
==== Front
Indian J Dermatol
Indian J Dermatol
IJD
Indian J Dermatol
Indian Journal of Dermatology
0019-5154
1998-3611
Wolters Kluwer - Medknow India

IJD-69-285
10.4103/ijd.ijd_346_23
Original Article
Comparative Study of Trichoscopic Features of Alopecia Areata between Adults and Children and between Different Body Parts (Scalp, Beard, Eyebrow, and Moustache)
Raheem Aula
Al-Dhalimi Muhsin 1
From the Fellow of the Iraqi Commission for Medical Specializations (FICMS)/Dermatology and Venereology, University of Jabir Ibn Hayyan College of Medicine, Imad Sikr, Najaf, Iraq
1 Dermatology and Venereology, Faculty of Medicine, University of Kufa, Kufa, Najaf Governorate, Iraq
Address for correspondence: Dr. Aula Raheem, Fellow of the Iraqi Commission for Medical Specializations (FICMS)/Dermatology and Venereology, University of Jabir Ibn Hayyan College of Medicine, Imad Sikr B21 N5, Najaf, Iraq. E-mail: ular2020@gmail.com
Jul-Aug 2024
19 8 2024
69 4 285291
4 2023
4 2024
Copyright: © 2024 Indian Journal of Dermatology
2024
https://creativecommons.org/licenses/by-nc-sa/4.0/ This is an open access journal, and articles are distributed under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike 4.0 License, which allows others to remix, tweak, and build upon the work non-commercially, as long as appropriate credit is given and the new creations are licensed under the identical terms.
Background:

Round patches of baldness on the scalp or entire body are typically caused by the common, non-scarring hair loss condition known as alopecia areata (AA). Follicular units with two to four terminal hairs and one or two vellus hairs can be seen on a healthy, typical scalp trichoscopy.

Aim of the Study:

To compare trichoscopic features between adults and children and between different body parts.

Patients and Methods:

A cross-sectional observational study was performed on 90 patients; AA of the scalp and other body parts attended the dermatology out-patient clinic. A Gen Dermlite D100 Dermoscope was used to examine AA lesions and compare their features according to age and different body parts.

Results:

Scalp was the most common area among all patients, 65.6% (among adults, it was 50%, and among children, it was 85%), with a significant difference, P = 0.001. The most common trichoscopic feature among all patients was empty follicular opening in 74 (82.2%) lesions; among children, it was honeycomb pigment in 35 (87.5%) lesions, while among adults, it was empty follicular opening in 40 (80%) lesions. Tulip hair was significantly higher among adults, P = 0.036. At the same time, honeycomb pigment patterns and pohlpinkus constriction were significantly higher among children, P = 0.044 and P < 0.001, respectively.

Conclusion:

The most common trichoscopic feature of adult lesions was empty follicular opening, while honeycomb pigment was dominant among children. Tulip hair was higher among adults, while honeycomb pigment patterns and pohlpinkus constriction were higher among children.

KEY WORDS:

Alopecia areata
adults
children
trichoscopic
==== Body
pmcIntroduction

Alopecia areata (AA) is an autoimmune-mediated T-cell attack on hair follicles, resulting in patchy hair loss and an unsightly appearance. With a prevalence rate of up to 2%, the lifetime risk of developing AA is 2%.[1] Historically, younger age groups have had a higher prevalence of A.[1] AA is a common cause of non-scarring hair loss that generally causes round patches of baldness on the scalp or entire body. In some patients, however, AA is characterized by a diffuse hair loss commonly misdiagnosed as telogen effluvium or androgenetic alopecia.[23]

For dermoscopy of the hair and scalp, Lidia Rudnicka and Malgorzata Olszewska introduced the term “Trichoscopy” in 2006. A manual dermoscopy with a 10x magnification or a video dermoscopy with 20x to 1000x magnification can be employed for scalp examination. The follicular unit in a healthy scalp has one or two vellus hairs and two to four terminal hairs inside.[456]

