Netherton Syndrome Research Articles

Developing a core outcome set for Netherton syndrome: An international multi-stakeholder e-Delphi consensus study.

Netherton syndrome (NS; OMIM#256500) is a rare and severe disorder of epidermal maturation and keratinization caused by pathogenic variants in the serine protease inhibitor Kazal type 5 (SPINK5), leading to severe skin barrier impairment. Although effective treatment is crucial for NS patients, there is a lack of knowledge on what the best treatment options are for these patients. Large heterogeneity in reported outcomes and measurement instruments hinders accurate comparison of treatment results across studies and the development of a treatment guideline. Therefore, we aimed to develop a core outcome set (COS) for NS that can be used in clinical care and research. This study was performed in accordance with the recommendations of the Core Outcome Measures in Effectiveness Trials (COMET) initiative. After identification of outcomes through a literature search and classification based on the International Classification of Functioning and taxonomies published by the COMET initiative, discussion groups were organized at the 2nd International Netherton Congress 2022 to finalize the provisional outcome list. Through a 2-round e-Delphi, 41 stakeholders (patients and family members, professionals, and representatives of industry) from 14 countries rated the importance of the outcomes using a 9-point Likert scale. An online consensus meeting attended by 14 stakeholders finalized the COS. The core outcome set for NS comprised 21 outcomes in 10 domains. These included four 'skin' outcomes, two 'sensation' outcomes, two 'side-effects of treatment' outcomes, one 'vitality' outcome, one 'emotional functioning' outcome, two 'physical development' outcomes, two 'nutrition' outcomes, two 'infections' outcomes, two 'allergies' outcomes, and three 'assessment results' outcomes. In this study, consensus was reached on 21 outcomes to be included in the COS for NS. The selection of outcomes in the COS underlines that NS not only affects the skin, but is a disease requiring a broad multidisciplinary approach in clinical care and research. International implementation of this COS will lead to more uniform reporting, thereby enabling comparison of study results, which may facilitate future treatment guideline development. The next step is to further conceptually define the outcomes and reach consensus on how the measure these.

Polysaccharide, Conjugate, and mRNA-based Vaccines are Immunogenic in Patients with Netherton Syndrome

BackgroundNetherton syndrome (NS) is a rare, severe genetic skin disorder, currently classified as an inborn error of immunity (IEI) due to previously reported immune dysregulation. We recently reported the results of an immunological evaluation showing no evidence for a relevant B- and/or T-cell mediated immunodeficiency, but immune responses after vaccination were not evaluated in that study. Therefore, we evaluated immune responses to three vaccine platforms in adult NS patients to further investigate the presence of a clinically relevant B- and/or T-cell immunodeficiency.MethodsVaccination responses in eight adult NS patients were assessed in a cross-sectional study performed between January and August 2022. Clinical patient data were retrospectively retrieved from electronic patient files. Immune responses to a polysaccharide Streptococcus pneumoniae vaccine (PPV23) and conjugate Haemophilus influenzae type b vaccine (ActHiB) were measured. SARS-CoV-2-specific (functional) antibody and T-cell responses following booster vaccination with an mRNA-based COVID-19 vaccine were compared to controls.ResultsNone of the included patients suffered from recurrent and/or severe infections that could be attributed to a B- and/or T-cell immunodeficiency. ActHiB induced immune responses were normal in 7/7 NS patients. PPV23 induced responses were absent in 1/7, diminished in 2/7, and normal in 4/7 patients. Levels of SARS-CoV-2-specific binding and neutralizing antibodies after mRNA-based COVID-19 booster vaccination in NS patients were comparable to controls. SARS-CoV-2-specific CD4 + T-cell responses were detectable in all NS patients. In contrast, SARS-CoV-2-specific CD8 + T-cell responses were detectable in only 2/6 NS patients. T-cell responses to a positive control antigen pool were comparable to controls.ConclusionsVaccine-induced immune responses were detectable after polysaccharide, conjugate and mRNA-based vaccination in our cohort of NS patients. A spectrum of responsiveness to vaccine challenges was found, with the ranges of vaccine responses overlapping those demonstrated in healthy control populations.

Biologics in congenital ichthyosis: are they effective?

