10.5826/dpc.1204a163
Introduction: Vitiligo is an acquired disease of complex pathogenesis, in which the immunologic attack to the skin and hair follicle melanocytes leads to areas of depigmentation and leukotrichia, respectively.
Objectives: To study the dermoscopic features of the hair changes in vitiligo lesions in comparison to perilesional control areas and in relation to disease duration.
Methods: Forty-seven patients with both old and recent vitiligo lesions were included. Dermoscopic features of hair within the lesions were examined and compared to those in perilesional non depigmented skin of the same patient.
Results: Hair density (P &lt; 0.001), terminal hair rate (P = 0.011), terminal to vellus hair ratio (P = 0.029) and mean hair shaft thickness (P = 0.031) were significantly decreased, whereas vellus hair rate (P = 0.011) was significantly increased in old vitiligo lesions compared to their respective control areas. The frequency of broken hair was significantly higher in old lesions (P &lt; 0.001), while that of upright re-growing hair was significantly higher in recent lesions (P = 0.016).
Conclusions: Hair involvement in vitiligo lesions is not only limited to the development of leukotrichia. Other subtle changes in hair density, anagen and telogen hair rates, and mean hair thickness can be detected. These changes may serve as objective clues to the duration of the lesions.
text/xml
2160-9381
2119
en
Hoda  Moneib
https://creativecommons.org/licenses/by-nc/4.0
Dermatology Practical & Conceptual
Alopecia areata incognita
Videodermoscopic changes of the hair in vitiligo lesions in relation to disease duration
Text.Serial.Journal
https://dpcj.org/index.php/dpc
Original Article
2022-10-31
2021-10-26
2022-10-31
2022-11-29
e2022163
Dermatol Pract Concept
Introduction: Vitiligo is an acquired disease of complex pathogenesis, in which the immunologic attack to the skin and hair follicle melanocytes leads to areas of depigmentation and leukotrichia, respectively.
Objectives: To study the dermoscopic features of the hair changes in vitiligo lesions in comparison to perilesional control areas and in relation to disease duration.
Methods: Forty-seven patients with both old and recent vitiligo lesions were included. Dermoscopic features of hair within the lesions were examined and compared to those in perilesional non depigmented skin of the same patient.
Results: Hair density (P &lt; 0.001), terminal hair rate (P = 0.011), terminal to vellus hair ratio (P = 0.029) and mean hair shaft thickness (P = 0.031) were significantly decreased, whereas vellus hair rate (P = 0.011) was significantly increased in old vitiligo lesions compared to their respective control areas. The frequency of broken hair was significantly higher in old lesions (P &lt; 0.001), while that of upright re-growing hair was significantly higher in recent lesions (P = 0.016).
Conclusions: Hair involvement in vitiligo lesions is not only limited to the development of leukotrichia. Other subtle changes in hair density, anagen and telogen hair rates, and mean hair thickness can be detected. These changes may serve as objective clues to the duration of the lesions.
Hoda  Moneib
2022/10/31
10.5826/dpc.1204a163
e2022163
Department of Dermatology, and Venereology, Faculty of Medicine, Ain Shams University, Cairo, Egypt
2160-9381
Alopecia areata incognita
en
e2022163
Anbar TS, Westerhof W, Abdel-Rahman AT, El-Khayyat MA. Evaluation of the effects of NB-UVB in both segmental and non-segmental vitiligo affecting different body sites. Photodermatol Photoimmunol Photomed. 2006;22(3):157-163. DOI: 10.1111/j.1600-0781.2006.00222.x. PMID: 16719871.
Videodermoscopic changes of the hair in vitiligo lesions in relation to disease duration
https://dpcj.org/index.php/dpc/article/download/2119/1778
   Videodermoscopic Changes of the Hair in Vitiligo
       Lesions in Relation to Disease Duration
     Tag Anbar1, Hamza Abdelraouf1, Ahmed Abd Elfattah Afify2, Maha Hussien Ragaie1,
                         Amira Abulfotooh Eid3, Hoda Moneib2