On a healthy, normal scalp trichoscopy, follicular units with two to four terminal hairs and one or two vellus hairs can be seen. Darker skin has a noticeable brown homogeneous honeycomb pigment network across the scalp, emphasising places exposed to the sun.[7]

The trichoscopic diagnosis should be based on the coexistence of several trichoscopy findings rather than a single feature. The trichoscopic features may not be affected by the type or severity of the disease.[7]

A few studies have been done on Iraqi individuals with Alopecia areata regarding comparing the trends of trichoscopic features in adults and children. Furthermore, there have been a few epidemiological research studies on AA globally, and no definitive findings have been made. To fill in those knowledge gaps, there is a need for worldwide research partnerships that employ standardised methodologies.

Our manuscript focussed on identifying the primary disparity in dermoscopic characteristics between adults and children due to variations in scalp anatomy. It aimed to determine if there is a distinction between AA on the scalp and other parts of the body. This will provide further insights into the natural progression of the disease in different regions and whether treatment options vary as well.

Methods

This cross-sectional observational study was performed at Al Sadr Medical City/Dermatology Outpatient Clinic in Al Najaf City from 1 August 2020 to 30 October 2021. Ethical approvals were obtained from the concerned committees. Verbal consent was obtained from patients before participation and before the researcher filled out the questionnaire. Data collection will be kept confidential and not divulged except for the study purpose.

This study included ninety (90) patients, with AA of the scalp and other different body parts who attended a Dermatology Outpatient Clinic. Fifty patients were adults, aged 18–44 years, and 40 were children, aged 3–17.

Those previously receiving systemic or topical medication for the present phase were excluded from the study. The inclusion criteria were all patients with AA.

All patients underwent a thorough medical history review, physical examination, photography of any abnormalities causing patchy hair loss, and trichoscopic inspection. AA lesions were examined with a Gen Dermlite D100 Dermoscope to compare their characteristics across age groups and body regions. The technique employed was convenience sampling.

A structured questionnaire was used by the researcher for data collection for 12 months. The questionnaire included demographic features such as age, sex, and disease duration; the lesion sites included the scalp, beard, eyebrow, and moustache. There is past medical history such as DM, asthma, atopic dermatitis, thyroid disease, previous history of AA, and family history of AA. There are trichoscopic features such as yellow dot, empty follicular opening, black dot, triangular hair, broken hair, short villus hair, upright regrowing hair, pigtail hair, pohlpinkus constriction, perihilar sign, blotchy erythema, hem-like pigment pattern, vascular network, honeycomb pigment pattern, coudability sign, i-hair, perifollicular haemorrhage, tulip hair, white hair, flame hair.

Clinical and trichoscopic photographs of the lesions were performed with a polarized light non-contact dermoscope (3 Gen Dermlite DL 100) at ten folds magnification. The dermoscopic properties are diode light technology with long life lithium power. It is a lightweight design (3.5 oz/99 g), with the removal of the glass plate for better visualization of vascular structures and pictured with an iPhone 8 plus.

The examination method was after the patient was sitting; the dermoscope was held with the left hand and the cell phone with the right hand, and then several pictures were taken at the centre of the lesion and the periphery of it.

A pilot study was carried out on a few cases to assess the applicability of the questionnaire and the time needed, in addition to identifying any obstacles or difficulties the researcher may face while filling out the questionnaire. Those cases in the pilot study were excluded from the main study.

Microsoft Excel 2010 was used for data entry. The SPSS-24 program was used for analysing data. Chi-square or Fisher’s exact test were used for categorical variables, while an independent student t-test was used for numerical data. Data were represented by frequencies and percentages using tables and figures. Significances of variables were considered when the P value was < 0.05.

Results

This study included 90 patients with AA. Forty (44.4%) patients were children (3–17 years) with a mean age of 8.90 ± 3.761 years, and 50 (55.6%) patients were adults (18–44 years) with a mean age of 27.80 ± 7.409 years. The mean disease duration among children was 26.45 ± 27.804 days, while that of adults was 30.42 ± 48.913 days with no significant difference, P = 0.83.

