Dermoscopic Patterns of Genodermatoses: A Comprehensive Analysis

(1) Background: Genodermatoses are a clinically and genetically heterogenous group of inherited skin disorders. Diagnosing inherited skin diseases is a challenging task due to their rarity and diversity. Dermoscopy is a non-invasive, easily accessible, and rapid tool used in dermatology not only for diagnostic processes but also for monitoring therapeutic responses. Standardized terminologies have been published for its proper use, reproducibility, and comparability of dermoscopic terms. (2) Methods: Here, we aimed to investigate dermoscopic features in various genodermatoses by conducting a systematic review and comparing its results to our own findings, data of patients diagnosed with genodermatoses at the Department of Dermatology, Venereology and Dermatooncology, Semmelweis University. (3) Results: Our systematic search provided a total of 471 articles, of which 83 reported both descriptive and metaphoric dermoscopic terminologies of 14 genodermatoses. The literature data were then compared to the data of 119 patients with 14 genodermatoses diagnosed in our department. (4) Conclusion: Dermoscopy is a valuable tool in the diagnosis of genodermatoses, especially when symptoms are mild. To enable the use of dermoscopy as an auxiliary diagnostic method, existing standardized terminologies should be extended to more genodermatoses.


Introduction
Genodermatoses are a clinically and genetically heterogenous group of inherited skin disorders.These are chronic conditions that present with variable severity of dermatological symptoms and may be associated with extracutaneous manifestations that can have a severe impact on the overall health and quality of life of patients.Diagnosing inherited skin diseases is difficult because these conditions are both rare and diverse.The multistep diagnostic algorithm for inherited skin diseases suggests considering phenotypic features and clinical data, mode of inheritance, target proteins, and genetic variants in the diagnosis of genodermatoses [1].
Dermoscopy is a non-invasive, easily accessible, and rapid tool used in dermatology not only for diagnostic processes but also for monitoring therapeutic responses [2][3][4][5] in the pediatric population [6,7].To ensure correct use, reproducibility, and comparability of dermoscopic terms, in 2015, Kittler et al. published the standardized terminology as a result of the third consensus conference of the International Society of Dermoscopy.To date, both competitive descriptive and metaphorical terminologies have been used in the dermoscopic literature, but the introduction of further metaphorical terms is not recommended [8].Despite this, Errichetti et al. argue that these terms can only be applied to skin neoplasms on which the consensus has focused.Hence, they aimed to define dermoscopic terminology Inherited ichthyoses, also referred to as Mendelian Disorders of Cornification (MeDOC), are a genetically and clinically heterogeneous group characterized by hyperkeratosis, diffuse scaling, xerosis, and a variable degree of erythroderma.The severity of symptoms varies widely due to epidermal barrier defects and various disturbances of the terminal differentiation process of keratinocytes.Non-syndromic types of ichthyoses can be distinguished from syndromic ichthyoses.Ichthyosis vulgaris (IV, ASD, OMIM # 146700) is the most frequent type and is caused by autosomal semi-dominant filaggrin gene (FLG) mutations.The clinical characteristics include fine or prominent scaling over the lower trunk and extremities, palmar hyperlinearity, keratosis pilaris, and frequent association with atopic conditions (Figure 1a,b).X-linked recessive ichthyosis (XLI, XR, OMIM # 308100) occurs almost exclusively in male patients, resulting from steroid sulfatase deficiency, and is caused by deletion of the STS gene locus or gene mutation.XLI is clinically characterized by extensive dark brown polygonal scales, but the flexural areas are not involved (Figure 1c,d).Autosomal recessive congenital ichthyosis (ARCI) is both clinically and genetically very heterogeneous, and 70-90% of the cases present at birth with a collodion membrane.Other cases manifest with signs of abnormal cornification until the fourth week of life [10][11][12][13].On the basis of the inverse relationship between the severity of ichthyosis and erythroderma, the main skin phenotypes are lamellar ichthyosis (LI) and congenital ichthyosiform erythroderma (CIE), although phenotypic overlap can occur.LI (AR, OMIM # 242300) is characterized by generalized large adherent dark scaling with mild erythema (Figure 2c,d); however, CIE (AR, OMIM # 242100) occurs with prominent erythema and fine white scales (Figure 2e,f).Pleomorphic ichthyosis refers to a group of various conditions characterized by a presence of mild congenital ichthyosis with fine scaling that persists after initial skin symptoms during early childhood (Figure 2a,b) [14].Harlequin ichthyosis (HI, AR OMIM # 242500) is a rare severe often fatal form of ARCI, with thick scale plates and deep fissures (Figure 2g,h) [12].
1.1.7.Monilethrix (MNLIX, AD, OMIM # 158000) MNLIX is characterized by hair shaft dysplasia and fragility, resulting in hypotrichosis, especially in the occipital region, or alopecia of variable severity (Figure 9a).Microscopic examination of the hair shaft reveals periodic elliptical nodes and intermittent internodal constrictions leading to characteristic "beaded ribbon" appearance of the hair (Figure 9b).AD forms are associated with mutations in hair keratin genes (KRT81, KRT83, and KRT86) [25].MNLIX is characterized by hair shaft dysplasia and fragility, resulting in hypotrichosis, especially in the occipital region, or alopecia of variable severity (Figure 9a).Microscopic examination of the hair shaft reveals periodic elliptical nodes and intermittent internodal constrictions leading to characteristic "beaded ribbon" appearance of the hair (Figure 9b).AD forms are associated with mutations in hair keratin genes (KRT81, KRT83, and KRT86) [25].Mutations of the ATP-binding cassette subfamily C gene, ABCC6, cause calcification and fragmentation of elastic fibers in the skin, blood vessels, and the retina.It results in increased laxity and loss of elasticity of the skin, arterial insufficiency, and retinal hemorrhages.Dermatological examination reveals multiple coalescing soft yellowish papules with a cobblestone appearance that are symmetrically distributed on the neck, nape, and other flexural areas of the body (Figure 10) [26,27].MNLIX is characterized by hair shaft dysplasia and fragility, resulting in hypotrichosis, especially in the occipital region, or alopecia of variable severity (Figure 9a).Microscopic examination of the hair shaft reveals periodic elliptical nodes and intermittent internodal constrictions leading to characteristic "beaded ribbon" appearance of the hair (Figure 9b).AD forms are associated with mutations in hair keratin genes (KRT81, KRT83, and KRT86) [25].

