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Characteristics of Riehl melanosis in an ethnic Asian population: A comparative study according to age, sex, and hair dye use

  • Harvard Medical School, Cutaneous Biology Research center


Riehl melanosis, characterized by diffuse brown to grey hyperpigmentation of the face and neck, affects middle‐aged women with dark skin phototypes. Riehl melanosis prevalence has increased in Korea, and a relationship with henna hair dye has been suspected. In this study, we aimed to evaluate clinical features and patch test results of Riehl melanosis patients and analyse them according to age, sex, and hair dye use. We identified patients showing clinical and histopathological manifestations consistent with Riehl melanosis between January 2009 and December 2019 in our medical centre. Of 154 patients, 76.5% had positive patch‐test results, and the most common sensitizing agents were nickel, cobalt, and benzyl salicylate. Patients ≥50 years old were more likely to have spotty hyperpigmentation and less likely to have diffuse patterns, while lesions in the younger‐aged group were more commonly accompanied by erythema. Preceding erythema was found more often in female patients. Hair dye usage was more likely to be associated with aggravation of symptoms in females. Patients who developed Riehl melanosis after hair‐dye use more frequently had lesions on the forehead and were diagnosed an average of 14.1 months earlier as compared with other patients. Short disease duration, aggravation by hair dye (except henna), laser therapy, and longer follow‐up periods were related to good treatment responses. Detailed history taking regarding disease duration and aggravating factors as well as the length of the period of laser therapy can be important for the management of Riehl melanosis patients.
Received: 4 April 2022
Accepted: 23 May 2022
DOI: 10.1002/jvc2.44
Characteristics of Riehl melanosis in an ethnic Asian
population: A comparative study according to age, sex,
and hair dye use
Myoung Eun Choi
|Youngkyoung Lim
|Woo Jin Lee
Chong Hyun Won
|Mi Woo Lee
|Sung Eun Chang
Department of Dermatology, Asan
Medical Center, University of Ulsan
College of Medicine, Seoul, Republic of
Deparment of Dermatology, Seoul
National University, Seoul, Republic of
Sung Eun Chang, Department of
Dermatology, Asan Medical Center,
University of Ulsan College of Medicine,
88 Olympicro 43 gil, Songpagu,
Seoul 05505, Republic of Korea.
Funding information
Background: Riehl melanosis, characterized by diffuse brown to grey
hyperpigmentation of the face and neck, affects middleaged women with
dark skin phototypes. Riehl melanosis prevalence has increased in Korea, and
a relationship with henna hair dye has been suspected. In this study, we aimed
to evaluate clinical features and patch test results of Riehl melanosis patients
and analyse them according to age, sex, and hair dye use.
Methods: We identified patients showing clinical and histopathological
manifestations consistent with Riehl melanosis between January 2009 and
December 2019 in our medical centre.
Results: Of 154 patients, 76.5% had positive patchtest results, and the most
common sensitizing agents were nickel, cobalt, and benzyl salicylate. Patients
50 years old were more likely to have spotty hyperpigmentation and less
likely to have diffuse patterns, while lesions in the youngeraged group were
more commonly accompanied by erythema. Preceding erythema was found
more often in female patients. Hair dye usage was more likely to be associated
with aggravation of symptoms in females. Patients who developed Riehl
melanosis after hairdye use more frequently had lesions on the forehead and
were diagnosed an average of 14.1 months earlier as compared with other
patients. Short disease duration, aggravation by hair dye (except henna), laser
therapy, and longer followup periods were related to good treatment
Conclusions: Detailed history taking regarding disease duration and
aggravating factors as well as the length of the period of laser therapy can
be important for the management of Riehl melanosis patients.
contact dermatitis, inflammatory disorders, pigmentary disorders
JEADV Clin Pract. 2022;110.
This is an open access article under the terms of the Creative Commons AttributionNonCommercialNoDerivs License, which permits use and distribution in any
medium, provided the original work is properly cited, the use is noncommercial and no modifications or adaptations are made.
© 2022 The Authors. JEADV Clinical Practice published by John Wiley & Sons Ltd on behalf of European Academy of Dermatology and Venereology.
Myoung Eun Choi and Youngkyoung Lim contributed equally to this study.
Riehl melanosis, also known as pigmented contact
dermatitis, was first described by Riehl in 1917.
It is
characterized by brown to grey discolouration of the face
and neck affecting Asian women with dark skin
Strikingly, the prevalence of Riehl melano-
sis shows an upward trend in Korea, and the possibility
of a relationship with henna hair dye has been
However, the increase in the use of
irritating cosmetics, exposure to hot baths, scrubbing
with flannel, as well as laser procedures also parallels the
increase in Riehl melanosis patients.