Out of the total, there were 51 (56.7%) males; of them, 23 (45.1%) were children, 28 (54.9%) were adults, and 39 (43.3%) were females; of them, 17 (43.6%) were children and 22 (56.4%) were adults, with no significant difference, P = 0.99.

Sixty (66.7%) patients had recurrent attacks, 22 (24.4%) patients with a positive family history of AA, 10 (11.11%) patients with DM, 7 (7.8%) patients with thyroid disease, and another 7 (7.8%) patients with atopic dermatitis.

History of recurrence was more common among adults with a significant difference compared to children, P < 0.001. No significant difference between adults and children was found among gender or family history, P > 0.05.

Of the total lesions (152), only 98 were examined using a trichoscope. Patients presented with lesions of different numbers and sites. Only one lesion from each site was examined if there were multiple lesions in the same site for the same patient. Lesions are distributed over four body parts (scalp, beard, eyebrow, and moustache), as shown in Table 1.

Table 1 Distribution of lesions according to the site

Site	All Lesions	No. of examined lesions by trichoscope	
		
n	%	n	%	
Scalp	100	65.79	59	60.20	
Beard	21	13.82	13	13.27	
Eyebrow	25	16.45	20	20.41	
Moustache	6	3.95	6	6.12	
Total	152	100	98	100	

The most common trichoscopic features were empty follicular opening in 74 (82.2%) lesions, honeycomb pigment patterns in 69 (76.7%) lesions, yellow dots in 63 (70.0%) lesions, vascular network in 59 (65.6%) lesions, and broken hair in 51 (56.7%) lesions as shown in Table 2.

Table 2 Distribution of patients according to the trichoscopic features of 98 lesions

Trichoscopic features	Groups	n	P	
	
Children	Adults	
		
n	%	n	%	
Yellow dot	26	65.0%	37	74%	63	0.37	
Empty follicular opening	34	85.0%	40	80%	74	0.6	
Black dot	15	37.5%	27	54%	42	0.14	
Triangular hair	13	32.5%	19	38%	32	0.66	
Exclamation mark hair	19	47.5%	24	48%	43	0.1	
Tapered hair	19	47.5%	22	44%	41	0.83	
Broken hair	25	62.5%	26	52%	51	0.4	
Short villus hair	11	27.5%	15	30%	26	0.8	
Upright regrowing hair	10	25.0%	13	26%	23	1	
Pigtail hair	10	25.0%	6	12%	16	0.15	
Pohlpinkus constriction	20	50.0%	2	4%	22	<0.001	
Peripilar sign	21	52.5%	19	38%	40	0.203	
Blotchy erythema	19	47.5%	24	48%	43	1	
Hem-like pigment pattern	8	20.0%	15	30%	23	0.34	
Vascular network	23	57.5%	36	72%	59	0.18	
Honeycomb pigment pattern	35	87.5%	34	68%	69	0.044	
Coudability sign	10	25.0%	18	36%	28	0.36	
i-Hair	5	12.5%	15	30%	20	0.07	
Perifollicular haemorrhage	0	0.0%	5	10%	5	0.06	
Tulip hair	4	10.0%	15	30%	19	0.036	
White hair	4	10.0%	9	18%	13	0.37	
Total	43	43.9%	55	56.1%	98		

The most common trichoscopic features among children were honeycomb pigment in 35 (87.5%) lesions, empty follicular opening in 34 (85.0%) lesions, yellow dots in 26 (65%) lesions, broken hair in 25 (62.5%) lesions, and vascular network in 23 (57.5%) lesions as shown in Table 2 and Figure 1.

Figure 1 (a) 7 years child with AA (b) Trichoscopic features of children green circle are around empty follicular opening, blue circle broken hair, red arrow points pigment network, and the blue arrow points to black dots

The most common trichoscopic features among adults were empty follicular opening in 40 (80%) lesions, yellow dots in 37 (74%) lesions, vascular network in 36 (72%) lesions, honeycomb pigment in 34 (68%) lesions, and black dots in 27 (54%) lesions as shown in Table 2 and Figure 2.

