Onychoscopy

Dermoscopic Nail Changes in Psoriasis, Lichen Planus, and Lichen Striatus

Background

Onychoscopy is a noninvasive method helpful in diagnosing nail disorders. The aim of the study was to review literature on the usability of onychoscopy in nail psoriasis, nail lichen planus, and nail lichen striatus.

Summary

Onychoscopic features of nail psoriasis are pitting, onycholysis with erythematous border, salmon patches, splinter hemorrhages, dotted vessels in lateral and proximal folds, and hyponychium. Onychoscopic features of nail lichen planus are onychorrhexis, onycholysis, longitudinal melanonychia, and red lunula. The literature on the usability of onychoscopy in nail lichen striatus is scarce.

Keynotes

Onychoscopy facilitates evaluation of nail abnormalities compared to the clinical examination. Lunular alterations, salmon patches, erythematous border of onycholysis as well as splinter hemorrhages in nail psoriasis are better visualized with onychoscopy compared to the naked eye. Onychoscopy enhances detection of melanonychia, dyschromia, and lunular changes in nail lichen planus. Onychoscopic features are different in fingernails and toenails.

Dermoscopic features of nail psoriasis: a systematic review

INTRODUCTION

Nail psoriasis is common in psoriasis vulgaris and even more prevalent in psoriatic arthritis. Dermatoscopy of the nail proves helpful in enhancing the visualization of psoriatic nail lesions.

OBJECTIVE

This systematic review aimed to summarize the existing studies published in the literature that reported the various dermoscopic features of nail psoriasis.

MATERIALS AND METHODS

A systematic search of two medical databases, PubMed and Scopus, was conducted in April 2023. In total, 11 records were included. The number of reported cases in the included studies was 723.

RESULTS

The average age was 42.39 years. Sixty percent of patients were males, and 40% were females. Pitting constituted the most common onychoscopic feature indicating nail matrix involvement, followed by various other features such as leukonychia, nail plate thickening, transverse and longitudinal ridges, and different lunula abnormalities. The predominant onychoscopic feature indicating nail bed involvement was onycholysis, followed by splinter hemorrhages, oil drop sign, subungual hyperkeratosis, dilated capillaries, agminated capillary dots, erythematous border, and pustules. Vascular abnormalities observed in all locations were present in 52% of patients.

CONCLUSIONS

The clinical signs of nail psoriasis are diverse, and for the majority, they are nonspecific. Nail dermoscopy is a noninvasive tool that enhances the visualization of the nail manifestations of psoriasis. It may facilitate the establishment of diagnostic criteria for this pathology without resorting to more invasive procedures, such as nail biopsy.

A case of superficial acral fibromyxoma masquerading as squamous cell carcinoma of the thumb: A case report

A wide spectrum of tumors may affect the periungual spaces of the digits. Superficial acral fibromyxoma (SAF) is a rare, benign soft tissue tumor with diverse clinical presentations. We present a case of a 55-year-old woman with a 2-year history of a solitary periungual tumor on the left thumb, subjected to multiple episodes of trauma. Initially suspected to be a periungual squamous cell carcinoma (SCC) based on clinical and dermoscopic features, the tumor was confirmed to be a CD34- SAF through histopathology and immunohistochemistry. Although CD34 immunoreactivity is common in SAF, one-third of these tumors, including this case, do not stain for this marker. Periungual SCC considered a "great mimicker of nail tumors," may resemble other benign nail tumors such as SAF. The patient underwent complete surgical excision with primary closure, resulting in no recurrence after 1 year. This case highlights SAF as an underrecognized benign entity that may manifest with features suspicious of malignancy, potentially leading to unnecessarily aggressive interventions. Recognizing SAF through accurate biopsy techniques and thorough histopathologic evaluation, even in the absence of CD34 reactivity, is crucial for appropriate treatment and preservation of hand function and appearance.

Dermoscopic Features of Nail Psoriasis: Revisited

Introduction

Nail psoriasis poses a diagnostic challenge in a context of clinical findings that are not evident. We aimed at exploring dermoscopic findings of nail psoriasis and assessing the relationship between these features with disease severity and the risk of arthritis.

