Role of Trichoscopy in Evaluation of Alopecia Areata: A Study in a Tertiary Care Referral Centre in the Eastern India.

Background: Alopecia areata is an autoimmune disorder affecting the hair-bearing sites of the body. Trichoscopy has recently been practiced in the diagnosis of alopecia areata. Aim: To elicit trichoscopy patterns in alopecia areata and to find out any correlation of trichoscopic findings with disease severity.
Methods: Trichoscopy was done on clinically diagnosed cases of alopecia areata and on age and sex-matched controls without hair disorders by using a DL1 dermoscope (magnification: ×10). Observed dermoscopic findings were analyzed to find the correlation with disease severity.
Results: In total, 87 cases and 60 controls were included in the study with the mean age for cases being 25.47 ± 14.07 years. There was male predominance of cases (51; 58.62%). Alopecia in multiple patches was the most common type (42; 48.27%), and scalp was the most common site of involvement (79; 90.8%). Yellow dots (YD), black dots (BD), broken hairs (BH), circle hair (CH), and tapering hairs (TH) or exclamation hair (EH) were found to be statistically significant findings in alopecia areata as compared to controls. Circle hair was significantly associated with total severity of alopecia areata (P = 0.041). Yellow dots had a positive correlation with the number of episodes of alopecia areata (Spearman's rho = 0.273, P = 0.0106) and mean severity of alopecia tool (SALT) score (P = 0.0130). No significant association was noted between trichoscopic findings and disease activity, family history, disease associations, or nail involvement.
Conclusion: A constellation of trichoscopic findings helps in establishing the diagnosis of alopecia areata obviating the need for biopsy. Copyright:

Introduction

Alopecia areata is a common non-scarring dermatological condition that can affect the scalp and other hair-bearing sites of the body.[1] It is postulated to be a hair-specific autoimmune disease with genetic factors involved in disease susceptibility and severity.[2] Alopecia areata may present as single or multiple patches, ophiasis, alopecia totalis, alopecia universalis, sisaipho, alopecia inversus, or uncommonly as diffuse and reticular patterns. Nail changes such as nail pitting, trachyonychia, longitudinal ridging, and nail thinning may be associated in 10%–66% of cases.[3] A circumscribed area of hair loss with intact follicular ostia devoid of any scarring or atrophy can be clinically diagnosed as a case of alopecia areata. In cases of diagnostic difficulty, confirmation is sought through histopathology, which may be difficult to perform in children and at times are unacceptable to those having facial lesions. However, in recent times, the invasive nature of biopsy has given way to the more popular non-invasive technique of trichoscopy, which allows subtle changes in the skin surface and subsurface to be viewed using its magnifying lenses. Yellow dots, black dots, tapering hair, short vellus hair, and circle hair are some of the consistent findings in alopecia areata.[45678] There is a paucity of literature on trichoscopic features of alopecia areata in Indian patients, especially in the eastern region. In our study, we aimed to elicit the trichoscopic patterns in alopecia areata in East Indian patients and assess their correlation with disease severity.

Materials and Methods

An institution-based observational study was carried out in the department of Dermatology of a tertiary care hospital in eastern India over a period of 18 months. Prior clearance from the institutional ethics committee was obtained, and written informed consent was taken from each study participant. All patients of clinically diagnosed alopecia areata attending the outpatient department during the study period were recruited in the study. Infants, pregnant and lactating mothers, and those not consenting to the study were excluded. Age and sex-matched patients attending the OPD with complaints other than hair disorders were included as controls.

Epidemiological data, clinical and family history, and history of other associated diseases were recorded in a predesigned case record form. Clinical examination including general, systemic and cutaneous examinations was noted in the case record form. Digital photographs of the lesions were taken, and areas of involvement of scalp and body were noted separately. Trichoscopy of alopecic patches was done, photographs were taken, and trichoscopic features were noted down.

Severity of alopecia tool (SALT) score was calculated to assess the severity of scalp involvement.

