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63 Prurigo, Prurigo Simplex
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Figs. 63.6 and 63.7 Prurigo on the forehead
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Pityriasis Versicolor, Tinea Versicolor
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64
For others, it’s a skin disease that only occurs in the summer, but for me, it drives me crazy to live with it not only
in the summer but also in the winter (Fig.64.1).
A 31-year-old male, D, has a job that requires him to sweat
even on cold days, so for others, it is a pityriasis versicolor
that only occurs in the summer, but for him, it occurs not only
in the summer but also in the winter. It’s hard to make time to
go to the hospital, so he doesn’t get treatment, so it’s like living with this skin disease. When told, “Take a shower often
when you sweat, and get proper treatment!” he replied, “I
wish I could. But my circumstances don’t allow it”.
Pityriasis versicolor is a supercial fungal infection
caused by the lipophilic yeast Malassezia, which belongs to
the normal ora of the skin. Research on the causative fungus of pityriasis versicolor was rst conducted by Eichstedt
and Sluyter, who named this disease “pityriasis versicolor”
in the mid-1800s, and in 1889, Baillon named this fungus
“Malassezia furfur,” which is still in use today. Recently,
Fig. 64.1 Pityriasis versicolor observed on the body
Malassezia yeasts were classied into 7 species including M.
furfur, M. pachydermatis, M. sympodialis, M. globosa, M.
obtusa, M. restricta, and M. sloofae by using morphology,
ultrastructure, and physiology based on molecular biology.
Also, 4 species, M. dermatis, M. japonica, M. nana, and M.
yamatoensis, classied by analyzing genotype, were added,
making a total of 11 species. Malassezia yeast is a lipophilic
species that is particularly distributed on the scalp, upper
body, and wrinkled areas. It is a normal ora that exists on
the skin of healthy people, but under appropriate conditions,
it becomes pathogenic. It is a skin disease in which some
Malassezia species that existed in a yeast form change into a
mycelial form by a mechanism that is not yet known, showing pathogenicity and forming hyperpigmented or hypopigmented scaly lesions on the skin. High temperature and
humidity, excessive sweat secretion, seborrheic skin, genetic
factors, excessive topical application of lipid components,
and immune suppression are known risk factors for the
occurrence of tinea versicolor. Therefore, it mainly occurs in
the hot and humid summer when a lot of sweat is produced,
and the prevalence is higher in tropical regions than in temperate regions (Figs.64.2 and 64.3).
It usually occurs on the chest, back, armpits, and neck of
active 20–40years old adults, where sebaceous glands are
densely distributed. Various sizes of light loess color, yellowbrown, and red-brown scales appear, and sometimes they
merge to form large patches. In adults, it is rare to occur on
the face and scalp. There are almost no conscious symptoms,
but mild itching can be complained of, and it shows a chronic
course, worsening in the summer and improving in the fall
and winter. The color change in tinea versicolor is due to
changes in the formation of melanosomes and the degree of
distribution within keratinocytes. In hypopigmented lesions,
the size of melanosomes is smaller than in normal skin, and
it can be observed that the distribution into keratinocytes is
not well distributed. In hyperpigmented lesions, the size of
melanosomes increases and the distribution pattern within
the epidermis changes. It is common for hypopigmented
© The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024
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Fig. 64.2 Typical form of pityriasis versicolor lesion
64 Pityriasis Versicolor, Tinea Versicolor
lesions to appear in areas exposed to sunlight, especially on
the face, so it can be difcult to distinguish from vitiligo, so
caution is needed in children where lesions often occur in
these areas. Tinea versicolor lesions very rarely show atrophic changes, and pityriasis versicolor atrophicans mainly
appears as asymptomatic atrophic patches on the trunk.
Histologically, hyphae and spores are observed in the epidermis, and a decrease in elastic bers in the dermis is observed.
The pathogenetic mechanism of pityriasis versicolor atrophicans is associated with long-term topical steroid use and is
claimed to be due to delayed hypersensitivity (Figs. 64.4,
64.5, 64.6, 64.7, 64.8, 64.9 and 64.10).
Tinea versicolor is known to occur rarely in children, but
in a Korean study, out of 669 patients with tinea versicolor,
32 were children under 14years old, accounting for 4.7%.
