on Friday. Use the shampoo until you run out, however, for at least 3 weeks.

The depigmentation foci do not disappear immediately after completing the therapy. The color changes disappear following subsequent pigmentation of the skin using UV rays.

Prevention

Preventive measures set in immediately after the therapy. It is recommended to use an ichtamol shampoo long-term, basically forever, at least once per week. Ichtamol has antiseptic effects, which last for about one week when applied locally. More sebum begins re-producing after this period and excessive growth, otherwise known as saprophytic yeasts recur, resulting in an exacerbation of the disease. This biological cycle is the reason why ichtamol shampoo has to be used long-term.

The second crucial element of prevention is using sulphate-free syndettes. Sulphates, mainly sodium lauryl sulphate (SLE) and sodium laureth sulphate (SLES) destroy the skin’s biofilm and help yeast grow on the skin. It is necessary to completely stop using these products and completely replace them with sulphate-free syndettes, which can be used to wash the skin and hair (for example, Cutosan Cleansing Gel). This preventive measure also applies for life!

It is recommended that patients wear loose-fitting, breathable clothes made of 100% cotton.

Resumé

Pityriasis versicolor is a disease that mainly affects patients with a genetic predisposition, inclined to increased sebum production and characteristic sebum composition. An exacerbation of the disease is almost certain if preventive measures are not followed!

Literature:

1. Braun-Falco O, Plewig G, Wolf H. Dermatology and Venerology. Osveta, Ltd., Martin 2001,257 p.
2. Benáková N. et al. Modern Pharmacotherapy in Dermatology, Prague: Maxdorf : 2020, 30 p.
3. Baker H. Clinical dermatology, fourth edition, London: Bailliere Tindall 1989, 70-71 p.
4. Štork J, et al. Dermato-venerology. Prague Galén, 2008,78-79 p.
5. Danda V. et al. Selected chapters from dermato-venerology, Hradec Králové: Military Medical Academy 1979, 81 p.
6. Fadrhoncová A Pharmacotherapy of Skin Diseases, Prague: Grada 1999, 364-365 p.