Lines Of Blaschko Research Articles

Mosaic Darier's Disease: A Case of Unilateral Localized Type I Segmental Darier's Disease.

Darier's disease (DD), also known as Darier-White disease, is a rare autosomal dominant genodermatosis resulting from mutations in the ATP2A2 gene. It commonly manifests as keratotic papules or plaques in seborrheic areas and is often triggered by heat, sweating, and trauma. A rare mosaic variant, segmental Darier's disease, occurs due to post-zygotic mutations and presents along Blaschko's lines. We describe a 41-year-old male presenting with pruritic, hyperpigmented, keratotic papules distributed unilaterally on the left trunk and upper thigh. The lesions, following Blaschko's lines, worsened with heat. There was no family history of similar conditions. Histopathology revealed classic features of Darier's disease, including irregular acantholysis, dyskeratosis with corps ronds and grains, and suprabasal acantholysis, confirming the diagnosis of type I segmental Darier's disease. Treatment involved corticosteroids twice daily, salicylic acid 2% gel for hyperkeratosis, and lifestyle modifications. Isotretinoin was avoided due to fertility plans. This case highlights the distinctive presentation of type I segmental Darier's disease and underscores the importance of accurate diagnosis through clinical and histopathological correlation. Increased awareness of this rare condition is crucial for timely diagnosis, effective symptom management, and tailored treatment strategies.

Blaschko-Linear Dermatoses: Lichen Striatus with Blaschkitis

Lichen striatus is a rare dermatological condition predominantly affecting pediatric populations, characterized by an erythematous rash of elevated papules forming linear bands along Blaschko's lines. Its etiology remains unclear, though links to environmental factors and atopy are suggested. Blaschkitis, another uncommon inflammatory condition, presents with pruritic papules and vesicular eruptions along the same lines, thought to result from genetically abnormal keratinocytes triggering a T-cell mediated response. This report details a case of a 13-year-old female presenting with hyperpigmented lesions in the axilla, leading to a differential diagnosis of lichen striatus, blaschkitis, and melanocytic nevi. Histopathological analysis confirmed findings consistent with lichen striatus and features of blaschkitis. While the occurrence of these conditions together is rare, their potential interplay warrants further investigation to enhance understanding of their pathophysiology and inform therapeutic approaches. This case highlights the need for continued research into these enigmatic dermatological disorders, particularly within pediatric populations.

Successful treatment of generalized inflammatory linear verrucous epidermal nevus with a somatic mutation in KRT10 with crisaborole 2% ointment.

Inflammatory linear verrucous epidermal nevus (ILVEN) is a rare skin disorder characterized by pruritic, erythematous, hyperkeratotic papules and plaques following the lines of Blaschko. Pathogenesis of ILVEN is not yet clear and treatment remains challenging. We analyzed the molecular basis of generalized ILVEN in a Chinese girl and evaluated the therapeutic effect of topical crisaborole 2% ointment. The patient was found to carry a somatic heterozygous c.467G > A (p.Arg156His) mutation in the KRT10 gene. Expressions of IFN-γ, IL-12, IL-23 and IL-17A at mRNA level in her lesions were elevated. An excellent response was achieved after application of crisaborole 2% ointment. Our data reveal the crucial role of activation of immune response in the development of ILVEN with somatic KRT10 mutations, and suggest crisaborole 2% ointment should be considered for the treatment of ILVEN.

Genotype-phenotype spectrum and correlations in Chinese patients with keratinocytic epidermal naevus: A retrospective study of 22 cases.

Background Keratinocytic epidermal naevus is characterised by hyperkeratotic lesions arranged along Blaschko's lines. So far, multiple genes have been implicated, but there is no detailed data or genotype-phenotype correlation studies of keratinocytic epidermal naevi in Chinese patients. Objective To evaluate the clinical, histopathological and genetic features, genotype-phenotype correlations of keratinocytic epidermal naevus in the Chinese population. Methods A retrospective study of patients with keratinocytic epidermal naevi referred to the Department of Dermatology, West China Hospital, in the last four years. Medical history, clinical data, histopathological characteristics, and evidence of genetic mutations were collected from 22 unrelated Chinese patients with this problem. Results The distribution of the keratinocytic epidermal naevi exhibited right-side dominance. Non-epidermolytic epidermis naevus was much more common. Eight reported missense mutations were found in this study, which were detected in five genes, including HRAS, KRT10, FGFR3, GJB2, and PIK3CA. HRAS was the most commonly affected gene (9/22, 40.91%) in this study, with the c.37G>C (6/22, 27.27%) substitution representing a possible hotspot mutation. Mutation allele loads were higher in the affected lesions than blood samples. Epidermolytic epidermal naevus was found in three patients exclusively carrying KRT10 mutations. Inflammatory epidermal naevi were caused by mutations of KRT10 and PIK3CA. Most of the mosaic mutations detected in keratinocytic epidermal naevi patients were the same as germline mutations identified in systemic diseases caused by these genes. Limitations The retrospective nature of the study. Conclusion Our findings reveal the genotype-phenotype spectrum and their correlation amongst Chinese patients with keratinocytic epidermal naevi. In addition, our data underscores the importance of genetic testing in lesional skin to help characterise and categorise keratinocytic epidermal naevi, decide on a therapeutic strategy, and offer genetic counselling and prenatal diagnosis.