Korean patients with Riehl melanosis had clinical
differences from the original description of Riehl
melanosis in that in these patients it tended to present
initially with illdefined erythematous patches before the
development of brown to grey pigmentation. Moreover,
the majority of Korean Riehl melanosis patients had
concurrent impairment of skin barrier function accom-
panied by various degrees of symptoms such as itching,
dryness, burning, and hot sensations with the initiation
and aggravation of Riehl melanosis lesions. Currently, it
is not uncommon to see Riehl melanosis patients
younger than 40 and even male Riehl melanosis patients
despite the fact that the disorder mostly affects middleto
olderaged women. However, there has been limited
clinical analysis according to age and sex because of the
rarity of disease in these groups (<40 years old and male
patients) in the past.
The treatment of Riehl melanosis includes topical
blanching agents, topical steroids, topical calcineurin
inhibitors, oral steroids, and laser therapy. However,
the results of treatment have had variable degrees of
success, and some patients have complained of
aggravation during the course of treatment.
the factors that affect the treatment response of Riehl
melanosis have not been studied, it is difficult to
predict prognosis.
In this study, we evaluated clinical features and
patchtest results of Riehl melanosis patients and
analysed them according to age, sex, and hair dye use.
In addition, we investigated factors associated with
treatment response.
We identified a total of 154 patients with Riehl melanosis
evaluated in the Dermatology Department between
January 2009 and December 2019. This study was
approved by the Institutional Review Board (IRB) (IRB
approval no. 20190920). The medical records of these
patients were reviewed to gather clinical data, patchtest
results, and followup data. We included the patients
only if their skin biopsy results and clinical manifesta-
tions supported the diagnosis of Riehl melanosis. We
excluded patients who had other possible causes of
hyperpigmentation such as Addison's disease, hyper-
thyroidism, and hemochromatosis. Patients with hyper-
pigmentation in sites other than the face and neck were
also excluded.
Variables of interest
The clinical features of the primary lesions, such as age at
diagnosis, sex, anatomical location of the lesion, mor-
phology, multiplicity, clinical course, symptoms, time to
diagnosis, and causative agents were identified through
medical records and clinical photographs. Histopatho-
logical slides of all patients were reviewed by two
Patch test
Standard patchtest kits (Korean Standard Series [KOR
1000] and Cosmetic Series [C1000]), as well as several
suspected products brought in by patients, were used for
patch testing in 34 patients. The patch tests were applied
on the back for 2 days. The interpretation of the results
was based on the International Contact Dermatitis
Research Group scoring scale (ICDRG) guideline at 48
and 96 h after application. Delayed reactions were
recorded as needed.
Clinical outcome measures
Clinical outcomes were evaluated based on clinical
photographs obtained at baseline and at the last time
medical photographs were taken. Two dermatologists
compared the initial photographs with the final follow
up photographs in a blind manner and assessed the
treatment response according to the percentage pigment
clearing as follows: none to fair (0%25%, score = 0),
moderate (26%50%, score = 1), good (51%75%, score =
2), or excellent (76%100%, score = 3). Global assessment
scale (GAS) scores (0 [no pigmentation]to4[severe
pigmentation]) were used to measure pigmentation
severity. Treatment response was defined as pigment
clearing 26% (a grade of moderate to excellent) in
evaluating prognostic factors.
Statistical analysis
All data were statistically analysed using SPSS version
18.0 (SPSS Inc.). pValues < 0.05 were considered to be
statistically significant. Comparisons between subgroups
of patients according to age and sex were performed
using a χ
test or Fisher exact test for categorical variables
and a ttest for continuous variables. Logistic regression
analyses were performed in sequence to determine the
independent prognostic factors associated with treatment
Clinical manifestations
The clinical features of the patients are presented in
Table 1. The mean patient age was 56 years (range: 1886
years). There were 15 male patients and 139 females.