Figure 2 (a) Clinical picture of AA; (b) Trichoscopic feature in adult red circle yellow dot, green circle vascular network, green arrow empty follicular opening

Tulip hair was significantly higher among adults, P = 0.036. At the same time, the honeycomb pigment pattern and Pohlpinkus constriction were significantly higher among children, P = 0.044 and P < 0.001, respectively, as shown in Table 2.

Examination of scalp lesions using a trichoscope revealed that the most common features were empty follicular opening in 52 (88.1%) lesions, honeycomb pigment pattern in 45 (76.3%) lesions, yellow dots in 39 (66.1%) lesions, broken hair in 32 (54.2%) lesions, and peripilar sign in 31 (52.5%) lesions, as in Table 3 and Figure 3.

Table 3 Trichoscopic features according to the sites of 98 lesions

Trichoscopic features	Scalp	Beard	Eyebrow	Mustache	
				
n	%	n	%	n	%	n	%	
Yellow dot	39	66.1%	10	76.9%	10	50.00%	4	66.70%	
Empty follicular opening	52	88.10%	8	61.50%	14	70.00%	5	83.30%	
Black dot	25	42.40%	9	69.20%	9	45.00%	2	33.30%	
Triangular hair	22	37.30%	3	23.10%	9	45.00%	3	50.00%	
Exclamation mark hair	26	44.10%	7	53.80%	15	75.00%	2	33.30%	
Tapered hair	23	39.00%	8	61.50%	12	60.00%	2	33.30%	
Broken hair	32	54.20%	8	61.50%	13	65.00%	3	50.00%	
Short villus hair	18	30.50%	4	30.80%	5	25.00%	1	16.70%	
Upright regrowing hair	16	27.10%	5	38.50%	5	25.00%	1	16.70%	
Pigtail hair	15	25.40%	1	7.70%	0	0.00%	0	0.00%	
Pohlpinkus constriction	16	27.10%	0	0.00%	6	30.00%	0	0.00%	
Peripilar sign	31	52.50%	3	23.10%	3	15.00%	3	50.00%	
Blotchy erythema	27	45.80%	7	53.80%	12	60.00%	2	33.30%	
Hem-like pigment pattern	16	27.10%	4	30.80%	4	20.00%	0	0.00%	
Vascular network	31	52.50%	12	92.30%	15	75.00%	5	83.30%	
Honeycomb pigment pattern	45	76.30%	10	76.90%	17	85.00%	4	66.70%	
Coudability sign	17	28.80%	4	30.80%	5	25.00%	3	50.00%	
i-Hair	3	5.10%	9	69.20%	6	30.00%	3	50.00%	
Perifollicular haemorrhage	0	0.00%	3	23.10%	2	10.00%	2	33.30%	
Tulip hair	4	6.80%	8	61.50%	6	30.00%	3	50.00%	
White hair	4	6.80%	5	38.50%	4	20.00%	1	16.70%	
Total	59	65.60%	13	14.40%	20	22.20%	6	6.70%	

Figure 3 (a) Solitary scalp lesion in adult male; (b) Trichoscopic feature of AA on the scalp blue rectangle is empty follicular opening, the blue arrow is a yellow dot, a green circle is a peripilar sign and broken hair

Beard lesions revealed the features: vascular network in 12 (92.3%) lesions, honeycomb pigment pattern in 10 (76.9%) lesions, yellow dots in 10 (76.9%) lesions, i-Hair in 9 (69.2%) lesions, and black dots in 9 (69.2%) lesions as in Table 3 and Figure 4.

Figure 4 (a) Single patch of AA on beard area of one-month duration (b) Trichoscopic feature of AA of beard area black circle represents hair, green circle represents a black dot, the blue circle is honeycomb pigment network, and the green arrow represents the preservation of white

Eyebrow features were honeycomb pigment pattern in 17 (85%) lesions, exclamation in 15 (75%) lesions, vascular network in 15 (75%) lesions, empty follicular opening in 14 (70%) lesions, and black dots in 13 (65%) lesions as in Table 3 and Figure 5.