Pseudoxanthoma Elasticum (PXE, AR, OMIM # 264800)
Mutations of the ATP-binding cassette subfamily C gene, ABCC6, cause calcification and fragmentation of elastic fibers in the skin, blood vessels, and the retina.It results in increased laxity and loss of elasticity of the skin, arterial insufficiency, and retinal hemorrhages.Dermatological examination reveals multiple coalescing soft yellowish papules with a cobblestone appearance that are symmetrically distributed on the neck, nape, and other flexural areas of the body (Figure 10) [26,27].

Connective Tissue Disorder
Pseudoxanthoma Elasticum (PXE, AR, OMIM # 264800) Mutations of the ATP-binding cassette subfamily C gene, ABCC6, cause calcification and fragmentation of elastic fibers in the skin, blood vessels, and the retina.It results in increased laxity and loss of elasticity of the skin, arterial insufficiency, and retinal hemorrhages.Dermatological examination reveals multiple coalescing soft yellowish papules with a cobblestone appearance that are symmetrically distributed on the neck, nape, and other flexural areas of the body (Figure 10) [26,27].FD is an X-linked inherited disorder of the glycosphingolipid metabolism, caused by

Lysosomal Storage Disorder
Fabry Disease (FD, XL, OMIM # 301500) FD is an X-linked inherited disorder of the glycosphingolipid metabolism, caused by a variety of mutations in the alpha-galactosidase A gene (GLA), resulting in progressive accumulation of globotriaosylceramide, especially in endothelial cells, causing multi-organ damage.Angiokeratoma corporis diffusum universale is a distinctive cutaneous manifestation of FD.It is characterized by the presence of widespread angiokeratomas typically located in the bathing suit distribution between the navel and the knees (Figure 11) [28][29][30].