Methods

We enrolled 35 patients (26 men, 9 women) with severe nail psoriasis (Nail Psoriasis Severity Index [NAPSI] score of more than 50). A complete clinical evaluation, including musculoskeletal assessment and videodermoscopic examination of all nails, was carried out for each patient.

Results

Splinter haemorrhage was the most common finding (94.3%), followed by distal onycholysis (88.6%) and pitting (74.3%). The presence of subungual hyperkeratosis (SUH) and the absence of mottled lunula were associated with disease severity (p < 0.05). Both SUH and nail plate crumbling (NPC) were observed more in patients with arthritis. The presence of a combination of SUH and NPC was associated to a 15-fold increase in the risk of arthritis (%95 confidence intervals: 1.55-145.2, p < 0.05).

Discussion/Conclusion

This study presents preliminary evidence for the use of dermoscopy as a first step in the diagnosis of nail psoriasis. Dermoscopy is an indispensable tool in the primary evaluation of patients with nail psoriasis, which provides predictive information about the course of the disease.

Clinical, dermoscopic, and histopathological evaluations of patients with nail disorders

OBJECTIVE

This study aimed to assess the possible role of dermoscopy in the diagnosis of different nail disorders compared with the clinical and histopathological diagnosis.

METHODS

This study included 104 patients with nail disorders of both sex and any age. All the patients were subjected to a detailed medical history taken, clinical general examination, clinical and dermoscopic examinations of 20 nails. Potassium hydroxide examination was used to examine all patients with suspicious of onychomycosis. Histopathological evaluation was used to examine clinically ambiguous nail disorders.

RESULTS

The most common nail diseases were onychomycosis (54.81%) followed by nail psoriasis (19.2%) and nail lichen planus (3.8%).

CONCLUSION

Clinical evaluation was important in the diagnosis of different nail diseases. Nail dermoscopy could confirm clinical diagnosis and help in getting an accurate diagnosis of nail diseases and guide in the management of nail diseases by permitting better visualization of nail structure and pathology. The histopathological examination provided the most definitive method in reaching an accurate diagnosis due to it could provide etiologic, diagnostic, and prognostic information. There was a good agreement between clinical, dermoscopic, and histopathological examinations for accurate diagnosis of different nail diseases.

Dermoscopic features of nail psoriasis: Positive correlation with the severity of psoriasis

Dermoscopy is an efficient and non-invasive technique which has been widely used in the diagnosis of nail disorders including nail psoriasis (NP). Many nail dermoscopic features are considered as clues to NP. The aim of this study was to investigate specific dermoscopic features of fingernail psoriasis and the correlation between the severity of nail lesions or systemic inflammation, and psoriasis severity of skin and nail. This observational study recruited 135 patients with fingernail psoriasis (1186 fingernails) and 30 patients with onychomycosis (80 fingernails). All of the involved fingernails were examined with a handheld dermatoscope. The Nail Psoriasis Severity Index score (NAPSI) score, Psoriasis Area and Severity Index (PASI) score, body surface area (BSA), and detailed history of patients with psoriasis were recorded. Mann-Whitney U-test, χ² -test, Spearman's correlation, and Kruskal-Wallis H-test were used for statistical analysis, and the significance threshold was p < 0.05. The trial registration number was 2020-SR-045. We identified onycholysis as the most common feature (93.3%) of fingernail psoriasis. Red lunula, longitudinal fissures, transverse grooves, nail plate crumbling, trachyonychia, oil-dropping sign, erythematous border of an onycholytic area, subungual hyperkeratosis, and dilated streaky capillaries were relevant to NP severity (p < 0.05). Red lunula, transverse grooves, nail plate crumbling, trachyonychia, oil-dropping sign, erythematous border of an onycholytic area, splinter hemorrhages, and dilated streaky capillaries were relevant to systemic inflammation severity (p < 0.05). The total NAPSI score was positively associated with the PASI score and BSA (p < 0.0001). The thumb had a higher NAPSI score than the other fingers (p < 0.05). In conclusion, dermoscopic features can improve the accuracy of diagnosis of nail psoriasis, and have correlations with psoriasis severity.