Figure 5 (a) represent eyebrow lesion in 18 years old male; (b) Trichoscopic feature of AA of the green circle and blue arrow represents a vascular network with a honeycomb pigment network; the green arrow represents short villus hair

The most common trichoscopic features at moustache were empty follicular opening in 5 (83.3%) lesions, vascular network in 5 (83.3%) lesions, honeycomb pigment pattern in 4 (66.7%) lesions, yellow dots in 4 (66.7%) lesions, and broken hair in 3 (50%) lesions as in Table 3 and Figure 6.

Figure 6 (a) AA of the moustache; (b) Trichoscopic features in which the blue circle represents a yellow dot, the green arrow represents exclamation mark hair, and a green circle is a caudability sign with a honeycomb pigment network

Discussion

AA can occur at any age, and the lifetime incidence is increased at a linear rate. The median age at diagnosis is usually 33 years in adults, as reported by many studies. Male patients are more likely to be detected in childhood. At the same time, females are more likely to present in adolescence and have significant concomitant nail involvement or other autoimmune diseases, which differs from our findings.[89]

Further research, however, found that the average age of onset varied and appeared to fall between 25 and 36 years old. Children with early-onset AA between the ages of 5 and 10 typically present without any obvious sex difference. Some other large epidemiological studies indicate a slight female-to-male gender bias, but this could be explained due to higher female concern and interest regarding hair status and subsequent treatment.[91011]

Regarding disease comorbidities, the study revealed that most patients had recurrent attacks, about one-fourth of them gave a positive family history of AA, and less common comorbid diseases were DM, thyroid disease, and atopic dermatitis. History of recurrence was more common among adults with a significant difference compared to children, but no significant difference was found among gender or family history. Comorbidities can provide essential etiologic insights, suggesting the possible disease mechanisms that link clinical entities with each other and may provide a classification scheme for included patients. It is unknown what specific event causes and results in AA. There have been some recorded triggers, most frequently physical or mental stress, immunizations, illnesses, and medications.[12]

One of the first large-scale studies performed by Lim et al. in 2018 to examine the co-distribution of 161 ICD (international classification of diseases) codes, including AA, among 1.5 million adult patient records, the study found enrichment, and comorbidities of 34 diseases among patients with AA, including not only immune-related pathologies but also different neuropsychiatric disorders like epilepsy, migraines, attention deficit, depression, and bipolar disorders. Metabolic conditions were also reported, including type 2 diabetes and problems with lipid metabolism. Then, several large publicly available data sources were further used to investigate disease comorbidities in AA, discovering solid evidence for comorbidities involving immune system pathologies like thyroid disorders and different additional neuropsychiatric and metabolic disorders.[11]

Kakourou et al.[12] study findings in the pediatric population, which evaluate AA’s clinical and epidemiological profiles in children. The comorbid events found in affected children were a history of a stressful event, personal history of autoimmune disease, a family history of autoimmune disease other than thyroiditis, and personal history of atopy; the severity of AA was associated with the early age onset of the disease.

A retrospective study used chart review by Rangu et al.[13] in 2019 on pediatric patients in Philadelphia and reported that less than half of the children 41% had concomitant atopic dermatitis, 28% had a family member diagnosed with AA, and 27% of them had a first-degree family member showed a history with one or more autoimmune diseases.

In AA black dots, micro-exclamation hairs and tapered broken hairs indicate and correlate with disease activity, while yellow dots and vellus hairs usually correlate with disease severity.[14]

Inui et al. noted that empty follicles could offer helpful prognostic information (signalling the non-destructive character of AA). Empty follicular openings and honeycomb pigment patterns were found in the majority of AA cases in the current study under trichoscopic examination; this finding was also found in other studies by Mane et al. as they were seen as brand-new, non-pigmented openings within the patch, which may or may not be clinically detectable.[1516]

At the same time, people with darker skin tones typically have more noticeable honeycomb pigment. Bald and sparsely haired areas displayed a darker pigment network that resembles sunburn from overexposure to the sun. A grid and holes characterise this patchwork design. The holes stand in for the hypochromic suprapapillary epidermis, whereas the lines represent the melanotic rete ridges.[6]