Mean time to diagnosis was 24.1 months, ranging from 1
to 180 months. Of the patients, 40.3% had preceding
erythema. More than half of patients (54.5%) had itching
before initiation of hyperpigmentation. Facial flushing
was noted in 20.8% of patients. Photosensitivity and
dryness were symptoms seen in 9.7% and 11.7% of Riehl
melanosis patients, respectively. A variety of factors were
reported to be related to the aggravation of Riehl
melanosis, and more than one factor could be associated
with the aggravation. Henna hair dyes as well as other
hair dyes were most commonly reported by patients as
aggravating factors, followed by cosmetics, sunlight, heat,
friction, and laser procedures. Other factors included
hormonal treatment, herbal medications, and mental
stress. In classification by the Fitzpatrick skin type, 48
patients (31.2%) were Type III, 105 patients were (68.2%)
were Type IV, and 1 patient (0.6%) was Type V. The face
was involved in 89.6% of patients, and the neck was
involved in 72.7% of patients. Among those with facial
involvement, the lateral sides of both cheeks, followed by
the chin and forehead, were most commonly involved. A
wide range of clinical manifestations of hyperpigmenta-
tion, as well as mixed types of hyperpigmentation, was
noticed. Although diffuse hyperpigmentation over the
face and neck (71.4%) was the most commonly observed
pattern, spotty (37.0%) and reticulated (9.1%) hyperpig-
mentation were also found.
Patchtest results
Patch tests were performed on 34 patients and the results
are listed in Table 2. Twentysix cases showed positive
TABLE 1 Clinical features of Riehl melanosis
Clinical parameters Number of patients (%)
Number of patients 154
Male 15 (9.7%)
Female 139 (90.3%)
Mean age (range, years) 56.0 (1886)
Mean time to diagnosis (range, months) 24.1 (1180)
Preceding symptoms and signs
Erythema 62 (40.3%)
Itching 84 (54.5%)
Facial flushing 32 (20.8%)
Associated symptoms and signs
Photosensitivity 15 (9.7%)
Dryness 18 (11.7%)
Aggravating factors
Henna hair dye 34 (22.1%)
Hair dye other than henna 47 (30.5%)
Laser treatment 10 (6.5%)
Peeling 7 (4.5%)
Friction 14 (9.1%)
Cosmetics 22 (14.3%)
Exercise 7 (4.5%)
Sunlight 21 (13.6%)
Heat 16 (10.4%)
Others 24 (15.6%)
Fitzpatrick skin type
Mean (range) 3.7 (35)
III 48 (31.2%)
IV 105 (68.2%)
V 1 (0.6%)
Face 138 (89.6%)
Forehead 97 (63.0%)
Periocular area 79 (51.3%)
Cheek 115 (74.7%)
Nose 55 (35.7%)
Perioral area 83 (53.9%)
Chin 111 (72.1%)
Neck 112 (72.7%)
Clinical manifestation
Spotty 57 (37.0%)
Reticulated 14 (9.1%)
Diffuse 110 (71.4%)
results, while in 8 cases there was no reaction to the
agents in the patch test. Nickel sulphate hexahydrate was
the most common sensitizing agent (12 cases), followed
by cobalt chloride hexahydrate (5 cases) and benzyl
salicylate (5 cases). Fragrance mix, 4phenylendiamine,
and potassium dichromate were detected in three
patients each. Some patients had positive results with
products they brought in marked as as is,which
included henna hair dye, cosmetics such as sunblock,
spot cream, peeling agents (Meladopa®), and medications
such as Samlodipine nicotinate (Lodien®) tablet.
Histopathological features
The histopathological features of the patients are
presented in Table 3. In the epidermis, noticeable
acanthosis, atrophy, and spongiosis were observed in
11.0%, 9.7%, and 4.5%, respectively. Apoptotic bodies
were found in 54.5% of patients, and vacuolar degenera-
tion was found in 66.9% of patients. Basal hyperpigmen-
tation was observed in 14.3% of cases. In the dermis,
prominent perivascular inflammation and lichenoid
inflammation were observed in 63.0% and 22.7%,
respectively. Telangiectasia and capillary hyperplasia
were found in 28.5%, and dermal melanophages in the
upper dermis were observed in 94.2%. Severe solar
elastosis was found in 7.8% of patients.
Clinical analysis according to age
Clinical features were analysed according to age
(Table 4). There were 114 patients 50 or more years old
and 40 patients were less than 50 years of age. The use of
henna as well as other types of hair dye was a statistically
significant aggravating factor according to age (p= 0.026
for henna hair dye and p= 0.002 for other types of hair
dye). Moreover, older patients were more likely to show
spotty hyperpigmentation while less likely to manifest
diffuse hyperpigmentation (p= 0.003 and p= 0.009,
respectively). Accompanying erythema was found signif-
icantly more often in the youngeraged group (p= 0.016).