Diagnosis of Melanonychia

Melanonychia has many causes and can involve one or several fingernails or toenails, and may occur at any age. Dermoscopy is used routinely in the evaluation of a pigmented nail. If pigmentation is caused by melanin produced by nail matrix, identify whether the pigmentation is caused by an activation or proliferation of nail melanocytes. When melanocytic proliferation is suspected, biopsy with histopathologic examination is the gold standard for diagnosis and is recommended when a longitudinal melanonychia occurs in an adult and is localized in a single digit, in the absence of local or systemic causes that may explain its onset.

Dermoscopy of the Nail Unit

Nail dermoscopy (onychoscopy) is being used for a more accurate diagnosis of all nail disorders and has become a routine diagnostic instrument. In daily practice, nail signs can be magnified, and dermoscopy may confirm the clinical diagnosis and guides in management of nail diseases and treatments, permitting a better visualization of symptoms. Onychoscopy is used by the experts in almost all nail diseases. It can be performed dry or with ultrasound gel in order to make the stratum corneum translucent, depending on which part of the nail unit has to be evaluated.

Dermoscopic characterization of guttate psoriasis, pityriasis rosea, and pityriasis lichenoides chronica in dark skin phototypes: An observational study

Dermoscopy as a diagnostic tool is attaining impetus in inflammatory dermatoses with the cumulative description of characteristic findings in most dermatoses obviating at times the need of biopsy. In this retrospective observational study, 20 histopathology confirmed cases each of pityriasis rosea (PR), guttate psoriasis (GP), and pityriasis lichenoides chronica (PLC) seen over a period of 3 years were included. Dermoscopy images were extracted from photography archives for evaluation and three lesions from each patient (60 lesions each) were analyzed. Comparison of dermoscopy characters was done among PR, GP, and PLC in pairs using chi-square test and a P-value of less than .05 was considered significant. Most common background color in PR (86.7%) and PLC (96.7%) was yellow to yellow-orange and in GP was dull red to pink (70%). Vessels were visualized in all lesions of GP and most characteristic pattern was regular (93.3%), dotted vessels (95%). In PR 63.3% lesions had dotted vessels mostly in a patchy distribution (56.7%). Most prominent scale color in PR was yellow-white (88.3%) and in GP was white-gray (80%). In PLC varying colors were seen, most prominent being brown (53.3%). Characteristic findings seen only in PLC were hypopigmented areas (13.3%), brown dots and globules (53.3%) and orange-yellow structureless areas (61.7%) GP, PR, and PLC reveal specific dermoscopic findings that can help in differentiating them. Further, the known dermoscopic criteria for GP, PR, and PLC also apply for dark skin phototypes.

Melanonychia: Etiology, Diagnosis, and Treatment

Melanonychia is a very worrisome entity for most patients. It is characterized by brownish black discoloration of nail plate and is a common cause of nail plate pigmentation. The aetiology of melanonychia ranges from more common benign causes to less common invasive and in situ melanomas. Melanonychia especially in a longitudinal band form can be due to both local and systemic causes. An understanding of the epidemiology, pathophysiology and clinical details is necessary for adequate patient care and counseling. It not only helps in the early recognition of melanoma but also prevents unnecessary invasive work up in cases with benign etiology. An early diagnosis of malignant lesion is the key to favourable outcome. Though there are no established guidelines or algorithms for evaluating melanonychia, a systematic stepwise approach has been suggested to arrive at a probable etiology. We, hereby, review the aetiology, clinical features, diagnostic modalities and management protocol for melanonychia.

Correlation of Dermoscopic and Histopathologic Patterns in Leprosy - A Pilot Study

Background

Leprosy is a chronic granulomatous disease caused by Mycobacterium leprae. It is diagnosed based on clinical features and confirmed on the histological findings and peripheral slit-skin smear staining. Dermoscopy is a handy, easily accessible tool to diagnose this granulomatous disease and classify patients based on the immunological and clinical response.

Methods

A single spot observational analysis was conducted in a tertiary hospital in North India. Patients attending the leprosy clinic and admitted patients for institutional therapy on the day of the study were enrolled in the cohort. The clinical and histological findings were correlated with the characteristic dermoscopy findings. A total of 50 patients were included in the study. All patents included in the study were on multidrug therapy and anti-lepra reaction drugs for a duration of less than 6 months.