Several research, including ours, have found that yellow dots are a sensitive marker for assessing and detecting AA because they are more prevalent in this condition. Similar to another study by Ekiz et al., 70% of our patients’ cases included yellow spots. Nonetheless, certain research BY Karadag et al. indicated a lower incidence. This discrepancy in findings between our study and other studies can be credited to differences in skin types (yellowish skin and darker skin types may make it difficult to see the yellow dots on dermoscopy), various cleaning and shampooing behaviours, and the different types of dermoscopy used in the examination.[1718]

Black dots are hard to understand in Caucasians because of their hair colour. On the other hand, black dots (cadaverous hairs) are the remnants of telo hair. In our study, black dots were seen in 47% of the cases, and the outcome was similar to that of Karadag Köse and Güleç and Mane et al.[1518]

Exclamation mark hair was found in 47.5% of the AA cases in the current investigation under trichoscopic inspection; this finding was also highlighted in a comparable percentage by Ekiz et al. In most cases, the name “tapering hair” is preferable to “exclamation mark hair” because the afflicted hair is not shaped like an exclamatory mark in the traditional sense. It is caused by the hair shafts narrowing as they approach the follicles, which is more easily seen through trichoscopy than by the naked eye. It becomes more sensitive and diagnostic when accompanied by yellow spots, short vellus hairs, and/or hairs that grow in pigtails. While it is frequently observed in active AA around the periphery of the lesions, tapering hair is also thought to indicate active AA. According to Inui et al., broken hairs are regarded as clinical indicators of the severity and activity of AA disease.[1617]

Also, this is agreed with the latter Indian study on adult patients by Guttikonda et al., which demonstrated various dermoscopic patterns in the lesions like yellow dots in 88% of patients, short vellus hair in 66%, black dots in 58%, broken hairs in 56%, tapering hair in 26%, pigtail hair in 14%, Coudability hairs in 14%, and Pohl-Pinkus constrictions in the last 2% of them.[19]

In comparison to the pediatric population, a study used trichoscopy as a non-invasive instrument for a rapid finding of AA in paediatric patients; the study included a sample of children with AA done in Cairo Hospital, 2014; the most trichoscopic precise structures were yellow dots, short vellus hairs, and exclamation mark, respectively, which is different from our findings.[20]

Triangular hairs are new trichoscopic findings presented of AA. Similarly, the most common trichoscopic results of AA reported by Waśkiel-Burnatin in 2019 in children are short vellus hairs and empty follicular openings. Also, pigtail hairs and empty follicular openings were more commonly presented in children than adults in the same study. In contrast, yellow dots were less commonly revealed in children than in adults.[21]

The current study reported that the most common features of scalp lesions using a trichoscope were empty follicular openings, vascular networks in beard lesions, and honeycomb pigment patterns in eyebrow features. At the same time, the most common trichoscopic features at the moustache were empty follicular openings.

The aforementioned discovery was also made by Inui et al.,[16] who discovered that empty follicles were primarily found in the scalp and moustache and that cadaveric hairs, empty follicles, broken hairs, exclamation mark hairs, and yellow dots could be used to thoughtfully detect many AA cases that were challenging to diagnose clinically. However, it demonstrated that exclamation mark hair, yellow spots, and short vellus hair are distinctive signs of AA, particularly in the beard region and eyebrows. Additional clinical and histological testing would be necessary if these signs were missed during trichoscopy.

Inui et al. report was inconsistent with Waśkiel et al., who presented in a systemic review the spectrum of trichoscopic findings in patients with AA in 2018. They stated that there is no pathognomonic trichoscopic marker for AA, and at the same time, the most common and usual trichoscopic features are not the most specific. Therefore, the diagnosis should be based mainly on the findings of several trichoscopic features and not on the presence of one feature. A rarely reported feature was demonstrated in this review, which includes upright regrowing hairs, pigtail (circle) hairs, and Pohl-Pinkus’s constrictions in adult patients; those manifestations were helpful in the diagnosis of AA.[162122]

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.
==== Refs
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