Trichoscopy of Dark Scalp

Dermatology in black skin

The vast majority of publications in dermatology refer to lightly pigmented skin, with few addressing the peculiarities of black skin. In addition there is no consensus on what it means to be black in different regions of the world. The lack of knowledge on the subject makes it difficult to recognize and manage dermatoses in this type of skin. This article aims to review the literature on intrinsic characteristics, as well as epidemiological and clinical aspects of the cutaneous manifestations of different dermatoses in black skin. It was found that there are sometimes striking differences, in the structural, biological, and functional aspects when comparing lightly pigmented and black skin. There are also physiological changes that need to be recognized to avoid unnecessary interventions. Some dermatoses have a higher incidence in black skin, such as acne, eczema, dyschromia and dermatophytosis. On the other hand, several dermatoses are more specific to black skin, such as pseudofolliculitis barbae, keloid, dermatosis papulosa nigra, ulcers caused by sickle-cell anemia, dactylolysis spontanea, confluent and reticulated papillomatosis of Gougerot and Carteaud, and some diseases of the hair and scalp (including fragile and brittle hair, traction alopecia, folliculitis keloidalis nuchae, folliculitis dissecans and central centrifugal cicatricial alopecia). A spectrum of peculiar aspects of specific dermatoses, including sarcoidosis, lichen planus (with emphasis on the pigmentosus variant), psoriasis, lupus erythematosus, vitiligo, syphilis, pityriasis versicolor, and neoplasms are highlighted. In the latter, characteristics of basal cell carcinoma, squamous cell carcinoma, and melanoma are compared, in addition to highlighting unusual aspects of primary cutaneous T-cell lymphoma, endemic Kaposi sarcoma, and dermatofibrosarcoma protuberans.

Updates on disorders in curly hair

Hair disorders, including central centrifugal cicatricial alopecia (CCCA), traction alopecia (TA), and acquired trichorrhexis nodosa (ATN), commonly occur in individuals with curly textured hair. Curly textured hair in individuals of African descent has unique properties and can present diagnostic and therapeutic challenges. CCCA has been linked to uterine leiomyoma and type 2 diabetes mellitus, as well as fibroproliferation. TA often presents with a fringe sign and can arise from high-tension hairstyles presumed to be protective. Trichoscopy is useful in establishing a diagnosis; perifollicular halos are more commonly seen than perifollicular erythema or scale in CCCA. In TA, miniaturized follicles, hair casts, and "flambeau sign" can be seen. Hairstyling practices likely contribute to TA and ATN; however, the data are mixed on the role of chemical relaxers and heat styling in CCCA. Unique considerations in the presentation of frontal fibrosing alopecia in curly textured hair have also been published recently. This review provides a comprehensive, up-to-date summary of these disorders with an emphasis on their unique properties, as well as considerations in hair care for curly textured hair.

Non-scarring alopecia in systemic lupus erythematosus patients at the Lagos State University Teaching Hospital: a cross-sectional study of prevalence, pattern, trichoscopy features and histopathological analysis

Introduction

trichoscopic and histopathological evaluation of non-scarring systemic lupus erythematosus (SLE) alopecia is uncommon. We aimed to document the prevalence, pattern of hair loss, trichoscopic and histopathologic differences between systemic lupus erythematosus patients with and without hair loss.

Methods

this was a cross-sectional comparative study of 75 systemic lupus erythematosus patients, 36 with hair loss from February to December 2020. Trichoscopic evaluation was conducted on all 75 patients. Twenty-three patients (12 with hair loss and 11 without) had scalp biopsies with mucin deposit evaluation. Disease activity was documented using the SLE disease activity index. Data was analyzed using SPSS 22.