Other variables including sex, time to diagnosis, preced-
ing and associated symptoms, aggravating factors
other than hair dye, Fitzpatrick skin type, and location
of hyperpigmentation did not show any significant
TABLE 2 Frequency of allergen detection in patch tests in
Riehl melanosis
Results of
patch test Detected agents
Positive (n= 26) Fragrance mix 3
4Phenylendiamine 1.5% 3
Colophony 1
Cl+ Meisothiazolinone 1
Imidazolidinyl urea 1
pPhenylenediamine (PPD) 1
Benzyl salicylate 5
Formaldehyde 1
Nickel sulphate hexahydrate 12
Cobalt chloride hexahydrate 5
Potassium dichromate 3
Octyl gallate 2
Abitol 1
2Phenoxyethanol 1
Dimethylaminopropylamine 1
Tertbutylhydroquinone 1
glutaronitrile (MDBGN)
Henna 1
Negative (n=8)
Sunblock, Lodien tab, Meladopa peeling agent, spot cream.
TABLE 3 Histopathological features of Riehl melanosis
Histopathological features Patients (%)
Acanthosis 17 (11.0%)
Atrophy 15 (9.7%)
Spongiosis 7 (4.5%)
Apoptotic body 84 (54.5%)
Vacuolar degeneration 103 (66.9%)
Basal hyperpigmentation 22 (14.3%)
Perivascular inflammation 97 (63.0%)
Lichenoid infiltration 35 (22.7%)
Telangiectasia and capillary hyperplasia 44 (28.5%)
Dermal melanophages 145 (94.2%)
Prominent solar elastosis 12 (7.8%)
TABLE 4 Clinical characteristics of Riehl melanosis patients according to age and sex
Age 50
(n= 114)
Age < 50
(n= 40) pValue
(n= 15)
(n= 139) pValue
Sex 0.494 0.000*
Male 10 5 15 0
Female 104 35 0 139
Age of diagnosis (years) 61 43 0.000*56 58 0.571
Time to diagnosis (months) 22.7 28.1 0.306 28.0 23.7 0.598
Preceding symptoms and signs
Erythema 45 17 0.737 2 60 0.025*
Itching 63 21 0.763 5 79 0.082
Facial flushing 28 4 0.051 1 31 0.156
Associated symptoms and signs
Photosensitivity 13 2 0.240 2 13 0.621
Dryness 13 5 0.853 0 18 0.138
Aggravating factors
Henna hair dye 30 4 0.026*0 34 0.027*
Other hair dye 42 5 0.002*0 47 0.005*
Laser treatment 9 1 0.147 0 10 0.236
Peeling 5 2 0.873 1 6 0.678
Friction 11 2 0.363 0 13 0.216
Cosmetics 16 5 0.881 1 20 0.375
Exercise 4 3 0.280 2 5 0.087
Fitzpatrick skin type 0.694 0.268
Face 102 36 0.925 14 124 0.619
Forehead 73 25 0.862 11 87 0.411
Periocular area 60 19 0.543 8 71 0.890
Cheek 87 28 0.429 13 102 0.261
Nose 42 13 0.548 5 50 0.793
Perioral area 60 23 0.595 6 77 0.286
Chin 82 29 0.994 11 100 0.943
Neck 85 27 0.388 15 103 0.244
Clinical manifestations
Spotty 50 7 0.003*7 50 0.415
Reticulated 12 2 0.296 1 13 0.731
Diffuse 75 35 0.009*12 98 0.439
Presence of erythema 17 13 0.016*4 26 0.527
Presence of hypopigmentation 28 10 0.956 2 36 0.851
*p< 0.05.
Clinical analysis according to sex
Clinical characteristics were analysed according to sex
(Table 4). Fifteen patients were male and 139 patients were
female. Among preceding and associated symptoms,
preceding erythema was statistically more frequent in
women (p= 0.025). Henna hair dyes and other types of
hair dyes were more likely to be associated with aggravation
in female patients (p=0.027 and p=0.005, respectively).
Other clinical variables such as the age of diagnosis, time to
diagnosis, aggravating factors other than hair dye, Fitzpa-
trickskintype,locationofhyperpigmentation, and clinical
manifestations did not show any significant differences
between the two groups.
Clinical analysis according to hair dye use
Supporting Information: Table 1presents clinical
features analysed according to hair dye use. There were
61 patients who reported using hair dye before Riehl
melanosis development. Thirtyfour patients reported
using henna hair dye, 47 patients reported using hair dye
other than henna, and 20 patients used both products.
The age and sex are both statistically related to the hair
dye use (p= 0.001 for both). Among various locations,
involvement of the forehead was significantly related to
hair dye use (p< 0.001). Time to diagnosis was signifi-
cantly shorter in those who used hair dye (p= 0.001).
Other clinical variables such as preceding and associated
symptoms, aggravating factors other than hair dye,
location of hyperpigmentation other than the forehead,
and clinical manifestations did not show any significant
differences between the two groups.