1 Department of Dermatology and Venereology, Faculty of Medicine, Al-Minya University, Al-Minya, Egypt
2 Department of Dermatology, and Venereology, Faculty of Medicine, Ain Shams University, Cairo, Egypt
3 Department of Dermatology, Venereology and Andrology, Faculty of Medicine, Alexandria University, Alexandria, Egypt



Key words: vitiligo, videodermoscopy, hair changes, alopecia areata incognita
Citation: Anbar T, Abdelraouf H, Afify AA, Ragaie MH, Eid AA, Moneib H. Videodermoscopic changes of the hair in vitiligo lesions in
relation to disease duration. Dermatol Pract Concept. 2022;12(4):e2022163. DOI: https://doi.org/10.5826/dpc.1204a163
Accepted: January 30, 2022; Published: October 2022
Copyright: ©2022 Anbar et al. This is an open-access article distributed under the terms of the Creative Commons Attribution-
NonCommercial License (BY-NC-4.0), https://creativecommons.org/licenses/by-nc/4.0/, which permits unrestricted noncommercial use,
distribution, and reproduction in any medium, provided the original authors and source are credited.
Funding: None.
Competing interests: None.
Authorship: All authors have contributed significantly to this publication.
Corresponding author: Amira Abulfotooh Eid, Department of Dermatology, Venereology and Andrology, Faculty of Medicine, Alexandria
University, Elazarita 21521, Alexandria, Egypt. Tel: +2 03 4872150 E-mail: amira.eid@alexmed.edu.eg; dramiraeid@yahoo.co.uk




  ABSTRACT             Introduction: Vitiligo is an acquired disease of complex pathogenesis, in which the immunologic
                       attack to the skin and hair follicle melanocytes leads to areas of depigmentation and leukotrichia,
                       respectively.
                       Objectives: To study the dermoscopic features of the hair changes in vitiligo lesions in comparison to
                       perilesional control areas and in relation to disease duration.
                       Methods: Forty-seven patients with both old and recent vitiligo lesions were included. ­Dermoscopic
                       features of hair within the lesions were examined and compared to those in perilesional non
                       ­depigmented skin of the same patient.
                       Results: Hair density (P < 0.001), terminal hair rate (P = 0.011), terminal to vellus hair ratio
                       (P = 0.029) and mean hair shaft thickness (P = 0.031) were significantly decreased, whereas vellus hair
                       rate (P = 0.011) was significantly increased in old vitiligo lesions compared to their respective control
                       areas. The frequency of broken hair was significantly higher in old lesions (P < 0.001), while that of
                       upright re-growing hair was significantly higher in recent lesions (P = 0.016).
                       Conclusions: Hair involvement in vitiligo lesions is not only limited to the development of ­leukotrichia.
                       Other subtle changes in hair density, anagen and telogen hair rates, and mean hair thickness can be
                       detected. These changes may serve as objective clues to the duration of the lesions.