Results

The dermoscopy findings correlated with the clinical and histological findings. Tuberculoid poles of leprosy classically showed loss of hair and skin pigment along with absence of white dots as sweat glands in dermoscopy. Lack of blood vessel changes ruled out any lepra reaction. Lepromatous pole of leprosy on the other hand showed characteristic xerosis and white scaling on dermoscopy in the background of hypotrichosis and hypopigmentation. Leprosy reactions were characterized by blood vessel changes and arborizing blood vessels were characteristic in erythema nodosum leprosum, and a diffuse erythema was a clue toward diagnosing type I lepra reaction. Interestingly, clofazimine-induced pigmentation was picked up characteristically on dermoscopy as a "honey comb pattern".

Conclusion

Dermoscopy is certainly a handy tool in aiding the diagnosis of leprosy, lepra reactions, and course of therapy. Characteristic patterns during the course of leprosy would certainly facilitate a quick and definitive diagnosis of patients suffering from leprosy. Also, patient drug compliance particularly to clofazimine can also be picked up objectively on dermoscopy.

Onychoscopy with red light for vascular pattern identification: a study of 33 patients

BACKGROUND

Nail dermoscopy (onychoscopy) during physical examination assists in correct diagnosis. Often further magnifications are necessary for an effective differential diagnosis. With the addition of a red light to the dermoscope, important vascular features can be visualized.

OBJECTIVE

To describe common features observed at onychoscopy with a new device that combines the regular white light with the red light illumination, demonstrating that it is useful for diagnosis of nail disorders.

METHODS

We enrolled 33 consecutive patients referred to the Nail Diseases Dermatology Unit of the University of Modena and Reggio Emilia and to the Outpatient Consultation for Nail Disease of the Dermatology Unit of the University of Bologna. Patients were assessed with a standard hand-held dermoscope and at the red light dermoscope. Dermoscopic images were collected.

RESULTS

The new prototype was used during daily clinical practice and allowed a more accurate visualization of some details that classic onychoscopy can miss. In particular, with the help of the red light it was possible to better visualize nail lesions that were characterized by some kind of colour change or vascular alterations.

CONCLUSION

The new device of red light for vascular pattern onychoscopy can be a new investigation method to observe nail alterations, especially due to vascular pattern, even with low magnification, without the necessity to use higher resolutions.

Use of Nail Dermoscopy in the Management of Melanonychia: Review

The term melanonychia describes a black-brown-gray pigmentation of the nail plate that, in most cases, appears as a longitudinal band. Melanonychia can be observed at any age, affecting one digit or several digits, in both fingernails and toenails. Its causes can be difficult to differentiate clinically and depend on the number of bands and on their color, edge, and width. For this reason, especially in adults and when the pigmentation is localized in one single digit, biopsy and histopathological examination still represent the gold standard for a definitive diagnosis. Dermoscopy should be used routinely in the evaluation of a pigmented nail, as it provides important information for the management of melanonychia and can help avoid unnecessary nail biopsies. In cases of melanonychia it is important to establish whether the pigment is melanin or not and to determine whether the pigmentation of melanin is due to activation or proliferation and whether it is benign or malignant.

Dermoscopy of Inflammatory Genital Diseases: Practical Insights

Diagnosis of genital inflammatory disorders may be difficult for several reasons, such as their similar appearance, possible misdiagnosis with infectious and malignant conditions, and peculiar anatomic conditions that may lead to modification of clinical features. Dermoscopy could be included as a part of the clinical inspection of genital diseases to support diagnosis, as well as to ideally avoid unnecessary invasive investigation. Practical guidance for the use of dermoscopy in the assessment of the main inflammatory genital diseases is provided, namely for lichen sclerosus, lichen planus, psoriasis, lichen simplex chronicus, and plasma cell mucositis.

Dermoscopy is a new diagnostic tool in diagnosis of common hypopigmented macular disease: A descriptive study

One of the most frequent complaints in dermatology clinics is the eruption of hypopigmented patchy skin lesions. The aim of the study was to investigate the utility of dermoscopy in common hypopigmented macular diseases. Patients with the followings diseases were examined by dermoscopy: vitiligo, pityriasis alba, nevus depigmentosus, achromic pityriasis versicolor, idiopathic guttate hypomelanosis, and extragenital guttate lichen sclerosus.