Segmental acantholytic dermatosis (Grover's disease) along Blaschko lines.

Segmental acantholytic dermatosis (Grover's disease) along Blaschko lines.

Linear Hyperpigmented and Depressed Patches Following Blaschko's Lines: A Quiz.

Linear Hyperpigmented and Depressed Patches Following Blaschko's Lines: A Quiz.

Extensive Nevus Comedonicus Along the Lines of Blaschko – Through the Eyes of Dermoscope and Histopathology

Extensive Nevus Comedonicus Along the Lines of Blaschko – Through the Eyes of Dermoscope and Histopathology

Blaschkitis del adulto como fenómeno paraneoplásico. A propósito de un caso

Blaschkitis is an inflammatory skin eruption that that can manifest following the lines of Blaschko. Clinically, it manifests as a recurrent papulovesicular inflammatory dermatitis with a linear distribution. The lesions may appear as narrow lines, though more frequently as broad bands, affecting the trunk either unilaterally or bilaterally. This condition is typically observed in middle-aged individuals. We present the case of an 81-year-old male with a one-year history of an inflammatory plaque in the abdominal region. Histopathological examination of the lesion revealed features consistent with a paraneoplastic syndrome.

Unilateral Extragenital Lichen Sclerosus Following Blaschko's Lines.

Lichen sclerosus is a chronic, immune-mediated dermatologic disorder primarily affecting the genital skin. Extragenital lichen sclerosus is rare, especially in men. We present a case of ELS in a 23-year-old male with lesions on the left upper extremity that had persisted for seven years. Over time, the lesions gradually spread to the left upper arm and scapular region. These lesions followed a band-like distribution along Blaschko's lines, without associated pruritus or pain. This unusual presentation posed a diagnostic challenge, highlighting the rarity of such manifestations.

Histopathological Perspective of Linear and Whorled Nevoid Hypermelanosis in Adulthood: A Rare Case Report

ABSTRACT A rare pigmentation disorder called linear and whorled nevoid hypermelanosis (LWNH) is characterized by macular hyperpigmentation that follows the Blaschko lines. The cheeks, palms, soles, and mucosae are typically spared from lesions and are typically limited to the trunk, neck, and extremities. Although it is usually benign, there have been reports of associations with many congenital abnormalities. Herein, we present a rare case of LWNH involving the lateral surface of the abdomen in a 22-year-old male patient. A punch biopsy from the skin was received, and based on the histomorphological features, a diagnosis of LWNH was given. Hence, histopathology is the gold standard and confirmatory tool for definite diagnosis, along with other dermatological and genetic investigations in this case.

Linear and whorled nevoid hypermelanosis: A report of two unusual cases of pigmentary mosaicism

Linear and whorled nevoid hypermelanosis (LWNH) is a rare pigmentary disorder presenting with brownish macules in a streaky configuration along the lines of Blaschko. A 5-year-old and a 6-year-old girl presented with multiple linear streaks of hyperpigmentation following the lines of Blaschko over the left half of their bodies for 2 years. The 5-year-old girl child also had several depigmented patches on her right arm and side of her back that were arranged in a segmental pattern. Dermoscopy of the depigmented patches showed a diffuse white color with leukotrichia, whereas hyperpigmented patches showed brownish curved lines, dots, and clods with focally dispersed whitish globules and lines. Here, we report one case of LWNH associated with segmental vitiligo and two girls with late-onset LWNH.

