A Case of Naevoid Blaschkoid Psoriasis in a Two-Year-Old Child

Psoriasis is a chronic, immune-mediated skin disorder characterised by well-demarcated erythematous plaque with micaceous scale. Naevoid Blaschkoid psoriasis is an unusual subtype that occurs along Blaschko lines. A two-year-old boy presented with erythematous scaly lesions distributed along the lines of Blaschko over the bilateral upper limb, the front of the chest, back, and the right lower limb. The lesions appeared four months ago and slowly progressed. There was no history of trauma, no skin lesions in other parts of the body, and no significant family history. Nail and mucosa were normal. Histopathology showed psoriasiform dermatitis with characteristics of psoriasis. The child was treated with topical clobetasol propionate 0.05% cream. Naevoid Blaschkoid psoriasis, in the absence of psoriatic lesion elsewhere on the body, is a rare manifestation. It has striking similarity with inflammatory linear verrucous epidermal nevus (ILVEN), both clinically and histologically. Naevoid psoriasis usually presents late, is asymptomatic or mildly pruritic, progresses rapidly, and responds favourably to antipsoriatic treatment. In contrast, ILVEN presents early, is intensely pruritic, slowly progressive, and is usually refractory to antipsoriatic treatment. Histologically, ILVEN demonstrates abruptly alternating areas of hypergranulosis with orthokeratosis, and parakeratosis with agranulosis. An inflammatory infiltrate is present in the upper dermis. Psoriasis presents with papillomatosis, acanthosis, and parakeratosis with absent or minimal granular layer. Immunohistochemical staining can be done in such doubtful cases. Involucrin would be detectable in psoriasis, but it is absent in ILVEN. Pathogenesis of linear psoriasis is unknown but might be explained by the concept of genetic mosaicism. Although rare, there have been a few reported cases of linear psoriasis occurring in early childhood.

A case of inflammatory linear verrucous epidermal nevus successfully treated with Brodalumab

Inflammatory linear verrucous epidermal nevus (ILVEN) is a rare type of epidermal nevus, commonly arising in childhood. We present a case of a 13-year-old female with Blaschkoid psoriasiform plaques extending from her left foot to the scalp, sparing the right side of the body. While treatment options historically show variable success, we trialed an IL-17a receptor inhibitor as studies have shown increased levels of IL-17 receptor expression in ILVEN keratinocytes. At both 3 and 6 months after treatment initiation there was found to be significant improvement. We propose brodalumab as an effective treatment option for widespread ILVEN.

NSDHL Frameshift Deletion in a Mixed Breed Dog with Progressive Epidermal Nevi

Loss-of-function variants in the NSDHL gene have been associated with epidermal nevi in humans with congenital hemidysplasia, ichthyosiform nevi, and limb defects (CHILD) syndrome and in companion animals. The NSDHL gene codes for the NAD(P)-dependent steroid dehydrogenase-like protein, which is involved in cholesterol biosynthesis. In this study, a female Chihuahua cross with a clinical and histological phenotype consistent with progressive epidermal nevi is presented. All exons of the NSDHL candidate gene were amplified by PCR and analyzed by Sanger sequencing. A heterozygous frameshift variant, c.718_722delGAACA, was identified in the affected dog. In lesional skin, the vast majority of NSDHL transcripts lacked the five deleted bases. The variant is predicted to produce a premature stop codon truncating 34% of the encoded protein, p.Glu240Profs*17. The mutant allele was absent from 22 additionally genotyped Chihuahuas, as well as from 647 control dogs of diverse breeds and eight wolves. The available experimental data together with current knowledge about NSDHL variants and their functional impact in humans, dogs, and other species prompted us to classify this variant as pathogenic according to the ACMG guidelines that were previously established for human sequence variants. Therefore, we propose the c.718_722delGAACA variant as causative variant for the observed skin lesions in this dog.

Widely Spread Unilateral Inflammatory Linear Verrucous Epidermal Nevus (ILVEN)

Inflammatory linear verrucous epidermal nevus (ILVEN) is an epidermal nevus that clinically and histologically mimics linear psoriasis. The pathogenesis of psoriasis has been widely investigated, with recent studies focusing especially on targeting proinflammatory cytokines such as IL-17A, TNFα, IL-23, and IL-12, while little is known about ILVEN. Since the treatment for ILVEN varies widely from the administration of topical ointment for psoriasis to invasive methods such as carbon dioxide gas laser, the differential diagnosis between ILVEN and psoriasis is necessary. In this report, we describe a case of widely spread unilateral ILVEN that clinically and histologically mimicked psoriasis vulgaris and could be diagnosed by immunohistochemical staining focused on the IL-36γ/IL-17A axis.

A Case of "Inflammatory Linear Verrucous Epidermal Nevus" (ILVEN) Treated with CO2 Laser Ablation

The "inflammatory linear verrucous epidermal nevus" is a rare disease, consisting of hyperplasia of the normal components of the epidermis. Its clinical features include erythematous and hyperkeratosic, warty, sometimes psoriasiform or lichenoid patches with a typical linear arrangement. At present, there are no effective medical therapies available. Currently, the best therapeutic results are obtained with surgical excision or the latest laser therapy. The Authors present a 9-years old girl with an inflammatory linear verrucous epidermal nevus on her neck, successfully treated with CO₂ Laser ablation.

Elephantine Psoriasis with Papillomatosis and Alternating Hypogranulosis and Hypergranulosis

Psoriasis is a disease of considerable clinical and histopathological diversity. We report a rare case of elephantine psoriasis responding very well to methotrexate. Histopathology revealed abnormal papillomatosis with finger-like projections in addition to alternating orthokeratosis with overlying hypergranulosis and parakeratosis with overlying hypogranulosis. We believe that this finding may represent an odd histopathologic type in elephantine psoriasis.

Linear psoriasis - a case report

A 56-year-old woman presented with a 3-month history of erythematous plaques covered by scales and limited to the right side of her body. The plaques were arranged along Blaschko's lines with a marked mid-line cutoff. The histopathologic analysis of a skin biopsy in conjunction with the anamnesis allowed the diagnosis of linear psoriasis. Our patient showed a good clinical response to antipsoriatic treatment.