Clinical Characteristics and Therapeutic Aspects of Blaschko Linear Psoriasis.

INTRODUCTION: Blaschko linear psoriasis (BLP) is characterized by the linear distribution of psoriatic skin lesions along the Blaschko lines. BLP can be divided into type I and type II, mainly on the basis of clinical manifestations. BLP can easily cause psychological burdens in patients and clinical confusion for physicians. Here, we summarize clinical cases to provide a better understanding of BLP. METHODS: The subjects included patients with BLP who visited our dermatology departments and those reported in the literature obtained from the PubMed and Wanfang databases. Quantitative data were presented as means ± SD (standard deviation), and qualitative data were represented by the frequency. Student's t test was employed to compare means, whereas chi-square tests were used for analyzing qualitative data. RESULTS: A total of 74 patients with BLP (5 our patients, 69 from literature) were included, with 61 type I and 13 type II patients. We summarize BLP's characteristics as follows: (1) More frequent in male individuals, especially in type II; (2) Earlier onset than classical psoriasis; (3) Mainly distributed unilaterally, and no preference for left or right site; (4) Asymptomatic or slight pruritus; (5) Mostly negative family history of psoriasis; (6) Possible involvement of the nails/scalp (mainly for type II); (7) Possible exogenous triggering or aggravation factors; (8) Possible concomitant classical plaque or guttate psoriasis lesions, especially in type II; (9) Conforming to histopathology features of classical psoriasis; (10) Relatively favorable response to antipsoriatic treatment, although poor for superimposed areas in type II. CONCLUSION: This study analyzed the clinical characteristics and therapeutic aspects of BLP. Compared with published studies, we have new findings, such as gender bias. Besides traditional antipsoriatic treatment, a personalized selection of biologics may also be a promising choice. Dermatologists should recognize and understand the significance of this disease, and provide patients with appropriate psychological counseling and clinical treatments.

Linear and Whorled Nevoid Hypermelanosis - A Case of Pigmentary Mosaicism.

Linear and whorled nevoid hypermelanosis is a rare skin pigmentation disorder, characterized by linear streaks and whorls of hyperpigmented macules along Blaschko's lines. Lesions are commonly restricted to the trunk, neck, and extremities, sparing the face, palms, soles, and mucosae. Associated with this, certain cardiovascular, musculoskeletal, neurological, and developmental anomalies have been reported in the literature. Herein, we present a rare case of linear and whorled nevoid hypermelanosis involving the face, with musculoskeletal, genital, aural, and ocular abnormalities.

Lichen Striatus: An Updated Review.

BACKGROUND: Lichen striatus is a benign dermatosis that affects mainly children. This condition mimics many other dermatoses. OBJECTIVE: 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. METHODS: 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. RESULTS: 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. CONCLUSION: 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.

Successful treatment with baricitinib of linear morphea following the lines of Blaschko mimicking lichen striatus.

Linear morphea, also known as linear scleroderma, is a localized form of scleroderma characterized by the presence of lesions that follow a linear distribution pattern. Apart from the typical inflammation and fibrosis of the skin, the linear subtype of morphea often affects underlying structures such as muscles and bones, which can lead to functional limitations. Lichen striatus, a linear inflammatory skin condition, primarily affects children aged 5 to 15 years. Interestingly, both diseases can exhibit lesions that follow the lines of Blaschko. Here we report a case with linear morphea following the lines of Blaschko mimicking lichen striatus in a 4-year-old child. This unique case represents the first documented instance of linear morphea exhibiting a precise Blaschko pattern and being successfully treated with baricitinib. The patient received oral baricitinib at a daily dosage of 2 mg for a duration of 1 year, resulting in remarkable improvement. The majority of the lesions softened, and there was no significant disease progression or occurrence of adverse events throughout the treatment period. Recognizing linear morphea at an early stage is of utmost importance in ensuring effective treatment and preventing disfiguring sequelae. Patients suspected of lichen striatus should also be closely followed and linear morphea should be excluded during the follow-up. The recent breakthrough in the application and the safety of baricitinib in scleroderma is also reviewed.