SALT

The scalp was divided into four parts according to the surface area: vertex: 40% (0.4), right profile of scalp: 18% (0.18), left profile of scalp: 18% (0.18), and posterior aspect of scalp: 24% (0.24)

The percentage of hair loss in each area was multiplied by the percentage surface area of the scalp in that area and was summed up to derive the SALT score.[9]

The scalp hair loss was categorized into S0–S5 grades: S0 - no scalp hair loss but body may involve; S1 - < 25% scalp hair loss; S2 – 26%–50% scalp hair loss; S3 – 51%–75% scalp hair loss; S4 – 76%–99% scalp hair loss; and S5 - total scalp hair loss.

Body involvement was noted in grades B0–B2, where B0 denoted no body hair loss, B1 denoted some body hair loss, and B2 denoted total body hair loss.[9]

After assessing the scalp and body involvement, composite SB grades of severity were calculated from S0B1 to S5B2.

Trichoscopic examination

Trichoscopic examination was performed using the DL1 dermoscope (DermLite, 3 Gen LLC, San Juan Capistrano, CA, USA) (magnification × 10). The dermoscope was attached to a Motorola Moto G5 plus smartphone with an adaptor. Trichoscopic features were observed, and the photographs were taken with the help of the camera of a mobile device.

Statistical analysis

Statistical analysis was done by using software named Statistica version 6 [Tulsa, Oklahoma: StatSoft Inc., 2001). Fisher's exact test and Chi-square test were used to find out the P value, which denotes statistical significance.

Results

In this study, 87 cases and 60 controls attending the dermatology department were included. The mean age for cases was 25.47 ± 14.07 years and that of controls was 26.17 ± 16.38 years, with a male predominance of cases (51; 58.62%). Alopecia in multiple patches (42; 48.27%) was the most common type. Nine cases (13.79%) presented with alopecia universalis, nine cases (10.34%) with ophiasis, three cases (3.45%) with alopecia totalis, and two cases (2.3%) with sisaipho pattern.

Scalp was the most common site of involvement (79; 90.8%). Total body hair loss was seen in 10 cases (11.49%). Nail changes were noted in 48 (54.02%) cases. The hair pull test was found to be positive in 54 cases (62.07%). Disease association was found in 28 cases, with most being associated with hypothyroidism (n = 11), atopy (n = 7), and diabetes mellitus (n = 5).

In our study, yellow dots, black dots, broken hairs, circle hair, and tapering hairs or exclamation hair were significant features in cases with alopecia areata as compared to controls. (P = <0.05) Among the cases, yellow dots were the most common trichoscopic finding (70; 80.46%), followed by black dots (65; 74.71%) and short vellus hairs (61; 70.11%), while broken hairs were the least common trichoscopic feature (7; 8.05%) [Figures 1–4 and Table 1].

Figure 1

Yellow dots (yellow arrow), black dots (black arrow), broken hair (green arrow), exclamation hair (blue arrow) (×10)

Figure 4

Yellow dots (yellow arrow), black dots (black arrow), short vellus hair (orange arrow) (×10)

Table 1

Comparison of trichoscopic features among cases and controls

Trichoscopic features	No. of cases (%)	No. of controls (%)	P*
Yellow dots	70 (80.5)	19 (31.7%)	<0.001
Black dots	65 (74.1)	0 (0.0)	<0.001
Broken hairs	7 (8.1)	0 (0.0)	0.042
Tapering hairs	53 (60.9)	0 (0.0)	<0.001
Short vellus hairs	61 (70.1)	32 (53.3)	0.055
Circle hair	24 (27.6)	6 (10.0)	0.012

*P is from Chi-square test

Circle hair (red arrow) (×10)

Yellow dots (yellow arrow), black dots (black arrow), tapering hair (pink arrow) (×10)

According to the grading for scalp severity, most cases had mild involvement (S1- 49.42% and S2- 17.24%). In eight cases (10.3%), the scalp was not affected (S0).

Statistically significant association was observed between scalp severity calculated according to SALT score and yellow dots (P = 0.0130) [Figure 5]. No association was observed between SALT score and black dots, broken hairs, tapering hairs, and short vellus hairs. However, circle hair was significantly associated with scalp severity grade of alopecia areata (P = 0.009), with none in grade S0 and five cases (55.56%) in grade S5 [Table 2].