Since the causative yeast of tinea versicolor is lipophilic, the
incidence increases around puberty when the function of the
sebaceous glands becomes active, and the age group with the
Fig. 64.3 Tinea versicolor on the chest
Figs. 64.5 and 64.6 Tinea versicolor on the face (hypopigmented lesions)
Fig. 64.4 Pityriasis versicolor atrophicans
64 Pityriasis Versicolor, Tinea Versicolor
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Figs. 64.7 and 64.8 Hypopigmented lesions on the face and neck
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Figs. 64.9 and 64.10 Hypopigmented lesions on the neck
highest incidence is 10–14years old, accounting for 43% of
pediatric patients. Next, the incidence was high in the group
under 1year old, accounting for 28%, and the known triggers
for infantile tinea versicolor include persistence of maternal
androgen hormones, contact with infected parents, length of
stay in the neonatal intensive care unit for premature babies,
seborrheic dermatitis, and high humidity. Pediatric tinea versicolor occurred in 56% of cases on the face, a site where it
is rare in adults, and was not common on the chest and back,
which are common sites in adults. In particular, infantile
tinea versicolor often occurs on the face, especially the forehead, and rarely invades the scalp. Hypopigmented lesions
accounted for 96.9% and hyperpigmented lesions for 40.6%,
which is a signicant difference from the report that the area
of hyperpigmentation in adults is about 3 times more than
the area of hypopigmentation. The cause of hypopigmentation is not certain, but in the past, it was said to be because
the fungus lters sunlight and prevents normal tanning.
However, after that, it has been known that azelaic acid, a
dicarboxylic acid, which is a metabolite of Malassezia
yeasts, acts as a competitive inhibitor of tyrosinase in the
melanin production process, and recently, it has been
reported to be due to toxic lipid peroxides formed by the
lipid peroxidation of the causative yeasts on unsaturated fats
on the skin surface (Figs.64.11, 64.12, 64.13, 64.14, 64.15,
64.16, 64.17, 64.18, 64.19, 64.20, 64.21, 64.22, 64.23,
64.24–64.26, and 64.27–64.29).
When observing a suspected tinea versicolor lesion with a
Wood’s lamp for diagnosis, a characteristic yellow-brown or
golden-yellow uorescence appears. However, even if a
patient has tinea versicolor lesions, they may not emit uorescence in a Wood’s lamp examination if the patient has
sweated heavily or just after bathing. If a thin scale is raised
by scraping the lesion with a scalpel, it is likely to be tinea
versicolor. In cases where it is difcult to differentiate clinically, after collecting scales and applying a 1:1 mixture of
KOH solution and Parker ink, examination under a
microscope reveals a “spaghetti and meatball shape” with a
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Fig. 64.11 Tinea versicolor on the neck
Fig. 64.12 Tinea versicolor on the back
Fig. 64.13 Tinea versicolor on the back
64 Pityriasis Versicolor, Tinea Versicolor
mixture of short hyphae and round spores. Culture tests are
conducted at 34 °C with high humidity for 2 weeks on
glucose- peptone agar appropriately supplemented with fat.
Skin biopsy can be helpful in diagnosing tinea versicolor.
PAS staining or methenamine silver staining allows observation of short hyphae and budding round yeasts within the
stratum corneum and ndings of melanosomes of various
sizes and pigment incontinence. Recently, various molecular
biological techniques that are faster and more accurate than
existing test methods have been introduced and are being
applied clinically. Tinea versicolor requires differential diagnosis from pityriasis alba, pityriasis rosea, seborrheic dermatitis, conuent and reticulated papillomatosis, progressive
macular hypomelanosis, and syphilis (Fig.64.30).
