Lines Of Blaschko Research Articles

A case of familial progressive hyperpigmentation with or without hypopigmentation presenting with hypopigmented striae along the lines of Blaschko.

Familial progressive hyperpigmentation with or without hypopigmentation (FPHH) is an autosomal dominant disorder characterized by widespread skin hyperpigmentation, café-au-lait spots, and hypopigmented circular macules, resulting from KITLG variants. KITLG, expressed by keratinocytes, binds to KIT on melanocytes, stimulating melanogenesis. Disturbances in the KITLG-KIT interaction result in diffuse hyperpigmentation in FPHH. However, the mechanisms behind hypopigmented macule formation remain unclear. This report presents a unique FPHH case in a patient with a novel KITLG mutation (Ser78Leu). Notably, the patient showed multiple hypopigmented macules and striae along the lines of Blaschko. Digital polymerase chain reaction analysis of the DNA from skin and blood tissues indicated a copy-neutral loss of heterozygosity at the KITLG locus, only in the hypopigmented macule. These findings suggest that the hypopigmented macules might result from revertant mosaicism. Conversely, café-au-lait spots do not follow the lines of Blaschko and can superimpose on the hypopigmented striae, indicating a distinct pathogenesis. This case contributes to the understanding of the genetic mechanisms in FPHH.

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 abnormalities 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."

Inflammatory Linear Verrucous Epidermal Nevus – Rare Presentation in a Young Female

Inflammatory linear verrucous epidermal nevus (ILVEN) is a rare variant of epidermal nevus characterized by psoriasiform epidermal hyperplasia, pruritic, warty lesions, in a linear configuration, following the lines of Blaschko. We report a rarer incidence of ILVEN in a young adult female presented with pruritic linear focally warty lesion over dorsum of right foot since birth. Histopathological examination of excision biopsy was suggestive of ILVEN. Although generally considered benign, 15-20% ILVEN cases can show malignant transformation. Despite variable treatment options, treatment is custom-made depending upon the nature and extent of the lesion. Therefore, the correct diagnosis of ILVEN is vital for choosing early and prompt treatment planning. Keywords: Adult, ILVEN, Female, Epidermal, Nevus

Lichen planus in children in Kaduna, North-west Nigeria: A 20-year experience

Background: Lichen planus (LP) is a chronic inflammatory disease which mainly affects the skin but may affect mucous membranes and nails. The disease is rare in children. Methods: Retrospective review of records of patients aged < 18 years diagnosed with LP in two dermatology clinics in Kaduna, northwest Nigeria between September 2001 and November 2021. Results: Children constituted 11.3% (38/335) of patients diagnosed with LP: Mean age 10.3 years (range 5 – 16), 44.7% < 10 years, 63.2% male, median duration at presentation - 8 weeks. The legs (68.4%) and lower arms (50%) were the most frequently affected parts of the body. Others were: upper back (34.2%), abdomen (34.2%), lower back (27.2%), chest (23.7%), upper arms (23.7%), elbows/knees (21.1%) and flexural wrists (18.4%). The oral mucosa and genitalia were affected in one patient each. All patients presented with itching while 31.6% and 28.9% of patients presented with post-inflammatory hyperpigmentation and Koebner’s phenomenon, respectively. Classic LP was diagnosed in 90% of patients. Other variants were: hypertrophic (7.9%), annular (6.3%) and on lines of Blaschko (5.3%). There was no significant gender or agerelated difference in presentation. One patient was positive for hepatic C virus infection. Most patients were treated with topical corticosteroids with complete resolution of lesions in 80.8%. During follow-up, recurrence occurred in 3 patients. Conclusion: Lichen planus is more common in Nigerian children than has been reported from many parts of the world. Its presentation is similar to that of adults, although oral and genital involvement is infrequent.

Coexistence of pigmentary demarcation line type B and congenital vitiligo: A unique case report and exploration of potential association

This case report describes a rare occurrence of coexisting Pigmentary Demarcation Line (PDL) type B and congenital vitiligo in a 4-year-old girl. The patient presented with linear band of hyperpigmentation along the blaschko line on the inner sides of bilateral thighs and lower abdomen, accompanied by depigmented patches on the knees, since birth. The clinical history, examination findings, and histopathological analysis supported the diagnosis. The case sheds light on a potential association between PDL and congenital vitiligo, which is not well-documented in the existing literature. Further research and long-term follow-up are recommended to investigate the underlying mechanisms and potential genetic predisposition, providing a deeper understanding of association between these conditions.

Lichenoid drug eruption following the lines of Blaschko caused by 5-fluorouracil metabolite of the pro-drug S-1.

Lichenoid drug eruption following the lines of Blaschko caused by 5-fluorouracil metabolite of the pro-drug S-1.