Figure 5

Predominant yellow dots in a patient with recurrent episodes alopecia areata (×10)

Table 2

Comparison of trichoscopic features with scalp severity

Trichoscopic features	S0 (n=8) (%)	S1 (n=43) (%)	S2 (n=15) (%)	S3 (n=9) (%)	S4 (n=3) (%)	S5 (n=9) (%)	P*
Yellow dots	6 (75)	32 (74.4)	12 (80.0)	9 (100.0)	3 (100.0)	8 (88.9)	0.484
Black dots	6 (75)	33 (76.7)	12 (80.0)	3 (33.3)	3 (100.0)	8 (88.9)	0.064
Broken hairs	1 (12.5)	2 (4.65)	3 (20.0)	1 (11.1)	0 (0.00)	0 (0.0)	0.423
Tapering hairs	5 (62.5)	23 (53.5)	10 (66.7)	6 (66.7)	3 (100.0)	6 (66.7)	0.640
Short vellus hairs	5 (62.5)	30 (69.8)	10 (66.8)	6 (66.8)	3 (100.0)	7 (77.8)	0.864
Circle hair	0 (0.0)	8 (18.6)	7 (46.7)	2 (22.2)	2 (66.7)	5 (55.6)	0.009

*P is from Chi-square test

When analyzed according to total severity of alopecia areata (S0B1–S5B2), most study participants had grade S1B0 (34; 39.08%), followed by S2B0 (11; 12.64%). Circle hair was associated with total severity of alopecia areata as well (P = 0.041).

No statistically significant association was observed between trichoscopic features and family history of alopecia areata, disease activity (hair pull test), and disease association such as atopy, hypothyroidism, diabetes mellitus, and nail involvement (P > 0.05). However, the hair pull test was found to be associated with the severity of alopecia, with more than 50% noted in lower grades of alopecia areata (P < 0.0001).

Yellow dots were found to have a positive correlation with the number of episodes of alopecia areata (Spearman's rho = 0.273, P = 0.0106) [Table 3].

Table 3

Correlation of trichoscopic features with the number of episodes of alopecia areata

Trichoscopic features	Spearman’s correlation coefficient (rho)	P
Yellow dots	0.273	0.0106
Black dots	0.188	0.0805
Broken hairs	0.0756	0.4863
Tapering hairs	−0.0479	0.6596
Short vellus hairs	−0.0264	0.8050
Circle hair	0.0303	0.7806

Discussion

Alopecia areata is a common cause of non-cicatricial alopecia comprising 0.7% of new dermatology cases in India.[10] The widespread use of trichoscope in different dermatological conditions has given an easy, fast, and non-invasive approach to diagnosis. Thus, trichoscopy is of immense use to differentiate alopecia areata from other nonscarring alopecias, where biopsy is not admissible. We examined 87 cases of alopecia areata with 60 age and sex-matched controls and assessed the trichoscopic findings in each group. Alopecia in single or multiple patches comprised the majority (58; 66.7%) of our study population. This was found to be lesser than that observed by Bapu et al. (87.9%),[11] Guttikonda et al. (84%),[12] and Hegde et al. (73.3%)[13] from South India, but higher than the studies by Inui et al. (46.7%)[14] and Mahmoudi et al. (34.1%).[15] Further, 49.2% of cases had mild severity of scalp involvement with grade S1. This was comparable to the observation by Guttikonda (58%) but more than that by Inui (35%) and Mahmoudi (29.4%).

Trichoscopic findings observed in our study were yellow dots (80.46%), black dots (74.71%), tapering hairs (60.92%), short vellus hairs (70.11%), and circle hair (27.59%). Yellow dots denote distended follicular infundibula filled with sebum and keratin remnants and appear as round or polycyclic yellow to yellow-pink dots, which may sometimes appear white in Indian patients, whereas black dots are the remnant of broken hair shafts inside the follicular ostia. Both yellow dots and black dots were noted in the majority of our study population and were comparable to other studies from India [Table 4].[41112] Presence of yellow dots correlated well with the number of episodes of alopecia areata in our study (P = 0.0106). Yellow dots are observed in plenty and distributed uniformly in hairless patches of alopecia areata, thus being a sensitive marker for the disease. Disease activity as assessed by the hair pull test was found in only 57.1% of those with yellow dots, possibly reflecting the abundance of yellow dots in chronic inactive disease.