Original Article | Dermatol Pract Concept. 2022;12(4):e2022163                                                                        1
Introduction                                                           An informed consent was signed by each patient after the
                                                                    technical and scientific basis of the research project and the
Vitiligo is an acquired chronic depigmenting autoimmune             steps of the procedure were explained in details. The r­ esearch
disease of the skin and hair; in which progressive destruction      was approved by the local Medical Ethics C
                                                                                                             ­ommittee
of melanocytes occur. Loss of melanocytes from the e­ pidermis      (approval number: 0303878/14/03/2018).
is the cause of leukoderma, and if the process extends to              Each patient was examined clinically and two vitiligo le-
involve the active bulbar melanocytes, leukotrichia will de-        sions (one old and one recent) were selected for examination;
velop [1]. In addition to the characteristic skin involvement       recent lesions were of a duration of less than two years and
in vitiligo, other associated manifestations including ocular       old lesions were of a duration of two or more years [14].
and audiological findings have been described. [2-4].               Lesions and surrounding control areas were photographed
    Several theories have been put forward to explain the           using a digital camera (Samsung ST66, 16 megapixels);
etiopathogenesis of vitiligo; among which autoimmunity is           photos were taken from a constant distance and under sim-
the leading one. The increased prevalence of several autoim-        ilar photographing conditions. The hair within the lesions
mune diseases in vitiligo patients as well as their first degree    was evaluated using the Medicam 1000 video-­dermoscope
relative has been reported, which suggests a general genetic        (Fotofinder). Three shots were taken with the video-
                                                                    ­
predisposition to autoimmunity [4,5]. One of the commonly           dermoscope (20X magnification) from the vitiligo lesion and
associated autoimmune diseases with vitiligo is alopecia            three shots were taken from perilesional normally pigmented
areata (AA) [6]. Both diseases have common genetic risk fac-        skin (control) after Wood’s light examination was done to
tors and share certain similarities regarding their pathogene-      exclude the presence of subclinical vitiligo. The d
                                                                                                                      ­ ermoscopic
sis [7,8]. Several reports of colocalization of vitiligo and AA     photos were evaluated by Trichoscale® Pro program
especially on the scalp exist in the literature [9-12], with skin   ­(Fotofinder). The report of every photo included data about
biopsies exhibiting features of both diseases [12]. Moreover,       hair density, anagen and telogen hair rates, terminal and
relatively decreased hair density was previously reported in a      vellus hair rates and the mean hair shaft thickness. The means
depigmented area on the scalp that was also associated with         of the collected data from the reports of the three shots taken
histopathologic features suggestive of AA [13]. On revising         from every lesional and perilesional normally pigmented
the literature, no studies detailing the dermoscopic features       skin were determined. In addition, ­videodermoscopic ­photos
of the hair in vitiligo lesions in different body areas could       of the studied lesions and perilesional control areas were
be found.                                                           ­evaluated for the presence of dermoscopic signs of alopecia
                                                                    areata such as black dots, tapering hair, broken hair, ­yellow
                                                                    dots, short vellus hair, circular (pigtail) hair, upright re-
Objectives
                                                                    growing hair and Pohl-Pinkus constriction.
The objective of this study was to explore the dermoscopic
features of the hair in vitiligo lesions in different body sites    Statistical Analysis
and their relation to disease duration.                             The collected data was analyzed using the statistical package for
                                                                    Social Science (IBM SPSS Statistics for Windows, Version 22.0;
                                                                    IBM Corp.). Quantitative variables were tested for normality
Methods                                                             of distribution using the Kolmogorov-Smirnov test and were
This study included 47 non segmental vitiligo patients of           expressed as median and interquartile range (IQR). Categorical
both sexes with more than one patch of vitiligo.                    variables were expressed as frequencies and percentages. Paired
    Exclusion criteria for lesion choice:                           nominal variables were compared u
                                                                                                    ­sing McNemar-Bowker
                                                                    test. Differences between paired c­ ontinuous data (lesions and
1. Lesions in areas anatomically known to have absent or            control areas) were tested using the ­Wilcoxon signed rank test.
    sparse hair, eg palms, soles, mucous membranes, fingers         The strength of association between the two quantitative vari-
    and dorsum of the foot.                                         ables was assessed using Spearman method. A P value less than
2. Scalp lesions, as it is difficult to evaluate vitiligo without   0.05 was considered statistically significant.
    shaving due to high hair density.
3. If all lesions in the same patient were of less than or more
                                                                    Results
    than two-year duration.
4. Segmental vitiligo.                                              The age of the patients ranged from 7 to 55 years (mean:
5. Patients with a concomitant diagnosis of AA or with his-         26.38 ± 14.5 years). Twenty-four males (51%) and 23 females
    tory of previously developing AA.                               (49%) were enrolled in the study. The mean duration of the