Congenital ichthyoses (CI) comprise a heterogeneous group of genetic diseases requiring lifelong treatment and having a major effect on quality of life. Conventional treatments reduce scaling and skin discomfort; however, they usually have little or no effect on erythema and pruritus. The identification of cytokine alterations in CI raised the possibility of repurposing available biologics. Several case reports in the literature report successes using different biologics. We aimed to report the effects of biologics in real life. This was a retrospective, observational, international multicenter study of patients with CI treated with at least one biologic for a minimum of 3 months. The effect of the biologics was evaluated using an Investigator Global Assessment-Change (IGA-C) scale. A comprehensive literature search was performed in parallel. A total of 98 patients were included, with a mean age of 19.7 years and both sexes equally represented. Patients with Netherton syndrome (NS) or congenital ichthyosiform erythroderma (CIE) represented the majority of patients (30% and 21.4%, respectively). Most patients (84.7%) had a severe or very severe form of CI. The most frequently used biologics were inhibitors targeting interleukin-17 (IL-17), IL-12/IL-23, or the IL-4 receptor. The mean duration of treatment was 22+20.1 months. There were 45 responders (45.9%), including 18 patients (18.3%) who were good responders; all had an erythrodermic CI subset and received one of the three main biologics. In 2 NS and CIE, IL-12/IL-23 and IL-4 receptor inhibitors tended to be most effective. Review of the literature revealed a shorter mean duration of use of biologics (11.5+8.5 months) and higher percentage of responders (85.7%), suggesting reporter bias. This series identified subsets of CI that may respond to biologics and will aid in designing future clinical trials of biologics for CI.

Spesolimab, the first-in-class anti-IL-36R antibody: From bench to clinic.

Inflammatory diseases that are driven by several pro-inflammatory cytokines has resulted in in the development of targeted therapies across different disease settings. Interleukin (IL)-36 cytokines have been implicated in several inflammatory diseases. In this review we describe the scientific evidence surrounding the use of the IL-36 receptor (IL-36R)-targeting antibody, spesolimab, in IL-36-mediated skin diseases: generalized pustular psoriasis (GPP), palmoplantar pustulosis (PPP), hidradenitis suppurativa, and Netherton syndrome (NS). Spesolimab, a high affinity, specific, humanized, antagonistic immunoglobulin G1 antibody, targets the IL-36R at a binding site distinct from its agonists, IL-36α/β/γ, and at least one endogenous antagonist, IL-36R antagonist. Invitro and invivo data for spesolimab show effective inhibition of IL-36R-mediated signaling pathways, and six Phase I studies in healthy volunteers presented a favorable safety and pharmacokinetic (PK) profile, leading to the development of a clinical trial program to evaluate spesolimab in the treatment of IL-36R-mediated diseases. Six studies (including an expanded access program) have evaluated the efficacy, safety, PKs, and pharmacogenomics of spesolimab in patients with GPP flares. Spesolimab treatment of GPP flares resulted in rapid and sustained improvements in pustular and skin clearance, and clinically significant improvements in patient-reported symptoms and quality of life. Spesolimab also significantly reduces the risk of GPP flares and flare occurrence, preventing disease worsening and has a favorable safety profile. There have been three trials of spesolimab in PPP; further evaluation is needed to better define those patients who might benefit from the treatment. A trial of spesolimab in NS is ongoing, while other spesolimab trials suggest that IL-36 may only play a secondary role in the pathogenesis of atopic dermatitis. In conclusion, research into spesolimab has provided much needed insight into the role of IL-36 in the human immune system and the mechanism behind IL-36-mediated inflammatory diseases. Spesolimab provides an efficacious targeted treatment for GPP, a disease with a high unmet medical need.

Upadacitinib shows efficacy in Netherton syndrome with poor response to Dupilumab

Upadacitinib shows efficacy in Netherton syndrome with poor response to Dupilumab

Strategies for Differential Diagnosis and Management of Ichthyosis in Newborns

Congenital ichthyosis represents agroup of heterogeneous inherited skin diseases characterized by generalized keratinization disorder in the form of hyperkeratosis, caused by abnormalities in epidermal differentiation. The neonatal period is crucial for patients with ichthyosis due to the risk of developing complications, comorbidities, and fatal outcomes. Most complications arise from impaired skin barrier function. This article discusses the manifestations of ichthyosis in newborns, describes risks and complications, and suggests strategies for monitoring and treating patients. Purpose of the study: to present contemporary data on differential diagnosis and treatment strategies for newborn patients with congenital ichthyosis. Materials and Methods: review of Russian and international sources dedicated to the etiology, diagnosis, and treatment of ichthyosis was conducted. Results: Differential diagnosis of ichthyosis in the neonatal period is acrucial task, hence the most life-threatening subtypes are considered. The most severe progression with ahigh risk of fatal outcomes is characteristic of Harlequin ichthyosis. Collodion baby presents with less pronounced symptoms, is not afinal diagnosis, and may later develop clinical manifestations typical of ichthyosiform erythroderma, lamellar ichthyosis, or self-resolving congenital ichthyosis. Netherton syndrome is characterized by acombination of congenital ichthyosis with structural abnormalities of the hair shaft and apropensity for atopy. Epidermolytic ichthyosis, accompanied by the formation of blisters and erosions on the skin, requires differential diagnosis not only with other forms of ichthyosis but also with bullous epidermolysis, staphylococcal scalded skin syndrome, and toxic epidermal necrolysis. Every newborn with described manifestations requires support from amultidisciplinary team of specialists and timely therapeutic and diagnostic measures aimed at preventing the development of complications and deterioration of the patient’s condition. Conclusion: An analysis of global literature data and the practical experience of the authors indicate the complexities of differential diagnosis of ichthyosis forms in the neonatal period. To improve skin condition, prevent infectious complications, and correct electrolyte and respiratory disturbances, symptomatic treatment should begin before adefinitive diagnosis is established.