Treatment and prognosis
Followup data were available in 110 patients. The
mean followup period was 11.4 months (range 248
months). Global assessment scale scores decreased
from 2.7 ± 0.6 to 1.8 ± 0.8 on average after treatment.
The average treatment response score according to the
percentage of pigment clearing was 0.9. There were 38
patients who showed a fair response (0%25%),
50 patients had a moderate response (26%50%), 17
patients showed a good response (51%75%), and 5
patients had an excellent response (76%100%)
(Figure 1). The overall cumulative response rate of
26% pigment clearing was 65.5%. According to
logistical regression analysis, a longer disease duration
(>3 months, p= 0.002) was a statistically significant
factor associated with poorer treatment response
(Table 5). On the other hand, aggravation by hair
dye other than henna, use of laser therapy, and a
longer followup period were found to be statistically
significant factors positively associated with treatment
response (p= 0.006, p= 0.015, and p=0.021, respec-
tively). Patients received a wide range of treatments.
Topical agents including steroids (49.1%), calcineurin
inhibitors (40.9%), blanching creams (41.8%), and
polydeoxyribonucleotide (PDRN) (29.1%) were used.
Oral medication such as systemic steroids (49.1%),
antihistamines (73.6%), and tranexamic acid (87.3%)
were prescribed. Laser therapy was performed in
63.6% of patients, including low fluence 1064nm
Nd:YAG laser toning (22.7%), 1064nm picosecond
laser therapy (7.3%), and needle radiofrequency laser
therapy (17.3%). However, no single therapy proved to
be a statistically significant factor in the treatment
Riehl melanosis is a cosmetically debilitating disorder
with significant psychosocial impacts on affected
patients because it manifests as hyperpigmentation
on exposed areas such as the face and neck. All
patients enrolled in this study had hyperpigmentation
limited to the face and neck to exclude lichen planus
pigmentosus (LPP) or ashy dermatosis, which can also
involve the trunk and limbs. However, it is difficult to
make a differential diagnosis among Riehl melanosis,
LPP, and ashy dermatosis. Generally, ashy dermatosis
develops at a younger age and more commonly
involves sunprotected areas such as the trunk and
proximal extremities and presents with an erythema-
tous border in early lesions.
LPP can present with
past or current evidence of lichen planus, can manifest
in intertriginous sites, and may present erythematous
borders; it mostly affects the forehead and temporal
area and shows dense bandlike lichenoid infiltra-
Whether these three diseases are distinct
entities or variants of the same disease has been a
topic of debate.
Another descriptive diagnosis to take into account is
erythrose peribuccale pigmentaire of Brocq, also referred
to as erythrosis pigmentosa faciei.
This syndrome occurs
predominantly in middleaged women, and a photo-
dynamic substance in cosmetics is probably responsi-
Diffuse, brownishred pigmentation develops
more or less symmetrically around the mouth but spares
a narrow perioral ring. It may extend to the centre of the
face and the forehead, and in some cases there are well
defined patches of pigmentation over the angles of the
jaw and the temples.
The erythematous component and
the intensity of the pigmentation may fluctuate over
short periods.
The pigmentation is usually persistent
but tends to fade gradually if the cause is eliminated.
Although only a few cases have been described, we
suspect that this entity can be included in the spectrum
of Riehl melanosis.
Unlike allergic contact dermatitis, Riehl melanosis is
usually preceded by either mechanical or chemical
stimulation and frequently accompanies barrier impair-
ment, resulting in enhanced penetration of causative
agents. In our study, dryness, which is a sign of damaged
barrier function, was found in 11.7% of patients, and
preceding erythema and itching were observed in about
half of the patients. Although various mechanical stresses
such as laser treatment, peeling, friction, exercise, and
overheating were aggravating factors, chemical stimuli
such as hair dyes and cosmetics were most commonly
found aggravating factors. In regard to the distribution of
the hyperpigmentation, the Uzone of the face (cheek,
perioral area, and chin) was more likely to be affected than
the Tzone (forehead and nose). This distribution is
probably related to the fact that the Tzone has a stronger
barrier function with a higher sebum level and lower
FIGURE 1 Clinical and histopathological features of a Riehl melanosis patient. (ac) A 61yearold woman who used hair dye every
6 months developed diffuse brownish maculopatches on her forehead, both cheeks, perioral area, and neck. The patient complained of an
itching sensation and previously had erythema. (df) The patient was prescribed transamine 250 mg three times a day and the
antihistamine ebastine 10 mg as well as a topical calcineurin inhibitor. A nanosecond 1064nm Nd:YAG laser (TriBeam; Jeisys Corp.) was
used with a zoom handpiece with a spot size of 7 mm, fluence of 1.53.0 J/cm
, a repetition rate of 10 Hz, and six passes. After 15 laser
treatments, the hyperpigmented lesions improved significantly. (g, h) The histopathological features of the lesions suggested interface
dermatitis with dermal melanophages and mild perivascular inflammation (g: Hematoxylineosin stain; magnification: ×100,
h: Hematoxylineosin stain; magnification: ×400).
transepidermal water loss.