2                                                                       Original Article | Dermatol Pract Concept. 2022;12(4):e2022163
included recent vitiligo lesions (< 2 years) was 6.28 ± 2.37           anagen and telogen hair rates and anagen to telogen ratio was
months while the mean duration of the included old vitiligo            detected (P = 0.195, 0.195 and 0.357, respectively) (Table 2).
lesions (≥ 2 years ) was 46.8 ± 18.72 months.                              The decrease in hair density and thickness in old vitiligo
                                                                       lesions compared to their respective control sites is shown
Hair Changes in Recent Lesions                                         in Figure 1.
In recent vitiligo lesions, anagen hair rate, anagen to ­telogen
ratio, terminal hair rate and terminal to vellus ratio were            Dermoscopic Signs of the Hair in Vitiligo Lesions
lower than those in the respective control areas, but the              In old lesions, the most commonly encountered sign was bro-
difference was not significant (P = 0.352, 0.783, 0.603                ken hair, which was seen in 51.1% of the patients, followed
and 0.656, respectively). Furthermore, hair density, telogen           by pig tail hair in 31.9% of the patients. Meanwhile, tapering
hair rate, and vellus hair rate were higher in recent vitiligo         hair and Pohl-Pinkus constriction were the least commonly
lesions compared to control areas, and the difference was              encountered signs, as each was detected in 8.5% of patients.
also not significant (P = 0.151, 0.352 and 0.603, respectively)        In recent vitiligo patches, short vellus hair was detected in
(Table 1).                                                             31.9% of the patients followed by upright re-growing hair in
                                                                       29.8% of the patients. The least commonly encountered sign
Hair Changes in Old Lesions                                            was tapering hair that was detected in 4.3% of the patients.
In old vitiligo lesions, hair density, terminal hair rate, termi-      None of the recent vitiligo patches showed Pohl-Pinkus
nal to vellus ratio and mean hair thickness were significantly         constriction. The presence of broken hair was significantly
lower (P < 0.001, 0.011, 0.029 and 0.031, respectively),               higher, whereas the presence of upright regrowing hair was
whereas vellus hair rate was significantly higher (p=0.011)            significantly lower in old patches compared to recent patches
than in the perilesional control areas. No significant differ-         (P <0.001 and 0.016, respectively) (Table 3). On comparing
ence between old patches and their control areas regarding             old vitiligo lesions to their respective controls, the frequency



        Table 1. Comparison between hair changes in recent vitiligo patches and their respective
                                          control patches.
                                            Recent patches (N = 47)              Control of recent patches (N = 47)             P
 Hair density (hair/cm2)                      52.00 (23.20 – 81.90)                       45.40 (17.70 – 96.30)              0.151
 Anagen hair rate (%)                         51.70 (33.10 – 65.30)                       53.50 (37.50 – 66.70)              0.352
 Telogen hair rate (%)                        48.30 (34.70 – 66.90)                       46.50 (33.30 – 62.50)              0.352
 Anagen to telogen ratio                        1.07 (0.49 – 1.88)                             1.15 (0.60 – 2.0)             0.783
 Terminal hair rate (%)                         5.60 (0.0 – 19.40)                             6.70 (0.0 – 18.0)             0.603
 Vellus hair rate (%)                         94.40 (80.60 – 100.0)                       93.30 (82.0 – 100.0)               0.603
 Terminal to vellus ratio                        0.06 (0.0 – 0.24)                             0.07 (0.0 – 0.22)             0.656
 Mean thickness (mm)                          0.028 (0.026 – 0.031)                       0.028 (0.025 – 0.031)              0.414

Data are expressed as median (interquartile range); P value for ­Wilcoxon Signed Ranks Test.



Table 2. Comparison between hair changes in old vitiligo patches and their respective control patches.
                                           Old patches (N = 47)                 Control of old patches (N = 47)                p
 Hair density (hair/cm2)                   33.20 (12.20 – 56.50)                      78.60 (26.60 – 156.10)                < 0.001
 Anagen hair rate (%)                      48.10 (40.0 – 70.60)                       61.60 (45.60 – 70.20)                  0.195
 Telogen hair rate (%)                     51.90 (29.40 – 60.0)                       38.40 (29.80 – 54.40)                  0.195
 Anagen to telogen ratio                     0.92 (0.67 – 2.40)                         1.60 (0.84 – 2.36)                   0.357
 Terminal hair rate (%)                     10.30 (0.0 – 19.30)                        17.10 (8.80 – 38.50)                  0.011
 Vellus hair rate (%)                      89.70 (80.70 – 100.0)                      82.90 (61.50 – 91.20)                  0.011
 Terminal to vellus ratio                    0.11 (0.0 – 0.24)                          0.21 (0.10 – 0.63)                   0.029
 Mean thickness (mm)                       0.029 (0.025 – 0.031)                      0.031 (0.029 – 0.035)                  0.031

Data are expressed median (interquartile range); P value for Wilcoxon Signed Ranks Test




Original Article | Dermatol Pract Concept. 2022;12(4):e2022163                                                                        3
Figure 1. Decreased hair density and thickness in old vitiligo lesions compared to their respective control sites (magnification x20).
(A-C) Videodermoscopic photos of the hair changes in the old vitiligo lesions. (D-F) Video-dermoscopic photos of respective control sites.
(A, B, D and E on the nape, C and F on the leg).