A Case of Unilateral Blaschko-Linear Lichen Planus Pigmentosus in a Seven-Year-Old Female: A Rare Presentation.

Lichen planus pigmentosus (LPP) is a rare form of lichen planus that typically affects middle-aged people with darker-pigmented skin. LPP is associated with a longer clinical course than classical lichen planus, which distinguishes it clinically. Its occurrence in children is uncommon, with few reported cases in this population in the literature. We report a rare presentation of unilateral blaschkoid LPP in a seven-year-old Saudi Arabian female patient.

Unilateral Lichen Planus Pigmentosus with Blaschko's Line Distribution: A Case Report.

Lichen planus pigmentosus (LPP) is a distinctive variant of lichen planus described for the first time in 1974. A wide range of presentations and distribution patterns have been reported, mainly presenting as dark brown hyperpigmented macules and patches, typically involving sun-exposed areas such as the face, neck, and flexural folds. It is more common in dark-skinned patients with a female predominance. Infrequently, LPP may present as a Blaschkoid distribution, with only a few cases reported in the medical literature. We report an unusual case of LPP that developed with a unilateral Blaschkoid distribution on the left side of the trunk in a 32-year-old female following weight reduction surgery.

Atypical Linear Atrophoderma of Moulin Complicated with Elevated Immunoglobulin M: A Case Report.

Linear atrophoderma of Moulin (LAM) is a rare acquired skin disease. Clinically, LAM is characterized by hyperpigmented and atrophic unilateral band-like or linear dermatoses of variable size following the Blaschko lines. The lesions do not present induration or sclerosis. Its course is asymptomatic without systemic involvement or progression. The etiology of LAM is still unclear. Based on the characteristics of its skin lesions distributed along the Blaschko lines, some scholars speculate that its pathogenesis may be related to chromosome mosaicism. We hereby present a case report of LAM in a 29-year-old Chinese female who had persistent brown patches distributed along the Blaschko lines on the left lower back, buttocks, and lower limbs with positive antinuclear antibody (ANA, 1:320, nucleolar type) and elevated immunoglobulin M (3.47 g/L). Including this case, a total of 6 LAM cases have been reported to have abnormal serum immunological markers.

Reflectance confocal microscopy-assisted diagnosis of lichen planus pigmentosus distributed along multiple unilateral Blaschko's lines in a child: A case report.

A boy with a 2-year history of asymptomatic, linear pigmented macules involving the right side of the trunk and right upper limb. RCM revealed the dermal papillary rings were destroyed, and numerous irregular particulate structures with high refractive values were distributed in the superficial dermis. The RCM features implied the possibility of interface dermatitis. RCM was a complementary diagnostic tool for linear pigmented macules.

Pigmentary mosaicism as a recurrent clinical manifestation in three new patients with mosaic trisomy 12 diagnosed postnatally: cases report and literature review.

BACKGROUND: To date, only twenty-one cases diagnosed postnatally with mosaic trisomy 12 have been reported. The most frequent phenotypic manifestations are developmental delay, dysmorphic facial features, congenital heart defects, digital alterations, and pigmentary disorders. In the present report, detailed clinical and genetic profiles of three unrelated new patients with mosaic trisomy 12 are described and compared with previously reported cases. CASE PRESENTATION: In the present report, we include the clinical, cytogenetic, and molecular description of three Mexican patients diagnosed postnatally with mosaic trisomy 12. At phenotypic level, the three patients present with developmental delay, dysmorphic facial features, congenital heart defects and skin pigmentary anomalies. Particularly, patient 1 showed unique eye alterations as bilateral distichiasis, triple rows of upper lashes, and digital abnormalities. In patient 2 redundant skin, severe hearing loss, and hypotonia were observed, and patient 3 presented with hypertelorism and telecanthus. Hyperpigmentation with disseminated pigmentary anomalies is a common trait in all of them. The cytogenetic study was carried out under the strict criteria of analysis, screening 50-100 metaphases from three different tissues, showing trisomy 12 mosaicism in at least one of the three different tissues analyzed. With SNParray, the presence of low-level mosaic copy number variants not previously detected by cytogenetics, and uniparental disomy of chromosome 12, was excluded. STR markers allowed to confirm the absence of uniparental disomy as well as to know the parental origin of supernumerary chromosome 12. CONCLUSIONS: The detailed clinical, cytogenetic, and molecular description of these three new patients, contributes with relevant information to delineate more accurately a group of patients that show a heterogeneous phenotype, although sharing the same chromosomal alteration. The possibility of detecting mosaic trisomy 12 is directly associated with the sensitivity of the methodology applied to reveal the low-level chromosomal mosaicism, as well as with the possibility to perform the analysis in a suitable tissue.

