Superficial epidermolytic ichthyosis: A rare disorder with the unusual absence of blistering

Superficial epidermolytic ichthyosis (SEI), formerly known as ichthyosis bullosa of Siemens (IBS), is an extremely rare keratinization disorder with superficial peeling, with an estimated prevalence of 1:500,000, caused by a variety of mutations in the keratin 2E gene. The clinical features include hyperkeratosis and blistering, but these are milder than in epidermolytic hyperkeratosis. The treatment is symptomatic and involves keratolytics and emollients. Herein, we report a case of SEI with the unusual absence of spontaneous blistering.

Recalibrated Scales: The Use of Low-dose Isotretinoin in a Case of Epidermolytic Ichthyosis-NPS1 in a Filipino Child

Epidermolytic Ichthyosis (EI) is a rare non-syndromic keratinopathic ichthyosis without definitive treatment. This is a case of EI in a 5-year-old Filipino female who presented with hyperkeratotic scales sparing the palms and soles. Histopathology revealed epidermolytic hyperkeratosis. A trial of treatment with isotretinoin 0.3 mg/kg/day, together with keratolytic agents, urea lotion and lactic acid lotion, resulted in a marked decrease in the thickness of the scales and odor. Interestingly, rebound effects were noted at 0.6 mg/kg/day. Taking into account that EI presents with more skin fragility compared to non-EHK ichthyosis, the authors surmise that there may be a smaller treatment window for patients with EI, which is notably lower than recommended for ichthyosis in general.

Ichthyosis (concept, pathohistology, clinical picture, treatment)

Ichthyosis is a skin disease that is hereditary, has pronounced symptoms in the form of a violation of the skin, and the presence of formations resembling fish scales. It is possible to distinguish different approaches to the definition of ichthyosis, based on the modern study of this issue. Ichthyosis is classified by type: congenital and acquired. Congenital ichthyosis has its own classification depending on the manifestation of changes in the skin, the course of the disease, concomitant pathologies. Congenital ichthyosis is divided into ordinary (vulgar autosomal dominant, simple) ichthyosis, lamellar ichthyosis (dry ichthyosiform erythroderma, "collodion child", lamellar ichthyosis), X-linked ichthyosis (ichthyosis associated with the X chromosome, blackening ichthyosis), congenital bullous ichthyosiform erythroderma (erythroderma Broca's disease, ichthyosiform epidermolytic hyperkeratosis), fetal ichthyosis (intrauterine ichthyosis, universal hyperkeratosis, "Harlequin fetus", congenital keratosis), other congenital ichthyosis. Ichthyosiform conditions (the so-called acquired ichthyosis) are divided into symptomatic, age-related (senile), discoid ichthyosis. The causes of acquired ichthyosis can be various diseases, taking medications, improper skin care, unbalanced nutrition. Each form of ichthyosis differs by the type of inheritance, prevalence in the population, clinical picture, verified by histological examination of skin biopsies and electron microscopic examination of the skin. It may be accompanied by seasonality of exacerbation of the clinical picture, association with other diseases (allergic, diseases of the gastrointestinal tract, congenital malformations). There is no specific treatment for ichthyosis. In systemic therapy, derivatives of vitamin A are used, keratolytics, as well as moisturizing and emollient agents are used for external treatment. The use of therapeutic baths, general ultraviolet irradiation is effective.

Bilateral Systematised Epidermolytic Epidermal Nevus

Verrucous epidermal nevi (VEN) are benign congenital hamartomas consisting of keratinocytes. Histological examination mostly exhibits hyperkeratosis, acanthosis, papillomatosis and, rarely, the features of epidermolytic hyperkeratosis (EHK). We report a case of a 6-year-old boy who presented at Aga Khan University Hospital, Karachi, Pakistan with bilaterally symmetrical linear epidermal nevi following Blaschko’s lines and showing epidermolytic hyperkeratosis on histology. The patient was treated with topical keratolytics and emolients which led to considerable improvement. To the best of the authors’ knowledge, this is the first report of VEN from Pakistan. KEYWORDS Verrucous Epidermal Nevus; Mosaicism; Epidermolytic Hyperkeratoses; Hamartoma; Case Report; Pakistan.

First Case of KRT2 Epidermolytic Nevus and Novel Clinical and Genetic Findings in 26 Italian Patients with Keratinopathic Ichthyoses

Keratinopathic ichthyoses (KI) are a clinically heterogeneous group of keratinization disorders due to mutations in KRT1, KTR10, or KRT2 genes encoding keratins of suprabasal epidermis. Characteristic clinical features include superficial blisters and erosions in infancy and progressive development of hyperkeratosis. Histopathology shows epidermolytic hyperkeratosis. We describe the clinical, histopathological, and molecular findings of a series of 26 Italian patients from 19 unrelated families affected with (i) epidermolytic ichthyosis due to KRT1 or KRT10 mutations (7 and 9 cases, respectively); (ii) KTR10-mutated ichthyosis with confetti (2 cases); (iii) KRT2-mutated superficial epidermolytic ichthyosis (5 cases); and (iv) KRT10-mutated epidermolytic nevus (2 cases). Of note, molecular genetic testing in a third case of extensive epidermolytic nevus revealed a somatic missense mutation (p.Asn186Asp) in the KRT2 gene, detected in DNA from lesional skin at an allelic frequency of 25% and, at very low frequency (1.5%), also in blood. Finally, we report three novel dominant mutations, including a frameshift mutation altering the C-terminal V2 domain of keratin 1 in three familiar cases presenting a mild phenotype. Overall, our findings expand the phenotypic and molecular spectrum of KI and show for the first time that epidermolytic nevus can be due to somatic KRT2 mutation.