Riehl melanosis is known to
present as diffuse pigmentation but reticulated or spotty
lesions are also observed.
Most of our study patients
had a diffuse pattern but spotty or reticulated lesions were
also found as a single pattern or combined with other types.
The common allergens observed in Riehl melanosis
patients include aniline dyes, bactericides, fragrances,
and fixatives such as benzyl salicylate.
Despite the
fact that the exact pathogenesis and aetiology of Riehl
melanosis still remain controversial, previous studies
TABLE 5 Prognostic factors influencing the treatment response in the patients with Riehl melanosis
Variables Category Odds ratio
95% confidence
interval pValue
Gender Female Reference
Male 6.224 0.61363.238 0.122
Age (years) >50 Reference
50 0.201 0.0391.041 0.056
Duration (mo) 3 Reference
>3 0.104 0.0240.451 0.002*
Fitzpatrick skin type III Reference
IV 0.617 0.1153.316 0.574
Preceding symptoms Erythema 5.247 0.85032.379 0.074
Itching 0.583 0.1392.444 0.460
Facial flushing 1.203 0.1708.488 0.853
Associated symptoms and signs Photosensitivity 4.635 0.31967.420 0.262
Dryness 0.230 0.0222.455 0.224
Aggravating factors Henna hair dye 0.233 0.0272.004 0.184
Other hair dye 5.033 1.57816.056 0.006*
Laser treatment 24.793 0.1863297.618 0.198
Friction 3.537 0.24451.250 0.354
Cosmetics 1.703 0.22113.136 0.609
Exercise 0.205 0.0085.319 0.340
Sunlight 0.823 0.0957.154 0.860
Treatment Topical steroid 2.145 0.5678.109 0.261
Topical calcineurin inhibitor 0.457 0.0573.655 0.461
Topical blanching cream 0.813 0.1863.557 0.784
Systemic steroid 1.084 0.2404.900 0.916
Antihistamine 0.408 0.0622.678 0.350
Tranexamic acid 1.190 0.1688.452 0.862
PDRN 3.179 0.30732.924 0.332
Laser treatment 4.397 1.33114.523 0.015*
NdYAG 0.286 0.0801.017 0.053
Pico 1064 0.094 0.0033.210 0.190
Needle RF 0.668 0.0538.464 0.756
Followup period 3 Reference
>3 3.399 1.0911.450 0.021*
*p< 0.05.
have suggested that allergic sensitization induced by
repeated exposure to low concentrations of particular
chemicals, including fragrance or dye, could be the
major cause.
In this study, 76.5% of patients
revealed positive patch tests, which is consistent with
previous studies.
However, the clinical rele-
vance of positive test results is doubtful in most cases.
Despite the fact that half of the patients recalled that
their lesions were related to hair dye use, p
phenylenediamine and henna hair dye showed
reactive patch tests in only one patient each. More-
over, a recent study on Riehl melanosis suggested that
elevated transient receptor potential vanilloid 1
(TRPV1) linked the symptoms of Riehl melanosis
patients to inflammationrelated hyperpigmentation
through Ca
/protein kinase C/tyrosinase activity,
which implies that irritation is important in the
development and aggravation of Riehl melanosis.
In this study, Riehl melanosis in older patients was
related to hair dye use and more likely to manifest as
spotty hyperpigmentation, while in younger patients the
disorder tended to show erythema. Since the barrier
functions of skin decrease with age, a young patient who
develops Riehl melanosis may have been exposed to
preceding stimuli that damaged the skin barrier, result-
ing in erythema. In regard to sex, female patients are
more likely to have had preceding erythema and hair dye
use than male patients. Lastly, patients who developed
Riehl melanosis after hair dye use developed lesions
more frequently on the forehead and that were diagnosed
more quickly. This is probably because hair dyes can
result in the relatively rapid development of Riehl
melanosis or because dyspigmentation after henna hair
dye has been a social issue in Korea, resulting in
enhanced awareness.