Various drugs are used in the treatment of tinea versicolor,
and since the recurrence rate is known to be quite high in the
case of topical agents, it is effective to take oral antifungal
agents concurrently, which has the effect of high antifungal
effect and shortening the treatment period. Topical agents
such as clotrimazole, ketoconazole, pyrithione zinc, selenium sulde, and sodium thiosulfate are used, and it is effective to apply them in the evening after bathing, and they
should be applied to most of the upper body much wider than
the lesion area. The scales will disappear within a few days
after treatment, but the application should be continued for
several weeks. Pigment changes begin to show effect gradually, so they normalize after several months. In addition to
clotrimazole, 2% ketoconazole, and other topical antifungal
creams, 2% ketoconazole shampoo is used for the treatment
and recurrence prevention of dandruff, seborrheic dermatitis,
and tinea versicolor caused by yeast, and it is applied to the
tinea versicolor infection area and applied like a regular
shampoo for 3–5 min. Then rinse off, for tinea versicolor
treatment, use once a day, up to 5days, and for recurrence
prevention, use once a day, up to 3days as a single therapy
before exposure to sunlight. Shampoos containing pyrithione
zinc are effective against lipophilic yeasts, and 2.5% selenium sulde and 25% sodium thiosulfate products are not
currently produced and distributed in Korea. When choosing
an oral medication, because tinea versicolor is chronic and
relapses are common, it is most important to select a medication that has high antifungal activity, is easy to take, and has
few side effects to increase patient compliance and treatment
effectiveness. Oral antifungal agents such as itraconazole
and uconazole are commonly used. It is known that a treatment rate of 90–100% can be achieved by administering
200–400mg of itraconazole daily for 3–7days. Fluconazole
is administered at 50mg once a day for 2–4weeks or 150mg
64 Pityriasis Versicolor, Tinea Versicolor
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Figs. 64.14 and 64.15 Tinea versicolor on the back
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Figs. 64.16 and 64.17 Tinea versicolor on the chest
Figs. 64.18 and 64.19 Tinea versicolor on the armpit and upper arm
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Figs. 64.20 and 64.21 Tinea versicolor on the arm
64 Pityriasis Versicolor, Tinea Versicolor
Figs. 64.22 and 64.23 Tinea versicolor on the groin
64 Pityriasis Versicolor, Tinea Versicolor
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Figs. 64.24–64.26 Tinea versicolor showing hypopigmented lesions
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64 Pityriasis Versicolor, Tinea Versicolor
Figs. 64.27–64.29 Wood’s lamp examination of tinea versicolor lesions
Fig. 64.30 If the treatment of tinea versicolor is delayed, substances
produced from the causative yeasts can inhibit the production of melanin, leading to a decrease or loss of skin pigment. It is good to inform in
advance that the depigmented spots can persist for a long time even
after treatment for tinea versicolor
once a week for 2–4 weeks. Terbinane is reported to be
ineffective when administered orally because it is difcult
for the treatment dose to reach the stratum corneum, but a
topical 1% terbinane solution is useful. Patients should be
informed in advance that hypopigmentation can persist for a
long time after treatment. They should be advised not to
apply oil components when bathing and to shower quickly
after sweating. Malassezia yeast is a normal skin ora, so it
is difcult to completely eliminate it with treatment, and it is
also difcult to completely remove the inducing factors, so it
should be explained that about 60% recur 1year after the end
of treatment and about 80% recur 2years later. I told Mr. D
that even if it is difcult to nd time, he should rst receive a
complete treatment for a sufcient period of time and then
manage it well so that it does not recur.
Tinea Faciei: Tinea Faciale
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65
Suddenly, my child developed a ring-shaped skin disease
on her face (Fig.65.1).
The mother of an 11-year-old girl, K, said, “My child’s
face seemed to have been bitten by something a while ago,
and it gradually grew into a ring-shaped skin disease!” So, I
thought of several skin diseases that occur in coin or ring
shapes on the face and put the loupe on my forehead.
Tinea faciei, also known as tinea faciale, accounts for
about 5% of dermatophytosis patients and occurs on the
faces of men and women (excluding areas where men have
beards). Its clinical manifestations vary widely, so it is
important to distinguish it from other diseases that occur on
the face. In the past, it was included in tinea corporis, but
recently it has been treated as an independent category of
disease because the anatomical structure of the face is different from other parts, and it shows characteristic lesion patterns. The biggest reason for separating tinea faciale from
tinea corporis is that the misdiagnosis rate of tinea faciale is
higher than that of tinea corporis. The lesions show a characteristic ring shape like tinea corporis, but the shape of the
lesions and clinical symptoms vary widely, and sometimes
the shape of original lesion may be distorted due to abuse of
steroids. Therefore, it makes easy to misdiagnose when ringshaped lesions do not appear, the boundaries are unclear, and
there are small amounts of scales and crusts. Since the face is
always exposed to various external stimuli, such as frequent
washing, the lesions of tinea faciale are more prone to deformation than other dermatophytosis, so the boundaries
become unclear and fungal (KOH) tests are often negative.
In addition, there are many cases where tinea incognito is
induced and misdiagnosed due to the abuse of various topical
preparations including steroids. If tinea faciale is suspected,
a sufcient amount of scales is collected from slightly inside
the lesion border and a KOH test and fungal culture test are
performed to conrm the diagnosis (Figs.65.2, 65.3, 65.4,
65.5, 65.6 and 65.7).
Tinea faciale is effective with topical application of anti-
fungal cream. In severe cases or when there is no response to
topical treatment, oral antifungal agents are administered for
2–4weeks. There are reports that 85% of adult patients with
tinea faciale have nail involvement by the same strain as the
Fig. 65.1 Tinea faciale observed on the face Fig. 65.2 Tinea faciei
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