Unilateral lichen planus with Blaschko line distribution: A case report.

BACKGROUND: Lichen planus (LP) with distribution of lesions along Blaschko's lines is a rare entity, accounting for 0.24%-0.62% of all patients. Unilateral distribution of lesions in arm, leg, trunk, and waist is even less common. Approximately 10% of patients with LP manifest nail lesions. CASE SUMMARY: A 20-year-old woman presented to our department with polygonal, purpuric, flat-topped papules over the right arm, right leg, and right side of trunk and waist for the last 5 mo. The patient initially developed nail deformation in the left middle finger with no obvious cause, followed by development of blue-purple and red maculopapular rash with pruritus. During the disease course, the skin lesions aggravated and spread to several segments due to scratching. The lesions showed unilateral distribution along the Blaschko's lines. The diagnosis of LP along Blaschko's lines was established based on dermoscopy and skin biopsy. Her cutaneous lesions considerably improved after 4-wk treatment with intramuscular glucocorticoid, oral acitretin, topical glucocorticoid, and retinoids. CONCLUSION: Cases of LP involving multiple segments of the body along the Blaschko's lines with nail damage are rare.

Dermoscopy in the Diagnostics of Incontinentia Pigmenti Skin Lesions.

Introduction: Incontinentia pigmenti (IP) is a rare X-linked geno-dermatosis characterized by numerous findings. Skin biopsy and histopathological analysis are considered as minor criteria for the diagnosis of IP. We assume that dermoscopy can assist the earlier diagnosis of IP. Objectives: To gain experience in earlier diagnosis of IP by observing dermoscopic findings of cutaneous changes. Methods: We revised confirmed cases of IP and examined them using dermoscopy, comparing histopathological and dermoscopic results. Results: Stage I presented solitary and grouped vesicles in linear arrangement on erythematous skin. Early stage II presented star-shaped verrucous lesions on erythematous or pigmented skin. In well-developed lesions, dotted vessels surround keratotic part, some with thrombosed capillaries, resembling a viral wart. Stage III presented linear brown dots on the pigmented areas. Dermoscopic image was uniform in all the examined pigmented Blaschko linear changes. Stage IV presented numerous dotted vessels on the hypopigmented skin. Terminal hair was scarce or absent in all four stages. The surrounding normal skin had perifollicular depigmentations in stages III and IV. Conclusions: Dermoscopy of all four stages is very specific compared to the dermoscopy of inflammatory dermatoses and pigmentations. Stage III has very close clinical, histological and dermoscopic mimickers and needs to be carefully examined with obligatory genetic testing. Dermoscopy of the stage IV closely corresponds to histopathological findings and may be crucial as a quick tool in revealing potential IP gene carriers. Dermoscopy should be used in addition to clinical examination since the two methods are complementary.

A Case of Linear Exacerbation of Atopic Dermatitis with Secondary Prurigo Nodularis.