Linear atrophoderma of Moulin: case report of a rare disease

Linear atrophoderma of Moulin is a rare, acquired, mostly unilateral entity often presenting with hyperpigmented and atrophic band-like skin lesions that follow the lines of Blaschko. There is a considerable amount of overlap among disorders presenting along the lines of Blaschko. In this report, we discuss one such rare case along with its differential diagnosis.

Tissue specific trisomy 15 mosaicism associated with urogenital malformations

We describe a boy born with hypospadias and later diagnosed with vesicoureteral reflux and mild cognitive disability. Routine diagnostic investigation by karyotyping, chromosomal microarray (CMA) and trio analysis with whole exome sequencing was normal. However, later CMA performed on DNA from genital tissue showed trisomy 15, which prompted further analysis.Fluorescent in situ hybridization was performed to verify the CMA result and delineate the mosaic rate. Methylation specific MLPA was performed to investigate the parent of origin of the extra chromosome 15.Further medical examination of the boy identified fine Blaschko's lines, indicative of mosaicism, but earlier unnoticed. CMA on genital tissue showed 80% mosaicism for trisomy 15. Bladder mucosa and muscle showed a high degree of trisomy 15 (56% and 45% respectively), while buccal mucosa and abdominal skin showed low-grade or no trisomy 15. The extra chromosome 15 was of maternal origin.This case report describes a boy with two different malformations in the same organ region that carries a high degree of trisomy 15 mosaicism. Hence, the clinical implication is that there is no recurrence risk for sibs, but the boy in his turn risks producing gametes with an extra chromosome 15. Tissue restricted mutations are not commonly described but may cause congenital malformations that affects the information to the family.

P16 Linear bullous aplasia cutis congenita of the scalp: an unusual presentation of a rare condition

Abstract Aplasia cutis congenita (ACC) is a heterogenous group of congenital disorders characterized by focal or widespread absence of skin. Bullous ACC is a rare variant that presents with well-circumscribed oval lesions resembling bullae or vesicles covered with a thin membrane. There have been 20 previously reported cases of bullous ACC. We present a female neonate referred to dermatology at day 2 of life following an IVF-assisted pregnancy and delivery by elective caesarean section for breech presentation. There was no antenatal history of infection, trauma or drugs, and no relevant family history. Clinical examination of the parietal scalp revealed five well-demarcated bullae in a linear distribution along Blaschko lines. The hair collar and ‘golf club set’ signs were absent. Skin swabs for microbiology and viral studies were negative. Ultrasonography showed no associated osseous defect. Clinical examination was otherwise normal. A diagnosis of multibullous ACC was made, and a conservative approach adopted. Clinical follow up at 2 years found resorption of one bulla with flattening of the remainder. Neurodevelopment was normal. On review of the literature, 10/20 (50%) cases of bullous ACC presented with multiple bullae. The hair collar sign was positive in 50%, strengthening theories that bullous ACC may represent a ‘forme fruste’ of a neural tube defect. Four other cases reported distribution along Blashko lines, suggesting possible underlying cutaneous mosaicism. The majority (90%) had no associated cutaneous or extracutaneous findings. Clinical outcomes were good with spontaneous resorption of bullae, suggesting conservative management is appropriate in most cases.

Linear Lichen Planus Located on Blaschko Lines: A Case Report

Liken planus (LP) deride kaşıntılı, morumsu papüller karakterize olup saç, tırnak, mukoza tutulumu da yapabilen etiyolojisi tam olarak bilinmeyen kronik, inflamatuvar bir hastalıktır. Lezyonun şekline, morfolojisine ve anatomik lokalizasyonuna göre LP sınıflaması yapılmaktadır. Burada bu sınıflama içinde ender görülen Blaschko çizgilerine yerleşen Lineer LP olgusu sunmaktayız.

Linear Psoriasis: A Rare and Often Underdiagnosed form of Psoriasis in Children

Blaschko-linear psoriasis (PBL) is a rare form of psoriasis that presents as longitudinal lines on the skin, along Blaschko lines. This form of psoriasis is often observed in children and can be difficult to distinguish from other acquired Blaschko linear dermatoses such as inflammatory linear verrucous epidermal nevus (ILVEN) and lichen striatus. The prevalence of PBL is unknown, but it is generally observed in children and is more common in boys than in girls. The clinical and histological similarity of PBL to ILVEN presents a diagnostic challenge. In this case report, we present the case of a 7-year-old child with PBL and discuss the diagnostic and therapeutic aspects of this rare form of psoriasis. We were able to confirm the diagnosis of PBL after treatment with white petroleum jelly and salicylic acid petroleum jelly 5% resulted in a significant improvement of the lesions. Topical treatments, phototherapy, and systemic medications can be used in the case of PBL. It is important to select the most appropriate treatment based on the severity of the lesions, the location, and the patient's tolerance, and to keep in mind that PBL can have long-term effects on the quality of life of patients and their families.