Results

the mean age of the patients was 33.7 ± 12.4 years. Non-scarring alopecia was observed in 48%. The pattern of hair loss was <4 patches in 44.4%, mild diffuse in 25%, and severe diffuse in 30.6%. Disease activity was mild in 38.9%. Hair shaft changes included thin hair (97.2%), decreased number of hairs per follicular unit (97.2%), hypopigmented hair (85.7%), and follicular red dots (27.8%). Significant differences between the two groups were; a reduction in size and number of sebaceous glands on histopathology, hair shaft, and scalp pigmentary changes in the hair loss group.

Conclusion

the prevalence of non-scaring alopecia is high in SLE patients with patchy type as the commonest pattern. Trichoscopic and histopathologic differences exist in SLE patients with and without hair loss and the normal-appearing scalp in SLE patients is involved in the inflammatory process. Hair shaft thinning, hypopigmentation, and scalp pigmentary changes occur in SLE.

A Cross-Sectional Study on Post-Coronavirus Disease (COVID-19) Hair Loss at a Tertiary Care Hospital

INTRODUCTION

Severe acute respiratory virus syndrome coronavirus 2 (SARS-CoV-2) was responsible for coronavirus disease (COVID-19) pandemic. As patients recovered from COVID-19 infection, hair loss was increasingly observed as a distressing symptom.

METHODS

This was a cross-sectional study of patients with post COVID-19 hair loss between July to December 2021 at a tertiary care center. Detailed history, clinical examination, trichoscopy and biochemical tests were performed and recorded. COVID-19 disease severity was assessed based on duration of COVID-19 infection and place of management.

RESULTS

The study included 120 patients with a mean age of 39.6 years. The majority of the patients were females treated at home and had COVID-19 infection for >2 weeks. The mean visual analog scale (VAS) score for stress was 5.25. Vitamin D deficiency was present in 56.7% and low ferritin in 30% of cases. The mean time of onset of hair loss post COVID-19 was 49 days. Patients mainly presented with diffuse hair loss. Trichodynia was present in 15.8% of cases. The degree of hair loss was severe in 55.8% of the subjects. Positive hair pull test was seen in 65% of patients. Most common trichoscopic features included single hair follicles (81.7%) and vellus hair >10% (60%).

CONCLUSIONS

The mean time of onset of hair loss post COVID-19 infection was less than 2 months. Majority patients had diffuse pattern and severe degree of hair loss. Trichoscopy can aid in unmasking co-existing patterned hair loss in patients presenting clinically with diffuse hair loss.

Dermoscopy of Hair and Scalp Disorders (Trichoscopy) in Skin of Color - A Systematic Review by the International Dermoscopy Society "Imaging in Skin of Color" Task Force

Hair and scalp disorders are of significant interest for physicians dealing with dark phototypes due to their prevalence and potential aesthetic impact resulting from a higher tendency for scarring. In order to facilitate their non-invasive diagnosis, several dermoscopic studies have been published, yet data are sparse and no systematic analysis of the literature has been performed so far. This systematic literature review summarizes published data on trichoscopy of hair and scalp diseases (trichoscopic findings, used setting, pathological correlation, and level of evidence of studies). A total of 60 papers addressing 19 different disorders (eight non-cicatricial alopecias, nine cicatricial alopecias, and two hair shaft disorders) were assessed, for a total of 2636 instances. They included one cross-sectional analysis, 20 case-control studies, 25 case-series, and 14 single case-reports, so the level of evidence was V and IV in 65% and 33% of cases, respectively, with only one study showing a level of evidence of III. Notably, although there is a considerable body of literature on trichoscopy of hair/scalp diseases, our review underlined that potentially significant variables (e.g., disease stage or hair texture) are often not taken into account in published analyses, with possible biases on trichoscopic patterns, especially when it comes to hair shaft changes. Further analyses considering all such issues are therefore needed.