Inflammatory acquired Blaschko-linear dermatoses (IABLD) are a continuous concept involving diseases such as lichen striatus, blaschkitis, and atopic dermatitis. However, atopic dermatitis that showed increase in severity along Blaschko lines is rarely reported on its own. Herein, we report a rare case of atopic dermatitis with secondary prurigo nodularis along Blaschko lines, which may be valuable in broadening the concept of IABLD. A 28-year-old male presented with multiple, pruritic, brownish nodules on the left lower extremity along Blaschko lines for 3 to 4 years. The patient had atopic dermatitis since childhood. Histopathologic findings revealed compact orthohyperkeratosis, hypergranulosis, spongiosis, and irregular acanthosis in the epidermis. Fibrosis with vertically arranged collagen fibers and perivascular lymphohistiocytic infiltration were shown in the upper dermis. We diagnosed the case as secondary prurigo nodularis along Blaschko lines, accompanied by the preceding atopic dermatitis. We hypothesized that the patient's underlying atopic dermatitis increased in severity along Blaschko lines, and prurigo nodularis occurred due to frequent scratching. The lesions improved with topical methylprednisolone cream, oral antihistamines and intralesional triamcinolone injection.

Positive Antinuclear Antibody and Blaschkoid Lichen Planus Pigmentosus.

Lichen planus pigmentosus is a rare variant of lichen planus. It is an acquired pigmentary disorder of unknown etiology. It is characterized by dark brown and slate gray macules and patches. The nails, scalp, and oral mucosa are usually spared, unlike lichen planus. Lichen planus pigmentosus commonly involves the head and neck region as well as intertriginous areas such as the axillae, inframammary and inguinal regions. It can be associated with autoimmune diseases, endocrinopathies, and other variants of lichen planus such as fibrosing alopecia of the scalp. Variable clinical patterns of lichen planus pigmentosus including zosteriform, linear, and segmental had been published. Histopathologically, it is characterized by hyperkeratosis of the epidermis, hypergranulosis, variable degrees of lichenoid infiltration depending on the age of the lesion, and prominent melanin incontinence. Recent updates on erythema dyschromicum perstans that were considered similar to lichen planus pigmentosus, concluded that they could be differentiated on clinical bases as well as histopathology. Epidermal hyperkeratosis, hypergranulosis, apoptotic cells, lichenoid dermatitis, periappendageal infiltrate, and fibrosis with marked superficial dermal melanin incontinence aid to differentiate lichen planus pigmentosus from erythema dyschromicum perstans. During embryogenesis, cells migrate and follow developmental lines named after Blaschko, a German dermatologist, who first noted them. Blaschko's lines (BL), do not follow neural, vascular, or lymphatic pathways. They appear as V-shaped on the back, S-shaped on the abdomen, and linearly on limbs. We report a case of lichen planus pigmentosus over BL that is a rare presentation of the disease and associated positive antinuclear antibody (ANA) without overt manifestations of any connective tissue disease.

Blaschko-linear lichen planus of the face: A retrospective study of 6 cases and a literature review.

INTRODUCTION AND METHODS: Different clinical and histological variants of lichen planus (LP) exist, such as lichen planopilaris, pigmentosus, linear, or atrophic LP. Recently, some cases came to our attention of hyperpigmented and atrophic linear lesions of the face with lichenoid histology, suggesting a combination of these different variants. We carried out a single-center, retrospective descriptive study of 6 similar cases selected from our database and compared them with a literature review. RESULTS: There were 4 males and 2 females of mean age 42 years. Each had linear lesions located on one side of the face. All lesions were initially itchy; they appeared hyperpigmented in all patients and atrophic in 5 cases. Biopsies indicated lichen planopilaris in 5 patients, with deep peri-eccrine involvement in 4 of them. Only 2 of the 6 patients had extra-facial lesions. DISCUSSION AND LITERATURE REVIEW: We found 24 cases in the literature having similar clinical and histological aspects. Men aged around 37 years seemed particularly affected. An atrophic course was noticed in 10 patients. Such a clinicopathological picture may suggest differential diagnoses like lichen striatus, lupus erythematosus, lichen sclerosus atrophicus, or Moulin's linear atrophoderma. Early histopathological examination could be of precious assistance in allowing the initiation of effective treatment immediately as of the initial inflammatory phase, thereby limiting the risk of cosmetic sequelae such as atrophy or residual pigmentation. CONCLUSION: We describe a form of facial lichen planus that is highly particular in terms of its follicular tropism, its blaschkoid distribution, its pigmented character, and its atrophic progression.