Fabry Disease (FD, XL, OMIM # 301500)
FD is an X-linked inherited disorder of the glycosphingolipid metabolism, cause a variety of mutations in the alpha-galactosidase A gene (GLA), resulting in progressiv cumulation of globotriaosylceramide, especially in endothelial cells, causing multi-o damage.Angiokeratoma corporis diffusum universale is a distinctive cutaneous man tation of FD.It is characterized by the presence of widespread angiokeratomas typi located in the bathing suit distribution between the navel and the knees (Figure 11) 30].TSC is caused by mutations of tumor suppressor genes TSC1 and TSC2, resulting in hyperactivation of the mTOR signaling pathway.It manifests in hamartomas that may affect multiple organs such as skin, heart, lungs, central nervous system, and kidneys.Cutaneous manifestations are hypopigmented "ash-leaf" (Figure 13c,d) and smaller roundish "confetti" macules, facial angiofibromas (Figure 14a,b), shagreen patches (connective tissue nevus, Figure 14c,d), and ungual or periungual Koenen fibromas [32].NF1 is characterized by multiple cutaneous neurofibromas (Figure 12) and café-aulait macules (CALMs, Figure 13a,b), axillar, inguinal or diffuse freckling, and less often juvenile xanthogranuloma or nevus anemicus.It is caused by mutations of the NF1 gene leading to dysfunction of the tumor suppressor NF1 protein (neurofibromin) [31].TSC is caused by mutations of tumor suppressor genes TSC1 and TSC2, resulting hyperactivation of the mTOR signaling pathway.It manifests in hamartomas that m affect multiple organs such as skin, heart, lungs, central nervous system, and kidne Cutaneous manifestations are hypopigmented "ash-leaf" (Figure 13c,d) and smaller rou dish "confetti" macules, facial angiofibromas (Figure 14a,b), shagreen patches (connect tissue nevus, Figure 14c,d), and ungual or periungual Koenen fibromas [32].Mutations in the tumor suppressor gene PTCH1, and in other modifier PTCH2 a SUFU genes, present with multiple early-onset basal cell carcinoma (BCC, Figure 15a palmar and plantar pits (Figure 15c,d), multiple odontogenic keratocysts, and skeletal normalities, and are also alternately associated with a broad spectrum of developmen anomalies and neoplasms [33].CCS is an inherited skin adnexal tumor syndrome caused by mutations in the CLYD gene.It usually manifests in multiple cylindromas, trichoepitheliomas, and spiradenomas located on the head and neck (Figure 16).The size and the number of these appendage tumors typically increase throughout life [34].NSML is mainly caused by defined mutations in the PTPN11 gene.It is characterized by multiple cutaneous lentigines, CALMs, hypertrophic cardiomyopathy and ECG abnormalities, short stature, pectus deformity, dysmorphic facial features, and sensorineural hearing loss [35].Skin lesions include two types of spots.Lentigines are 1-2 mm sized, brown to black colored macules, and increase in number until puberty.Café noir spots are darker and larger than lentigines, up to 5 cm in diameter (Figure 17) [36].CCS is an inherited skin adnexal tumor syndrome caused by mutations in the CLYD gene.It usually manifests in multiple cylindromas, trichoepitheliomas, and spiradenomas located on the head and neck (Figure 16).The size and the number of these appendage tumors typically increase throughout life [34].CCS is an inherited skin adnexal tumor syndrome caused by mutations in the CLYD gene.It usually manifests in multiple cylindromas, trichoepitheliomas, and spiradenomas located on the head and neck (Figure 16).The size and the number of these appendage tumors typically increase throughout life [34].drome, AD, OMIM # 151100) NSML is mainly caused by defined mutations in the PTPN11 gene.It is characterized by multiple cutaneous lentigines, CALMs, hypertrophic cardiomyopathy and ECG abnormalities, short stature, pectus deformity, dysmorphic facial features, and sensorineural hearing loss.[35].Skin lesions include two types of spots.Lentigines are 1-2 mm sized, brown to black colored macules, and increase in number until puberty.Café noir spots are darker and larger than lentigines, up to 5 cm in diameter (Figure 17) [36].

Systematic Review
Our results are reported according to the guidelines of the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) 2020 Statement [37].We registered the review protocol on PROSPERO under registration number CRD42023452448.
Selection and data extraction were conducted by two independent authors using EndNote X9 (Clarivate Analytics, Philadelphia, PA, USA) and Excel spreadsheet (Office 365, Microsoft, Redmond, WA, USA).
The quality assessment was performed using the JBI Critical Appraisal tool for case reports and case series [38,39].

Systematic Review
Our results are reported according to the guidelines of the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) 2020 Statement [37].We registered the review protocol on PROSPERO under registration number CRD42023452448.
Selection and data extraction were conducted by two independent authors using EndNote X9 (Clarivate Analytics, Philadelphia, PA, USA) and Excel spreadsheet (Office 365, Microsoft, Redmond, WA, USA).
The quality assessment was performed using the JBI Critical Appraisal tool for case reports and case series [38,39].