Scarring Alopecia

African hair shaft and pigmented scalp have unique features that challenge diagnosis in scarring alopecia. In addition, Black patients may associate 2 or more types of hair disorders. Therefore, it is imperative to understand their findings thoroughly to establish a good diagnosis. Differential diagnosis on the frontal scalp includes traction alopecia and frontal fibrosing alopecia. Disorders such as central centrifugal cicatricial alopecia, fibrosing alopecia in a pattern distribution, discoid lupus erythematosus, and lichen planopilaris usually affect the middle scalp. Folliculitis decalvans, dissecting cellulitis, and acne keloidalis nuchae are the main differential diagnosis of the posterior scalp.

Non-Invasive Techniques for Evaluating Alopecia Areata

Alopecia areata (AA) is a disease affecting mostly young patients, being the second most prevalent cause of alopecia. For the assessment of AA patients, numerous non-invasive techniques are available. For diagnosing and treating AA, non-invasive hair follicle exploration is crucial. Trichoscopy, videodermoscopy, pull test, global scalp photography and scalp imaging techniques (reflectance confocal microscopy (RCM), multiphoton microscopy (MPM), and high-frequency ultrasonography (HF-USG) are non-invasive methods used to assess the hair loss. Short vellus hairs and yellow dots were the most commonly reported and sensitive trichoscopy signs of AA. Additionally, it was observed that AA activity was associated with black dots, micro-exclamation mark hairs and tapering hairs. A good prognosis of AA includes the transformation of vellus into terminal hairs. Reflectance confocal microscopy is a non-invasive imaging technique for in vivo evaluation of the skin and observation of cell morphology with a nearly histological resolution, which is helpful in diagnosis and management of AA. Additionally, MPM delivers information on hair follicles and scalp inflammation and can be utilized to assess hair growth while undergoing treatment. High-frequency ultrasonography allows distinguishing between hair cycle phases, which is undoubtedly important from the prognostic of AA. The current review aims to discuss the non-invasive methods of diagnosis of AA.

Trichoscopic features of hair and scalp in noncomplaining individuals: A descriptive study

BACKGROUND

Trichoscopy is a simple noninvasive tool that is used in calculating different hair parameters and the diagnosis of different hair/scalp diseases at variable magnifications.

OBJECTIVE

The aim of this work is to describe the features and parameters of hair and scalp in a healthy sample of Egyptian population using videodermoscopy. This may help to provide standard range of measurements of normal hair in both males and females.

METHODS

A nonrandomized, observational study for features and parameters of hair structure, performed on 368 healthy Egyptian subjects with no hair/scalp complaint.

RESULTS

Each scalp area has its own vascular pattern. Male subjects showed different values regarding their hair parameters from the female subjects. No significant difference was seen after application of hair dye, except for few values. In both genders, there was a change in hair parameters with age. Smoking had a negative influence on hair parameters.

CONCLUSION

Hair features and parameters observed in our population are different from those reported by other populations. Smoking affects hair thickness and density. Dyed hair has greater thickness mostly due to the protective effect of hair conditioners.

Primary cicatricial alopecia: Recent advances in evaluation and diagnosis based on trichoscopic and histopathological observation, including overlapping and specific features

Primary cicatricial alopecia (PCA) is a form of alopecia in which inflammatory cells target follicles, including the bulge region containing follicular stem cells, leading to permanent alopecia. New classifications of PCA subtypes have recently been proposed, including those that account for novel trichoscopic and histopathological features of PCA, enabling greater precision in the evaluation and diagnosis of this condition. Nonetheless, diagnosis remains challenging clinically and histopathologically because the etiology of PCA is multifactorial. Inconsistent use of terminology, overlapping disease concepts, and changes in the clinical or histopathological severity of inflammation in the disease course in the same patient also make diagnosis quite challenging. The present study comprehensively reviews recent progress in diagnostic techniques, including the use of clinical, trichoscopic, and histopathological features, in evaluating each PCA subtype, containing overlapping and specific features. Elucidating the features of PCA, including those that are common to multiple subtypes as well as specific to each in both early and advanced-stage lesions, is important for accurate diagnosis. Improving the evaluation and treatment of this disease depends on having a broader clinical understanding that takes into account not only the features of the disease at a given point in time, but also the changes that occur during the entire disease course.