Nevus Unius Lateris (NUL) in a Theree-Year-Old Child Treated by Tretinoin 0.025%, Desoxymethasone 0.25%, and Urea 20% Cream

Background: Linear verrucous epidermal nevus is the most frequent variant of the epidermal nevus classification. Linear verrucous epidermal nevus is characterized by the proliferation of epithelium arranged in a configuration that follows Blaschko's line. Nevus unius lateris (NUL) is a variant of the verrucous epidermal nevus, which has a unilateral distribution of lesions. Lesions are usually found at birth or in the first year of life as brown to grey verrucous papules or papillomatous plaques. The management of NUL is challenging as the results are varied and there is a high risk of recurrence. Purpose: to report a case of NUL and its management, especially in children. Case: A 3-year-old girl presented with brownish spots and multiple small lumps on the left buttock that have extended to the left leg since she was 9-days-old. On dermatologic examination, there were numerous hyperpigmented verrucous papules and plaques along the Blaschko line over the affected area. In this case, the diagnosis of NUL, is based on clinical symptoms and dermoscopy examination showed multiple large brown oval or round structures with hyperpigmented brown border. The patient was treated with combination topical therapy of tretinoin 0.025%, corticosteroid desoxymethasone 0.25%, and urea 20% cream, and the lesion improved within four weeks. Discussion: Epidermal nevus is often cosmetically disturbing. The treatment is still challenging and various, including surgical and non-surgical, but none is ideal and could potentially recur over months or years. dst.

Linear atrophoderma of Moulin: A rare case report and review of the literature.

Linear atrophoderma of Moulin (LAM) is an uncommon dermatological disease characterised by linear, depressed plaques typically following Blaschko's lines. LAM generally occurs in adolescence or early adulthood and is more commonly observed in females. The aetiology of LAM is still unclear. We report a rare case of LAM in an 18-year-old female presenting with an atypical Blaschkoid distribution (multiple band-like pattern) on her right trunk. A clinical examination and histopathological analysis were performed to make the diagnosis. Partial improvement was obtained with calcipotriol and colchicine. LAM is a rare condition; we were only able to identify 23 case reports in the published literature. The findings of this report contribute to the limited literature on LAM, highlighting the clinical variability of LAM and suggesting potential novel variants beyond the classic presentation, emphasising the importance of recognising diverse manifestations for accurate diagnosis and management. Early recognition of LAM is crucial for appropriate treatment and improved patient outcomes. Further research is needed to elucidate LAM's aetiology and underlying mechanisms to facilitate the development of more targeted therapeutic strategies.

Naevoid blaschkoid psoriasis: a curable mosaic abnormality of the skin.

Naevoid Blaschkoid Psoriasis is a rare and underdiagnosed subtype of linear psoriasis. Characteristic aspects of naevoid blaschkoid psoriasis include a late onset of asymptomatic erythematous and scaly plaques along with blaschko line. Here, we report on a patient with a delayed definitive diagnosis of mosaic pattern skin in early infancy, who experienced significant clearing of skin plaques after treatment with an interleukin 17 (IL-17) inhibitor (secukinumab). This case reminds clinicians to take psoriasis into consideration under the differential diagnosis of blaschkoid dermatoses.

Case of Unilateral Linear Lichen Planus with Bilateral Mucosal Involvement

Abstract A form of lichen planus (LP) which follows the Blaschkos line pattern known as linear LP, presents with lichenoid eruptions and violaceous papules in a linear distribution. It is a rare form of LP affecting <0.2% population with LP. We present a case of a 52-year-old female with hyperpigmented patches and plaques distributed linearly along the Blaschkos line in her right leg. From a clinical perspective, the lesions on the patient’s right leg resembled those of lichenoid epidermal naevus, which is a type of linear verrucous epidermal nevus but the dermoscopic findings and the presence of oral mucosa LP indicate that the patient has the uncommon variant of LP which is called linear LP. It is thus critical for clinicians to distinguish linear LP from other acquired dermatoses following the lines of Blaschko both clinically and dermoscopically.

Facial Segmental Infantile Haemangioma: A Cutaneous Mosaicism Quandary.

Mosaicism has long been considered the underlying mechanism of segmental infantile hemangiomas (SIH). This was a prospective pilot case-control study conducted with the objective to quantify the percentage overlap of silhouettes of facial SIH with those of Blaschko lines (the most well studied archetypical pattern of mosaicism on face) as compared to other mosaic disorders on face. Lesional silhouettes of 8 patients with SIH (Group A) and 6 patients with other facial dermatosis known to have blaschkoidal distribution (Group B), were overlapped on a standardized template with Blaschkoidal lines on the frontal view of face. The alignment was done via the auto align tool of Photoshop and the percentage of overlap was calculated with an online image comparison software (IMGonline.com.ua). There was a significant difference in mean overlap in Group A (72.92 ± 15.6 %) as compared to Group B (90.1 ± 4.3%; P=0.018). Hence, we concluded that facial SIH do not follow lines of Blaschko.