     Table 3. Comparison between old and recent vitiligo patches regarding dermoscopic features
                                  of alopecia areata incognita.
                                                           Old patches
                                                              (N =4 7)                Recent patches (N = 47)                    P
 Black dots, N (%)                                           6 (12.8%)                        9 (19.1%)                       0.250
 Tapering hair, N (%)                                        4 (8.5%)                          2 (4.3%)                       0.500
 Broken hair, N (%)                                         24 (51.1%)                        8 (17.0%)                      < 0.001
 Yellow dots, N (%)                                           8 (17%)                         6 (12.8%)                       0.500
 Short vellus hair, N (%)                                   11 (23.4%)                        15 (31.9%)                      0.125
 Circular (pig tail) hair, N (%)                            15 (31.9%)                        11 (23.4%)                      0.125
 Upright re-growing hair, N (%)                              7 (14.9%)                        14 (29.8%)                      0.016
 Pohl-Pinkus constrictions, N (%)                            4 (8.5%)                          0 (0.0%)                       0.125

P for McNemar-Bowker test



4                                                                           Original Article | Dermatol Pract Concept. 2022;12(4):e2022163
of broken hair, yellow dots and pig tail hair was significantly     been attributed to an increase in cytotoxic CD8+NKG2D+
higher in the former (P < 0.001, 0.031, 0.004, respectively).       T cells together with over expression of interferon gamma
Meanwhile, black dots and pig tail hair were significantly          (IFN-γ), with the involvement of the JAK-STAT signaling
higher in recent vitiligo lesions than in control areas (P =        pathway [8]. In addition, it has been shown that the immu-
0.004 and 0.031, respectively).                                     nologic attack of CD8+ T-cells on follicular melanocytes can
                                                                    in some instances result in both depigmentation and hair