Update on trichoscopy: Integration of the terminology by systematic approach and a proposal of a diagnostic flowchart

Trichoscopy represents a non-invasive diagnostic modality widely used in daily practice. Despite the common perception that this technique has been fairly established, some key issues remain to be addressed. Complexity and inconsistency in terminology in past literature are likely to confuse investigators when they are recording, reporting, and retrieving the findings. In addition, a diagnostic algorithm adopting sufficiently integrated and updated findings is not readily available. By adopting a systematic review approach, this review attempted to redefine major trichoscopic findings and integrate their synonyms individually into the most frequently used terms besides identifying and discussing terms which potentially cause confusion. The findings are categorized into five subgroups: hair shaft, follicular, perifollicular, scalp findings, and hair distribution pattern abnormalities. The calculation of sensitivities and positive predictive values of such redefined findings was conducted by reviewing the descriptions in the past literature on major hair diseases, including alopecia areata, androgenetic alopecia/female pattern hair loss, telogen effluvium, trichotillomania, lichen planopilaris, frontal fibrosing alopecia, central centrifugal cicatricial alopecia, discoid lupus erythematosus, folliculitis decalvans, tinea capitis, and dissecting cellulitis, to confirm the diagnostically meaningful findings for representative diseases. This attempt redefined, for instance, yellow dots, short vellus hairs, exclamation mark hairs, black dots, and broken hairs as the findings of diagnostic significance for alopecia areata and hair diameter diversity, peripilar sign, and focal atrichia for androgenetic alopecia/female pattern hair loss. An updated diagnostic flowchart is proposed with the instructions to maximize its usefulness. Current limitations and future perspectives of trichoscopy as well as other emerging non-invasive diagnostic modalities for hair diseases are also discussed.

Assessment, reliability, and validity of trichoscopy in the evaluation of alopecia in women

Background

Alopecia in women is generally difficult to diagnose clinically. Trichoscopy may help make the correct diagnosis in doubtful cases.

Objective

The aims of the study were to assess the trichoscopic features of different types of alopecia in women, the reliability of trichoscopy vis-à-vis clinical findings, and the validity of trichoscopy in cases with a doubtful clinical diagnosis.

Methods

A hospital-based observational, cross-sectional study was carried out on female patients with alopecia. A trichoscopic diagnosis was made and correlated with a clinical diagnosis. The validity of trichoscopy in doubtful cases was evaluated by reporting the sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic value.

Results

On trichoscopy, increased hair diameter diversity > 20%, single-hair follicular unit, vellus hair, peripilar sign, and focal atrichia were commonly seen in female pattern hair loss. In telogen effluvium, there was a scarceness of specific findings. In cicatricial alopecias, loss of follicular ostia, erythema, white macules, blue-gray dots, white dots, tufted hair, and keratotic follicular plugging were observed. A good agreement between trichoscopy and clinical diagnosis was found (Cohen’s Kappa = 0.824; 95% confidence interval, 0.756–0.892). The validity of trichoscopy in doubtful cases was evaluated using the validity parameters, which were high in all alopecias.

Limitations

Histopathology testing was not done in all patients.

Conclusion

Trichoscopy helped reach a definitive diagnosis in patients in whom the clinical diagnosis was doubtful. Thus, trichoscopy is a sensitive and specific investigation that can be valuable in women with alopecia.