Lichen Striatus: An Updated Review.

Lichen striatus is a benign dermatosis that affects mainly children. This condition mimics many other dermatoses. The purpose of this article is to familiarize pediatricians with the clinical manifestations of lichen striatus to avoid misdiagnosis, unnecessary investigations, unnecessary referrals, and mismanagement of lichen striatus. A search was conducted in June 2023 in PubMed Clinical Queries using the key term "Lichen striatus". The search strategy included all observational studies, clinical trials, and reviews published within the past ten years. Only papers published in the English literature were included in this review. The information retrieved from the above search was used in the compilation of this article. Lichen striatus is a benign self-limited T-cell mediated dermatosis characterized by a linear inflammatory papular eruption seen primarily in children. The onset is usually sudden with minimal or absent symptomatology. The eruption in typical lichen striatus consists of discrete, skin- colored, pink, erythematous, or violaceous, flat-topped, slightly elevated, smooth or scaly papules that coalesce to form a dull red, potentially scaly, interrupted or continuous band over days to weeks. Although any part of the body may be involved, the extremities are the sites of predilection. Typically, the rash is solitary, unilateral, and follows Blaschko lines. In dark-skinned individuals, the skin lesions may be hypopigmented at onset. Nails may be affected alone or, more commonly, along with the skin lesions of lichen striatus. The differential diagnoses of lichen striatus are many and the salient features of other conditions are highlighted in the text. Lichen striatus is a self-limited condition that often resolves within one year without residual scarring but may have transient post-inflammatory hypopigmentation or hyperpigmentation. As such, treatment may not be necessary. For patients who desire treatment for cosmesis or for the symptomatic treatment of pruritus, a low- to mid-potency topical corticosteroid or a topical immunomodulator can be used. A fading cream can be used for post-inflammatory hyperpigmentation.

Association between the skin microbiome and lichen striatus hypopigmentation: Cutibacterium acnes as a potential cause.

Lichen striatus (LS) is an acquired skin disorder with a linear pattern along Blaschko's lines. It commonly occurs in childhood, and the lesions spontaneously regress within several months. Although up to 50% of LS cases exhibit hypopigmentation that can persist for several months to years, it is unknown why LS is associated with such a high incidence of hypopigmentation compared to other inflammatory skin diseases. Therefore, this study aimed to analyse the differences in the skin microbiome between LS patients with and without hypopigmentation. Differences in skin microbiome were analysed using whole genome sequencing of skin biopsies and subsequent bioinformatics analyses. Some microbes commonly found in hypopigmented skin disorders, including Cutibacterium acnes, were more abundant in patients with LS showing hypopigmentation than in those not showing hypopigmentation. The skin microbiota may be involved in the development of hypopigmentation in LS and may be considered a treatment target to reduce LS duration and hypopigmentation.

Warts as a common occurrence on nevus sebaceous: A case series depicting locus minoris resistentiae

Locus minoris resistentiae (LMR) is a special site that offers less resistance to the onset of disease than the rest of the body. Areas of cutaneous mosaicism may act as congenital LMR sites. Viral infections such as verruca are a rare occurrence on these sites. Nevus sebaceous is a benign hamartoma with epidermal, follicular, and apocrine mosaicism in the stem cells that expand in the lines of Blaschko, which may act as a site of LMR. Herein, we present a case series of nevus sebaceous to document the occurrence of verrucae and the possibility of LMR at these sites. Key words: Wart, Locus minoris resistentiae, Nevus sebaceous

Incontinentia pigmenti Stage 1 is not simply vesiculo-bullous but vesiculo-pustular.

Incontinentia pigmenti (IP) is a rare X-linked dominant, male-lethal disorder characterized by pathognomic skin lesions. As described in the literature the typical cutaneous changes follow the pattern of Blaschko's lines and develop in four stages that usually start at birth. Stage 1 is called vesicular, bullous or inflammatory. The vesicles are rapidly filled with eosinophils and thus turn into pustules. Thus, the term "pustular" is relevant to the first phase of IP, and the stage can be considered as "vesiculopustular/inflammatory" to be more precise than "vesicular" or "bullous."