Conclusions                                                         loss [28]. Clinically, the fact that non-pigmented hairs are
                                                                    usually spared in alopecia areata, and regrowing hairs are
In vitiligo, skin involvement usually precedes hair involve-        initially depigmented, further links alopecia areata to mela-
ment. Nevertheless, lesions where leukotrichia developed            nocytes [29].
prior to skin depigmentation have been reported, which was             It has been proposed that autoreactive T-cells against
believed to result from preferential involvement of follicular      melanogenesis-associated proteins are responsible for spar-
melanocytes in such cases [15,16].                                  ing white hairs in AA and for the transient regrowth of
    Several changes have been reported in association with          hypo-pigmented hairs. However, there is always an exception
vitiligo that include ocular, auditory and even nail changes        to the rule; as in some patients non-pigmented hairs were
[2,3,17]. Apart from the color change, little is known about        lost as well, and in others re-growing white hairs persisted.
the changes that could occur in the hair within vitiligo lesions.   Furthermore, some patients never experience hair regrowth
Reports of AA and vitiligo existing in the same individual are      following the initial attack. These different outcomes suggest
present [18], and several reports of co-localization of vitiligo    the existence of various antigens and various pathways in-
and AA exist in the literature, most of which describe com-         volved that ultimately determine the fate of the immunologic
plete loss of hair in the depigmented patch with few white          attack on the hair follicle [30].
peripheral hairs. On histopathologic examination of the in-            Unlike the findings of Walker et al. [13], hairs within the
volved areas, features of vitiligo and AA were detected. Most       examined lesions were not exclusively depigmented, and in
of these cases were reported in young age and were mostly           addition to decreased density, they also exhibited decreased
located on the scalp [9-12,19]. Walker et al. reported slight       thickness and decreased terminal to vellus ratio owing to an
reduction in hair density within a localized area of poliosis       increase in vellus hair rate and a decrease in terminal hair
on the scalp with depigmentation of the underlying skin in a        rate. These changes, however, were only detected in old le-
male patient. Skin biopsies revealed features of both vitiligo      sions. Unfortunately, the software program used in the cur-
and AA [13]. However, none of those reports studied the der-        rent study digitally documents the essential hair parameters
moscopic hair changes within the vitiligo lesions.                  of all hairs in the lesion regardless of their color; accordingly,
    In the present study, the anagen-to-telogen and the             determining if the detected changes were influenced by hair
terminal-to-vellus ratios were lower in both old and recent         color was not possible.
areas compared to their respective controls but the differ-            The role of disease duration in vitiligo has been previ-
ence was significant only in the terminal-to-vellus ratio in        ously studied and the presence of melanocytes in the hair
old lesions. Furthermore, both old and recent vitiligo lesions      follicles in vitiligo lesions was reported to be inversely
exhibited dermoscopic findings such as yellow dots, bro-            correlated with disease duration [31]. In addition, shorter
ken hair, short vellus hair, upright regrowing hair and cir-        disease durations were associated with better treatment re-
cular hair. These detected changes exhibit a certain degree         sponse to phototherapy [32]. In the present study, old and
of similarity to hair changes previously reported in alope-         recent vitiligo lesions were compared with their respective
cia areata incognita (AAI), which is characterized by the           controls. All significant videodermoscopic hair changes were
absence of a smooth bald surface, increased telogen hairs           exclusively seen in old vitiligo lesions.
[20], yellow dots, upright regrowing hairs [21], black dots,           These findings further point to the possible influence of
short vellus hair, broken hair, and tapered hair [21-24]. AAI       disease duration in vitiligo. It seems that the insult to vitiligo
usually shows increased proportion of telogen and vellus            skin is done through two waves with two different onsets,
hairs [25], resulting in decreased terminal-to-vellus and an-       a first wave affecting epidermal melanocytes resulting in
agen-to-telogen ratios in patients compared to normal sub-          leukoderma, followed by a second wave affecting the hair
jects [21,26,27].                                                   leading to subtle hair changes, and if the insult of this wave
    The similarities between hair changes detected in the           is severe enough, leukotrichia can occur. The possibility that
present study and those reported in AAI could be explained          these hair changes could be the forerunners of leukotrichia
by the proposed immunologic link between vitiligo and AA;           remains to be determined.
as both diseases are considered cell mediated autoimmune               To conclude, this study demonstrated that the hair in-
diseases in which disease induction, at least in part, has          volvement within vitiligo patches is not merely a color



Original Article | Dermatol Pract Concept. 2022;12(4):e2022163                                                                      5
change, and that these changes may serve as an objective                     13. Walker A, Mesinkovska NA, Boncher J, Tamburro J, Bergfeld
clue to the duration of vitiligo lesions. The resemblance be-                    WF. Colocalization of vitiligo and alopecia areata presenting
                                                                                 as poliosis. J Cutan Pathol. 2015;42(2):150-154. DOI: 10.1111
tween the detected changes and some of the known features
                                                                                 /cup.12437. PMID: 25388912.
of AAI adds a new item to the list of similarities between
                                                                             14. Brazzelli V, Antoninetti M, Palazzini S, Barbagallo T, De S­ ilvestri
AA and vitiligo. Accordingly, further research combining                         A, Borroni G. Critical evaluation of the variants influencing
dermoscopic examination with histopathologic evaluation                          the clinical response of vitiligo: study of 60 cases treated with
of the hair changes in vitiligo lesions and studying the re-                     ­ultraviolet B narrow-band phototherapy. J Eur Acad ­Dermatol
lation of these changes to disease activity and severity is                       Venereol. 2007;21(10):1369-1374. DOI: 10.1111/j.1468-
                                                                                  3083.2007.02278.x. PMID: 17958843.
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                                                                             15. Gan EY, Cario-Andre M, Pain C, et al. Follicular vitiligo: A
                                                                                  ­report of 8 cases. J Am Acad Dermatol. 2016;74(6):1178-1184.
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Original Article | Dermatol Pract Concept. 2022;12(4):e2022163                                                                              7