This study showed that these hypopigmented macular diseases might display specific dermoscopic features. In vitiligo, the mean dermoscopic features were the presence of a diffuse white glow with perifollicular pigment, perilesional hyperpigmentation, leukotrichia and the pigmentary network. In idiopathic guttate hypomelanosis, the characteristic features were the presence of multiple, shiny, scaly macules with welland ill-defined edges borders that coalesced into polycyclic macules. For nevus depigmentosus, the mean features were hypopigmented patches with irregular border with a faint reticular network. For pityriasis alba, the fairly ill-demarcated hypopigmented macules with fine scales were the mean feature. In lichen sclerosus, there were white structureless areas, perilesional erythematous halo, follicular plugging and white chrysalis like structures. Dermoscopy of achromic pityriasis versicolor showed a fairly demarcated white area with fine scales localized in the skin creases.

Onychoscopy of non-infectious nail abnormalities in patients after allogeneic haematopoietic stem cell transplantation

Nail abnormalities after allogeneic haematopoietic stem cell transplantation procedure (alloHSCT) are often reported. Usually, they are related to chronic graft-versus-host disease (cGvHD). So far, only clinical manifestations of selected nail abnormalities have been described, without the presentation of dermoscopic images. In this article, we present morphologic and dermoscopic manifestations of potential non-infectious nail abnormalities in patients after alloHSCT procedure based on reviewed literature and our own experience with dermoscopic iconography. In majority of studies published till now, nail changes are not connected to severity of other cGvHD symptoms; however, e.g. the presence of pterygium inversum unguis may be an indicator of lung dysfunction. As nail changes may be an early sign of cGvHD and always present in association with other manifestations, routine clinical assessment should include nails examination. Knowledge of possible presentation of nail involvement after alloHSCT may be valuable for treating physician.

Alternative uses of dermoscopy in daily clinical practice: An update

Dermoscopy is a noninvasive diagnostic tool that is currently being used for neoplastic skin lesions, several inflammatory and infectious diseases, and skin appendage disorders. As the clinical applications of dermoscopy beyond pigmented lesions are constantly increasing, the aim of this article is to provide an update on this topic. This comprehensive review substantiates how several diseases may show peculiar dermoscopy features so as to enhance the diagnosis and avoid (in selected cases) unnecessary histologic confirmation. In other cases, dermoscopy features may be shared with other conditions, with the advantage of narrowing down the differential diagnosis by ruling out those dermatoses with similar clinical aspect but different dermoscopic presentation.

Onychophagia Induced Melanonychia, Splinter Hemorrhages, Leukonychia, and Pterygium Inversum Unguis Concurrently

Onychophagia, which refers to compulsive nail-biting behavior, is common among children and young adults. Onychophagia can cause destruction to the cuticle and nail plate, leading to shortening of nails, chronic paronychia, and secondary infections. Relatively uncommon effects include pigmentary changes, such as longitudinal melanonychia and splinter hemorrhages. We report a case of a young adult with longitudinal melanonychia, splinter hemorrhages, punctate leukonychia, and pterygium inversum unguis, concurrently induced by onychophagia. Importantly, patients usually do not report this behavior when asked about nail-related changes. Even upon questioning, they may deny nail-biting behavior. As in many other dermatological disorders, dermoscopy can be helpful in the diagnosis of nail disorders.

Improving the diagnosis and treatment of acral melanocytic lesions

Melanocytic lesions of acral sites are common, with an estimated prevalence of 28-36% in the USA. While the majority of these lesions are benign, differentiation from acral melanoma (AM) is often challenging. AM is a unique subtype of melanoma, with distinct molecular characteristics that are thought to contribute to its high rate of locoregional recurrence and worse prognosis. The advent of dermoscopy has since improved the diagnostic accuracy of AM, resulting in earlier detection and arguably improved survival. Additionally, the identification of unique genomic amplifications in AM invites the potential for future AM-specific targeted therapies. Herein, we discuss the importance of dermoscopy in the diagnosis of acral melanocytic lesions and review the treatment strategies for AM.