Descriptive Study
The prospective dermoscopic imaging study was carried out in the Department of Dermatology, Venereology and Dermatooncology, Semmelweis University between September 2020 and January 2023.The study was conducted according to the declaration of Helsinki.A total of 119 patients with 14 different inherited disorders were evaluated.Patients with the previously established diagnosis of genodermatosis were included.Exclusion criteria were diagnoses of other skin diseases (e.g., skin infections) that may interfere with dermoscopic features.Diagnosis was confirmed based on the current diagnostic guideline for each disease.Patients gave written informed consent to this study.Demographic data, such as age, gender, and the type of genodermatosis, were documented.All patients underwent detailed clinical examinations.Clinically relevant skin lesions were selected for dermoscopic analysis.Clinical and dermoscopic images were captured.Dermoscopy
tients with the previously established diagnosis of genodermatosis were included.Exclusion criteria were diagnoses of other skin diseases (e.g., skin infections) that may interfere with dermoscopic features.Diagnosis was confirmed based on the current diagnostic guideline for each disease.Patients gave written informed consent to this study.Demographic data, such as age, gender, and the type of genodermatosis, were documented.All patients underwent detailed clinical examinations.Clinically relevant skin lesions were selected for dermoscopic analysis.Clinical and dermoscopic images were captured.Dermoscopy was performed using Illuco IDS-1100C (Illuco Corporation Ltd., Gunpo, South-Korea) and Heine dermatophot (10-fold magnification, Heine Optotechnik GMBH & CO.KG., Gilching, Germany) with an optional polarized light source.All authors evaluated the dermoscopic images.Standardized terminologies and processes suggested by Kittler et al. and Errichetti et al. were applied, with the exception of neurofibromas, where the terms used by Duman et al. were used.Onychoscopic and trichoscopic findings were based on case reports and reviews.Comparison of our own findings to those reported in the literature was carried out.

Systematic Review
Characteristics of studies included for the systematic review are detailed in Table 1.We summarized the findings of the studies included in the systematic review in Table 2.
Table 2. Dermoscopic findings of genodermatoses of the studies included in the systematic review.

Genodermatosis Dermoscopic Findings Described in the Literature
Ichthyosis vulgaris -prominence of linear dermatoglyphic patterning, raised or ragged keratinocyte borders, background erythema, and presence of dull sheen [95] -criss-cross pattern of fine white scale [7,113] X-linked recessive ichthyosis rhomboid/mosaic pattern of brown structures with space in between [7] ARCI-lamellar ichthyosis -multiple large keratotic plugs in the cristae cutis, highly accentuated sulci cutis [97] -quadrilateral brownish structures with fine white scale arranged in lamellar pattern [7] Table 2. Cont.

Descriptive Study
The number of patients, analyzed areas or lesions, and the affected areas for each disease are summarized in Table 3.  4 and 5.Both descriptive and metaphoric terminologies are applied.Metaphoric terms are printed in bold and italics.The trichoscopic and onychoscopic findings are summarized in Table 6.