Among a wide range of factors, long disease
duration was associated with poor treatment response,
while aggravation by hair dye other than henna, laser
therapy, and longer followup periods was related to
good treatment response. In this study, tranexamic
acid and antihistamine were the most frequently
prescribed drugs, and laser therapy was used in
63.6% of patients. Despite the fact that no single
treatment proved to be a statistically significant factor
in the treatment response, laser therapy was associ-
ated with better outcomes. Although standardization
of laser therapy has not been established in Riehl
melanosis patients, two previous studies demonstrated
the efficacy of intense pulsed light therapy (IPL) and
dual pulsed Qswitched Nd:YAG laser therapy for
Riehl melanosis.
More studies are needed to
compare the efficiency of various laser therapies in
Riehl melanosis patients.
In summary, we investigated clinical characteristics
of recent Korean Riehl melanosis patients and found that
clinical manifestations of Riehl melanosis differ to some
extent according to age, sex, and hair dye use. Moreover,
detailed history taking in regard to disease duration and
aggravating factors, as well as the use of extended laser
therapy, can be important for the management of Riehl
The patients in this manuscript have given written
informed consent to the publication of their case
details. This study had no funding sources.
The authors declare no conflict of interest.
The data that support the findings of this study are
available on request from the corresponding author, Sun
Eun Chang.
Myoung Eun Choi
Youngkyoung Lim
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Additional supporting information can be found online
in the Supporting Information section at the end of this
How to cite this article: Choi ME, Lim Y, Lee
WJ, Won CH, Lee MW, Chang SE. Characteristics
of Riehl melanosis in an ethnic Asian population: a
comparative study according to age, sex, and hair
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Full-text available
Pigmented contact dermatitis (PCD) is a noneczematous variant of allergic contact dermatitis, and benzyl salicylate is one of its causes. This type of PCD shows nonlichenoid interface dermatitis with pigment incontinence. We aimed to characterize the earliest histopathological changes of this reaction. A 51-year-old man presented with persistent facial eruption composed of hyperpigmented and hypopigmented macules due to exposure to benzyl salicylate present in his aftershave. The biopsies obtained from hyperpigmented and hypopigmented macules, and from the positive patch test site to benzyl salicylate, showed a nonlichenoid focal vacuolar interface dermatitis with mononuclear cells in the papillary dermis and around the pilosebaceous units, along with melanophages. A MART-1 immunostain showed intact melanocytes in all 3 biopsies. A Fontana-Masson stain demonstrated intact melanin in the basal cell layer of a facial hyperpigmented macule and the patch test site, but melanin was reduced in the biopsy taken from a hypopigmented facial macule. There were more epidermal and dermal CD1a+ Langerhans cells in the patch test biopsy than in the other 2 biopsies. Most of the mononuclear cells were CD3+. The CD4+ to CD8+ ratio was approximately 1:1 in the facial macules; yet, CD4+ cells outnumbered CD8+ cells in the patch test biopsy. There were a few TIA-1+ cells in all 3 biopsies. In conclusion, the earliest histopathological and immunophenotypical events in PCD due to benzyl salicylate are similar to those of longer-standing lesions, i.e., a nonlichenoid focal interface dermatitis involving the epidermis and pilosebaceous unit, along with dermal melanophages.
Full-text available
Background: Pigmented cosmetic dermatitis (PCD) is frequently encountered in dark-skinned individuals as gradual hyperpigmentation on the face without preceding erythema or itching. Little is known about the allergen profile in PCD. Objectives: The aim of the study was to describe the clinical profile and common allergens in PCD and allergic contact dermatitis (ACD) to cosmetics in Delhi. Methods: Records of patients suspected of PCD and ACD to cosmetics were analyzed. All patients were patch tested with the Indian standard series, Indian cosmetic and fragrance series, and personal cosmetics and, in relevant cases, hairdresser series. Results: One hundred six patients were analyzed. Patch test was positive in 77 cases (72.6%). Cetrimonium, gallate mix, thiomerosal, and skin lightening creams were more frequently positive in cases of PCD (P = 0.019-0.003), whereas p-phenylenediamine, toluene-2,5 diamine sulfate, p-aminophenol, m-aminophenol, and nitro-p-phenylenediamine were predominantly positive in ACD to cosmetics (P < 0.001). Conclusions: Preservatives, antioxidants, and skin lightening creams seem to play a role in causation of PCD, whereas hair dye allergens cause ACD to cosmetics in India.