Table 4

Comparison of trichoscopic findings of different studies

Trichoscopic findings	Our study	Mane et al.[4]	Bapu et al.[11]	Guttikonda et al.[12]	Hegde et al.[13]	Inui et al.[14]	Mahmoudi et al.[15]	Peter et al.[16]
Yellow dots (%)	80.5	81.8	89.6	88	57.3	63.7	81.8	42
Black dots (%)	74.7	-	78.4	-	84	80.46	48.4	75.0
Broken hair (%)	8.1	-	12.9	56	37.3	45.7	9.5	67
Tapering hair (%)	60.9	19.8	12.1	-	18.6	31.7	30.97	-
Short vellus hair (%)	70.1	-	78.4	66.0	68	72.7	62.7	-
Circle hair (%)	27.6	-	6.9	14.0	-	-	-	17.5

Broken hairs, also observed in trichotillomania, are dystrophic hair shafts or rapid regrowth of partially damaged hairs. However, the lengths of broken hairs tend to be uniform in alopecia areata in contrast to trichotillomania. Our study recorded a much lesser frequency of broken hairs as compared to the previous studies. However, on analysis, a statistically significant association was observed between broken hairs and the type of alopecia areata, with a higher frequency in the patchy or regional patterns (P = 0.0058). Tapering hairs are tapered toward follicles with the proximal end of the hair shaft being narrower than the distal end. Our study recorded a much higher percentage of tapering hairs (60.9%) than previously reported, though no consistent association with disease severity was observed [Table 4]. Short vellus hairs represent thin, non-pigmented hairs having a length of ≤10 mm, and thin, coiled vellus hairs in a circular pattern are called circle hair or pigtail hair.[17] Both are hair regrowth patterns observed in alopecia areata. In a systematic review by Waskiel et al.,[18] the observed frequency of circle hair was in the range of 4%–61%, with a mean value of 21%. This was comparable to our observation (27.6%).

Correlation with disease severity

In our study, yellow dots were present in 74.42% in grade S1 with 100% cases in grades S3 and S4, but the association was statistically non-significant (P = 0.484). This was in keeping with the findings from an Indian study by Guttikonda et al.[12] (P = 0.387). However, yellow dots were positively associated when severity was calculated according to the SALT score (P = 0.0130). Studies from Japan[13] (P = 0.0207) and Iran[14] (P < 0.001) also concluded yellow dots to be positively related with scalp severity.

Black dots were present in nearly three-fourth of our study population; however, no association was observed with disease activity and severity (P = 0.908). This was similar to findings by Mahmoudi et al.[15] (P = 0.994) and Guttikonda et al.[12] (P = 0.871).

Inui et al. observed broken hairs to be associated with disease activity and observed them even in cases responding to treatment.[14] They also noted broken hairs, black dots, and tapering hairs to be specific for alopecia areata. In our study, broken hairs were associated more with patchy alopecia (P = 0.005).

Circle hair was observed to be significantly associated with total severity of alopecia areata (P = 0.002) and hence with higher grades of alopecia (P = 0.035). These hairs are commonly observed in childhood alopecia areata,[19] probably indicating more proliferative hair regrowth in the pediatric population. In our study population, 56% of those with circle hair were within the second decade of their lives, though no significant association was noted between age groups and circle hair (P = 0.139).

Correlation with disease activity

There was no significant association between disease activity and trichoscopic findings. However, the hair pull test was found to be significantly associated with the severity of alopecia with a higher proportion in patchy alopecia. This was probably due to lack of hair in the more severe types (universalis and totalis) and the higher representation of alopecia areata with mild severity in our study population.

A small sample size may be a limitation of this study.

Conclusion

Dermoscope is a valuable tool for diagnosing alopecia areata. Though no single feature is specific to alopecia areata, a constellation of these findings together can establish the diagnosis in doubtful cases, which otherwise necessitated histopathological examination. Tapering hairs and circle hair were found in higher frequency than previous studies. Yellow dots and circle hair were associated with the severity of scalp alopecia areata. Thus, trichoscopy is valuable not only to diagnose but also to correlate the severity of alopecia areata. Further studies with a larger study population need to be undertaken to find out the specificity of trichoscopic features of alopecia and their correlation with severity of disease and also with other hair disorders.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.