Discussion
Genodermatoses are a large group of inherited skin diseases whose diagnosis is challenging due to their rarity and clinical and genetic diversity [117].
Given the dynamical development of preclinical and clinical studies in various genodermatoses in recent years to assess the applicability of different targeted therapies (gene, cell-based, protein therapy) and symptom-relief therapies (repurposed and new orphan drugs), it would be important to have non-invasive diagnostic tools for objective assessments of skin conditions.
Dermoscopy is one the useful non-invasive tools in the diagnosis and follow-up of many dermatoses such as inherited rare skin diseases.There are competing descriptive and metaphoric terminologies in the literature.Metaphoric terms may be illustrative and memorable; however, sometimes they may also present a level of ambiguity and lack of clarity, potentially leading to difficulties in everyday clinical practice.Descriptive terminology is clear and logical but may have limitations when describing complex dermoscopic structures.
Standardized dermoscopic terminology by Kittler et al. can be used properly to analyze lesions in FD, NF1, BCNS, NSML, and CCS.Expanded terminology on general dermatology by Errichetti et al. may include parameters describing ichthyoses, PPKs, EKVP, DD, HHD, DDD, PXE, and TSC.For the trichoscopy of MNLIX and onychoscopic analysis, we applied the terms introduced in case reports and review articles.
Dermoscopy is useful for making a diagnosis, especially when skin manifestations are less pronounced.In our results, it was applicable for detecting characteristic papules in one mild case of DD, visualizing an erythematous edge in a newborn with EPPK and trichoepitheliomas in CCS, differentiating angiokeratomas from hemangiomas in FD, and choosing the proper area for biopsy in a mild case of PXE.Dermoscopy may also enhance monitoring of disease activity and accurate follow-up of treatment response.Errichetti et al. successfully used dermoscopy in psoriasis.According to their results, it was useful for following therapy response, detecting steroid-induced skin atrophy by visualizing characteristic linear vessels, and disease recurrence [118].In our cases, steroid-induced skin atrophy could be seen in patients with HHD and DD.In addition, with the use of dermoscopy, we monitored the efficiency of topical therapy for adenoma sebaceum (angiofibroma) in TSC.In our clinical practice, we used dermoscopy for the follow-up of patients with BCNS or NSML to detect potential skin tumors.
Here, we expanded the literature on dermoscopic analysis of many genodermatoses, including nail findings as well.According to recommendations, no new metaphoric terms were added to the literature.To our knowledge, this is the first report on the use of dermoscopy in EPPK, EKVP, and some ARCI such as LI, pleomorphic, and Harlequin ichthyosis.Dermoscopy of PPK and shagreen patch in TSC were described in only one case report of both diseases, including dermoscopic images as well.Our results were similar in dermoscopic features of PPKs; however, in shagreen patch, we described white/light yellow structureless areas with vessels that differed from the findings reported in the literature (reddish brown strands with white lines with a cobblestone appearance) [119].This may be because of the different ethnicities of the two patients.
To use dermoscopy as an auxiliary diagnostic tool in the diagnosis of genodermatoses, existing standardized terminologies (both descriptive and metaphoric) should be expanded to more phenotypes of genodermatoses.

Figure 1 .
Figure 1.Common forms of inherited ichthyoses.Ichthyosis vulgaris is characterized by fine white or light gray scales (a).Dermoscopy shows a criss-cross pattern of fine white scales ((b), arrows).Xlinked recessive ichthyosis manifests in large firmly attached brown rhomboid scales (c).Dermoscopy reveals a mosaic pattern of brown structures with space in between ((d), arrows).

Figure 1 . 36 Figure 2 .
Figure 1.Common forms of inherited ichthyoses.Ichthyosis vulgaris is characterized by fine white or light gray scales (a).Dermoscopy shows a criss-cross pattern of fine white scales ((b), arrows).Xlinked recessive ichthyosis manifests in large firmly attached brown rhomboid scales (c).Dermoscopy reveals a mosaic pattern of brown structures with space in between ((d), arrows).Biomedicines 2023, 11, x FOR PEER REVIEW 4 of 36

Figure 2 .
Figure 2. Autosomal recessive congenital ichthyoses.Pleomorphic ichthyosis (a) manifests in fine white scales (b).Generalized large brown lamellar scaling with mild erythema in lamellar ichthyosis (c).Dermoscopy shows quadrilateral yellow/brown scales (d), arrows arranged in rhomboid pattern (d).Diffuse variable size of polygonal white or light gray scales and background erythema in congenital ichthyosiform erythroderma (e,f).Clinical and dermoscopic images of Harlequin ichthyosis reveal extensive background erythema, dotted vessels, and white scales in variable size and form (g,h).

Figure 2 .
Figure 2. Autosomal recessive congenital ichthyoses.Pleomorphic ichthyosis (a) manifests in fine white scales (b).Generalized large brown lamellar scaling with mild erythema in lamellar ichthyosis (c).Dermoscopy shows quadrilateral yellow/brown scales (d), arrows arranged in rhomboid pattern (d).Diffuse variable size of polygonal white or light gray scales and background erythema in congenital ichthyosiform erythroderma (e,f).Clinical and dermoscopic images of Harlequin ichthyosis reveal extensive background erythema, dotted vessels, and white scales in variable size and form (g,h). Biomedicines 2023, 11, x FOR PEER REVIEW 5 of 36

Figure 3 .
Figure 3. Dowling-Degos disease (a).Dermoscopy shows yellow/brown structureless areas, white globules coalescing into lines ((b), star), and linear vessels ((b), arrows).1.1.3.Palmoplantar Keratodermas Hereditary palmoplantar keratodermas are a heterogeneous group of keratinization disorders marked by excessive thickening of the epidermis of palms and soles.The clinical morphology of hyperkeratosis may be diffuse, focal/striate, or papular/punctate (Figure 4c,d).Mutation analysis is necessary to define the exact type of PPK.Diffuse epidermolytic PPK (EPPK, AD, OMIM # 144200) is the most common diffuse PPK with epidermolytic changes in suprabasal keratinocytes due to mutations in KRT9 and rarely in KRT1 genes.EPPK patients develop confluent fissured brown/yellow hyperkeratosis affecting only palmoplantar surfaces with an erythematous edge (Figure 4a,b).Mutations in the AAGAB gene result in punctate PPK (PPPK, AD, OMIM # 148600) [16].