Full-text available
Facial dyspigmentation in Asian women often poses diagnostic and therapeutic challenges. Recently, a distinctive bilateral hyperpigmentation of face and neck has occasionally been observed. This study was performed to investigate the clinico-pathological features of this dyspigmentation as well as proper treatment approaches. We retrospectively investigated the medical records including photographs, routine laboratory tests, histopathologic studies of both lesional and peri-lesional normal skin and patch test of thirty-one patients presented acquired bizarre hyperpigmentation on face and neck. The mean age of patients was 52.3 years and the mean duration of dyspigmentation was 24.2 months. In histologic evaluations of lesional skin, a significantly increased liquefactive degeneration of basal layer, pigmentary incontinence and lymphocytic infiltration were noted, whereas epidermal melanin or solar elastosis showed no statistical differences. Among 19 patients managed with a step-by-step approach, seven improved with using only topical anti-inflammatory agents and moisturizer, and 12 patients gained clinical benefit after laser therapy without clinical aggravation. Both clinical and histopathologic findings of the cases suggest a distinctive acquired hyperpigmentary disorder related with subclinical inflammation. Proper step-by-step evaluation and management of underlying subclinical inflammation would provide clinical benefit.
Background: Henna is a vegetable hair dye that can be used by individuals who are sensitized to oxidative dyes due to low allergenicity. The reported incidence of slate-grey facial dyspigmentation following the use of henna hair dye is extremely rare. Objectives: This study aimed to identify the clinical, dermoscopic, and histopathological features of slate-grey facial dyspigmentation following the use of henna hair dye in Korean patients. Materials & methods: We identified all patients who presented with slate-grey facial dyspigmentation following usage of henna hair dye. Patients were further evaluated for clinical, dermoscopic, and histopathological findings along with their patch test results. Results: All 11 patients were females with Fitzpatrick’s skin phototype III or IV. Prominent slate-grey-coloured dyspigmentation on the lateral side of the face and neck was most common in eight (72%) patients. Under dermoscopic examination, a pseudo-network with grey dots was observed in all patients. Histopathological examination revealed liquefaction degeneration of the epidermal basal layer and pigmentary incontinence in the papillary dermis in all patients. The diagnosis of pigmented contact dermatitis following usage of henna was made based on the clinical, dermoscopic, and histopathological findings in all patients. Conclusion: Pigmented contact dermatitis associated with henna occurs mostly in middle-aged women and requires long-term treatment. Therefore, careful attention should be paid when henna is used to dye hair in this age group.
Postinflammatory hyperpigmentation (PIH) commonly occurs after various endogenous and exogenous stimuli, especially in dark-skinned individuals. PIH is one of the most common complications of procedures performed using laser and other light sources. The severity of PIH is determined by the inherent skin color, degree and depth of inflammation, degree of dermoepidermal junction disruption, inflammatory conditions, and the stability of melanocytes, leading to epidermal and dermal melanin pigment deposition. The depth of melanin pigment is the key factor to predict prognosis and treatment outcome. Epidermal hyperpigmentation fades more rapidly than dermal hyperpigmentation. Various inflammatory disorders can eventually result in PIH. The evaluation of pigmentation using noninvasive tools helps define the level of pigmentation in the skin, pigmentation intensity, and guides therapeutic approaches. This first article in this 2-part series discusses the epidemiology, pathogenesis, etiology, clinical presentation, differential diagnoses, and investigation using noninvasive assessment techniques that objectively determine the details of pigmentation. Copyright © 2017 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.
Background: Erythema dyschromicum perstans (EDP)/Ashy dermatosis (AD), Lichen planus pigmentosus (LPP) and Pigmented contact dermatitis (PCD) are common skin diseases featuring abnormal pigmentation which have overlapping clinical features. Objective: To search for differences in the natural history, clinical features, histopathology and relevant contact allergens in patients those were clinically diagnosed as AD, LPP and PCD in our outpatient clinic. Method: 43 patients were enrolled into the study. Patients' demographic details, histological findings, DIF staining, provisional and histology diagnosis were recorded. Closed patch tests with standard fragrance and cosmetic series allergens were performed in all patients. Result: 36 of the patients were female and all of them had dark skin complexions (Fitzpatrick's skin type IV-V), as normally found in AD and LPP. The most common histological finding was pigmentary alteration followed by lichenoid infiltration. DIF staining was positive in 6 out of 21 cases, the most common pattern being IgM colloid bodies. Patients with a provisional diagnosis of AD and LPP had positive patch tests in 40 and 36.36% of cases, respectively. Conclusion: We have found some similarities and differences between these 3 clinically and histologically overlapping pigmentary disorder. Clinical history, histopathology and DIF are necessary together for making the diagnosis. Patch testing should be conducted in all cases that present with AD or LPP.