Trichoscopy for the Hair Transplant Surgeon-Assessing for Mimickers of Androgenetic Alopecia and Preoperative Evaluation of Donor Site Area

Preoperative diagnostic confidence and donor site assessment are important for all hair transplant surgery patients. While the majority of patients seek hair transplantation for male or female pattern hair loss (androgenetic alopecia [AGA]), there are mimickers that must be differentiated from patterned hair loss, as they alter the candidacy of the patient for transplantation. They are termed mimickers as they also can present with patterned hair loss. The use of trichoscopy has become increasingly popular for such use. Patterned hair loss mimickers, which include the underappreciated alopecia areata incognita (AAI) and fibrosing alopecia in patterned distribution (FAPD), can be identified clinically with key trichoscopic findings such as yellow dots and peripilar casts, respectively, that correlate with their histologic diagnosis. Donor hair density and putative hair pathology of the safe donor area can also by assessed via trichoscopy. This article discusses the use of trichoscopy, particularly for diagnosing mimickers of patterned hair loss as well as preoperative donor site assessment.

Increased Association between Previous Pregnancies and Use of Chemical Relaxers in 74 Women with Central Centrifugal Cicatricial Alopecia

Background:

Central centrifugal cicatricial alopecia (CCCA) is a type of scarring alopecia exclusively seen in women of African descent. The etiology is unknown and epidemiologic studies including data on comorbidities in patients with CCCA are limited. Our primary objective was to identify possible etiologic and lifestyle associations in patients with CCCA.

Materials and Methods:

A retrospective chart review was conducted for patients diagnosed with CCCA between January 1, 2013, and January 1, 2018, at a university dermatology outpatient clinic. Controls consisted of age-, sex-, and race-matched African–American women diagnosed with other hair loss conditions. Data from 74 cases and 96 controls were collected and analyzed via logistic regression. In addition, a phone survey was conducted in the CCCA cohort asking specific questions related to their condition and quality of life.

Results:

A significant relationship was found between CCCA and previous pregnancies as well as the use of chemical relaxers: patients with CCCA were 11.71 times more likely to have had a previous pregnancy (P < 0.001) and 12.37 times more likely to have used chemical relaxers in the past (P < 0.001). Association with uterine fibroids was found not statistically significant (P > 0.05).

Conclusion:

We identified an association between previous pregnancies and use of chemical relaxers in patients diagnosed with CCCA when compared to controls. These findings may help to plan prospective studies aiming at establishing a more concrete link between hormones and CCCA.

The what, why and how of curly hair: a review

An attempt to understand and explain a peculiarity that was observed for curly fibres during experimentation revealed disparate literature reporting on several key issues. The phenotypical nature of curly fibres is only accurately understood within the larger scope of hair fibres, which are highly complex biological structures. A brief literature search produced thousands of research items. Besides the large amount of information on the topic, there was also great variability in research focus. From our review, it appeared that the complexity of hair biology, combined with the variety of research subtopics, often results in uncertainty when relating different aspects of investigation. During the literature investigation, we systematically categorized elements of curly hair research into three basic topics: essentially asking why fibres curl, what the curly fibre looks like and how the curly fibre behaves. These categories were subsequently formalized into a curvature fibre model that is composed of successive but distinctive tiers comprising the elements in curly hair research. The purpose of this paper is twofold: namely to present (i) a literature review that explores the different aspects of curly human scalp hair and (ii) the curvature fibre model as a systemized approach to investigating curly hair.

Trichoscopy of primary cicatricial alopecias: an updated review

Trichoscopy is an emerging technique for the evaluation of various hair and scalp disorders including primary cicatricial alopecias (PCAs). Early diagnosis of PCAs can lead to effective management and trichoscopy could be a useful aid during this process. Multiple studies have reported the trichoscopic features of PCAs, however, a focused review evaluating these disorders with their trichoscopic features is lacking. With the objective of evaluating the trichoscopic findings reported in the literature for various PCAs, we conducted a systematic literature search in PubMed and Embase. The search yielded 310 studies in a total of which 54 studies were included in our review. Majority of these studies originated from the Caucasian or Asian population. Through this review, we provide an overview of the frequent and specific trichoscopic findings in different PCAs with their clinical significance where applicable based on the current knowledge and identify the areas for future research.