Figure 6 .
Figure 6.Darier disease.Discrete brownish erythematous hyperkeratotic papules and plaques on the neck (a) and on the back (c) and severe symptoms affecting the lumbosacral region (e).Dermoscopic image of yellow/brown areas ((b,d), arrows) has a polygonal shape, surrounded by white halo representing the acantholytic epidermis.Under dermoscopy, plaque-type lesions appear as erosions, erythematous structureless areas, and yellow/white scales (f).

Figure 6 .
Figure 6.Darier disease.Discrete brownish erythematous hyperkeratotic papules and plaques on the neck (a) and on the back (c) and severe symptoms affecting the lumbosacral region (e).Dermoscopic image of yellow/brown areas ((b,d), arrows) has a polygonal shape, surrounded by white halo representing the acantholytic epidermis.Under dermoscopy, plaque-type lesions appear as erosions, erythematous structureless areas, and yellow/white scales (f).

Figure 9 .
Figure 9. Diffuse hypotrichosis and coarse hair in a patient with monilethrix (a).Trichoscopy reveals periodic thinning of the hair shaft leading to characteristic beaded appearance ((b), arrows).

Figure 8 .
Figure 8. Hailey-Hailey disease.Erythematous plaques with erosions and fissures in the axilla (a).Dermoscopy shows white structureless areas separated by parallel lines and erosions ((b), arrows).

Figure 9 .
Figure 9. Diffuse hypotrichosis and coarse hair in a patient with monilethrix (a).Trichoscopy reveals periodic thinning of the hair shaft leading to characteristic beaded appearance ((b), arrows).

Figure 9 .
Figure 9. Diffuse hypotrichosis and coarse hair in a patient with monilethrix (a).Trichoscopy reveals periodic thinning of the hair shaft leading to characteristic beaded appearance ((b), arrows).

Figure 10 .
Figure 10.Pseudoxanthoma elasticum.Multiple and coalescing asymptomatic soft yellow papules in the axilla (a).Dermoscopy shows yellow/white globules that coalesce into reticular strands ((b), stars) on a light purple background with superficial linear vessels ((b), arrows).

Figure 10 .
Figure 10.Pseudoxanthoma elasticum.Multiple and coalescing asymptomatic soft yellow pa in the axilla (a).Dermoscopy shows yellow/white globules that coalesce into reticular strands stars) on a light purple background with superficial linear vessels ((b), arrows).

Figure 17 .
Figure 17.Clinical picture of multiple lentigines and cafe noir spots in Noonan syndrome with multiple lentigines (a).Dermoscopy reveals brown pigmentation in a cobblestone pattern (b).

Figure 17 .
Figure 17.Clinical picture of multiple lentigines and cafe noir spots in Noonan syndrome with multiple lentigines (a).Dermoscopy reveals brown pigmentation in a cobblestone pattern (b).
was performed using Illuco IDS-1100C (Illuco Corporation Ltd., Gunpo, Republic of Korea) and Heine dermatophot (10-fold magnification, Heine Optotechnik GMBH & CO.KG., Gilching, Germany) with an optional polarized light source.All authors evaluated the dermoscopic images.Standardized terminologies and processes suggested by Kittler et al. and Errichetti et al. were applied, with the exception of neurofibromas, where the terms used by Duman et al. were used.Onychoscopic and trichoscopic findings were based on case reports and reviews.Comparison of our own findings to those reported in the literature was carried out.

Figure 18 .
Figure 18.PRISMA Flow Diagram of the screening and selection process.

Figure 18 .
Figure 18.PRISMA Flow Diagram of the screening and selection process.

Table 1 .
Characteristics of studies included in the systematic review.

Table 3 .
Number of patients and number and localization of lesions analyzed according to different genodermatoses.

Table 3 .
Cont.The dermoscopic analysis of our results following the terminology of Errichetti et al. and Kittler et al. are summarized in Tables

Table A1 .
Results of the risk of bias assessment using the JBI critical appraisal tool (case reports).

Table A2 .
Results of the risk of bias assessment using the JBI critical appraisal tool (case series).
NA-not applicable.