Dermoscopy in the Evaluation of Nail Disorders

Nail dermoscopy was initially used only in the assessment of nail pigmentation, but now it is widely utilized for the evaluation of many nail disorders. In daily practice, dermoscopy may confirm clinical diagnoses and guides in the management of nail diseases and treatments, permitting a better visualization of symptoms. Dry dermoscopy is required for evaluation of the nail plate surface, while gel as an interface is necessary for assessment of nail pigmentation and onycholysis, as well as for the evaluation of the distal nail margin. In this review, we describe the dermoscopic features of the most important nail disorders, looking at the different areas of the nail. Dermatoscopic changes that usually accompany specific nail diseases are also reviewed.

Dermoscopy in General Dermatology: A Practical Overview

Over the last few years, dermoscopy has been shown to be a useful tool in assisting the noninvasive diagnosis of various general dermatological disorders. In this article, we sought to provide an up-to-date practical overview on the use of dermoscopy in general dermatology by analysing the dermoscopic differential diagnosis of relatively common dermatological disorders grouped according to their clinical presentation, i.e. dermatoses presenting with erythematous-desquamative patches/plaques (plaque psoriasis, eczematous dermatitis, pityriasis rosea, mycosis fungoides and subacute cutaneous lupus erythematosus), papulosquamous/papulokeratotic dermatoses (lichen planus, pityriasis rosea, papulosquamous sarcoidosis, guttate psoriasis, pityriasis lichenoides chronica, classical pityriasis rubra pilaris, porokeratosis, lymphomatoid papulosis, papulosquamous chronic GVHD, parakeratosis variegata, Grover disease, Darier disease and BRAF-inhibitor-induced acantholytic dyskeratosis), facial inflammatory skin diseases (rosacea, seborrheic dermatitis, discoid lupus erythematosus, sarcoidosis, cutaneous leishmaniasis, lupus vulgaris, granuloma faciale and demodicidosis), acquired keratodermas (chronic hand eczema, palmar psoriasis, keratoderma due to mycosis fungoides, keratoderma resulting from pityriasis rubra pilaris, tinea manuum, palmar lichen planus and aquagenic palmar keratoderma), sclero-atrophic dermatoses (necrobiosis lipoidica, morphea and cutaneous lichen sclerosus), hypopigmented macular diseases (extragenital guttate lichen sclerosus, achromic pityriasis versicolor, guttate vitiligo, idiopathic guttate hypomelanosis, progressive macular hypomelanosis and postinflammatory hypopigmentations), hyperpigmented maculopapular diseases (pityriasis versicolor, lichen planus pigmentosus, Gougerot-Carteaud syndrome, Dowling-Degos disease, erythema ab igne, macular amyloidosis, lichen amyloidosus, friction melanosis, terra firma-forme dermatosis, urticaria pigmentosa and telangiectasia macularis eruptiva perstans), itchy papulonodular dermatoses (hypertrophic lichen planus, prurigo nodularis, nodular scabies and acquired perforating dermatosis), erythrodermas (due to psoriasis, atopic dermatitis, mycosis fungoides, pityriasis rubra pilaris and scabies), noninfectious balanitis (Zoon's plasma cell balanitis, psoriatic balanitis, seborrheic dermatitis and non-specific balanitis) and erythroplasia of Queyrat, inflammatory cicatricial alopecias (scalp discoid lupus erythematosus, lichen planopilaris, frontal fibrosing alopecia and folliculitis decalvans), nonscarring alopecias (alopecia areata, trichotillomania, androgenetic alopecia and telogen effluvium) and scaling disorders of the scalp (tinea capitis, scalp psoriasis, seborrheic dermatitis and pityriasis amiantacea).

Clinico-pathologic, dermoscopic and ultrasound examination of a rare acral tumour involving the nail - case report and review of the literature

There is a large spectrum of tumors presenting as nodular lesions that may affect the subungual space. We report the case of a 62-year-old woman presenting with a rapidly growing nodular lesion under the nail of the first left toe. Non-invasive examinations using dermoscopy, ultrasonography and elastography were performed for the preoperative assessment of the lesion. The biopsy of the lesion revealed superficial acral fibromyxoma, a benign tumor with predisposition for acral sites. The patient underwent radical surgery with wide resection margins. This is the first case report of a superficial acral fibromyxoma affecting the subungual region characterized by dermoscopic, ultrasonographic and elastographic features. We also performed a short review of the literature.