A combination therapy with secukinumab and dupilumab in Netherton syndrome: A prospective pilot study

A combination therapy with secukinumab and dupilumab in Netherton syndrome: A prospective pilot study

52665 The burden of Netherton syndrome and interest in biologics: A qualitative summary of patient and caregiver interview responses

52665 The burden of Netherton syndrome and interest in biologics: A qualitative summary of patient and caregiver interview responses

Staphylococcus aureus Proteases: Orchestrators of Skin Inflammation.

Skin homeostasis relies on a delicate balance between host proteases and protease inhibitors along with those secreted from microbial communities, as disruption to this harmony contributes to the pathogenesis of inflammatory skin disorders, including atopic dermatitis and Netherton's syndrome. In addition to being a prominent cause of skin and soft tissue infections, the gram-positive bacterium Staphylococcus aureus is a key player in inflammatory skin conditions due to its array of 10 secreted proteases. Herein we review how S. aureus proteases augment the development of inflammation in skin disorders. These mechanisms include degradation of skin barrier integrity, immune dysregulation and pruritis, and impairment of host defenses. Delineating the diverse roles of S. aureus proteases has the potential to reveal novel therapeutic strategies, such as inhibitors of proteases or their cognate target, as well as neutralizing vaccines to alleviate the burden of inflammatory skin disorders in patients.

Recombinant scFv-Fc Anti-kallikrein 7 Antibody-Loaded Thermosensitive Hydrogels Against Skin Desquamation Disorders.

Human tissue kallikrein-related peptidase 7 (KLK7) is a serine protease implicated in the physiology of skin desquamation, and its uncontrolled activity can lead to chronic diseases such as psoriasis, atopic dermatitis, and Netherton syndrome. For this reason, kallikrein 7 has been identified as a potential therapeutic target. This work aimed to evaluate Pluronic (PL) hydrogels as topical carriers of four specific scFv-Fc antibodies to inhibit KLK7. The hydrogels comprised PL F127 (30% w/v) alone and a binary F127/P123 (28-2% w/v) system. Each formulation was loaded with 1 μg/mL of each antibody and characterized by physicochemical and pharmaceutical techniques, considering antibody-micelle interactions and hydrogel behavior as smart delivery systems. Results showed that the antibodies were successfully loaded into the PL-based systems, and the sol-gel transition temperature was shifted to high values after the P123 addition. The antibodies released from the gels preserved their rheological properties (G' > G'', 35- to 41-fold) and inhibitory activity against KLK7, even after 24 h. This work presented potential agents targeting KLK7 that may provide strategies for treating skin abnormalities.

The role of interleukin-36 in health and disease states.

The interleukin (IL)-1 superfamily upregulates immune responses and maintains homeostasis between the innate and adaptive immune systems. Within the IL-1 superfamily, IL-36 plays a pivotal role in both innate and adaptive immune responses. Of the four IL-36 isoforms, three have agonist activity (IL-36α, IL-36β, IL-36γ) and the fourth has antagonist activity (IL-36 receptor antagonist [IL-36Ra]). All IL-36 isoforms bind to the IL-36 receptor (IL-36R). Binding of IL-36α/β/γ to the IL-36R recruits the IL-1 receptor accessory protein (IL-1RAcP) and activates downstream signalling pathways mediated by nuclear transcription factor kappa B and mitogen-activated protein kinase signalling pathways. Antagonist binding of IL-36Ra to IL-36R inhibits recruitment of IL-1RAcP, blocking downstream signalling pathways. Changes in the balance within the IL-36 cytokine family can lead to uncontrolled inflammatory responses throughout the body. As such, IL-36 has been implicated in numerous inflammatory diseases, notably a type of pustular psoriasis called generalized pustular psoriasis (GPP), a chronic, rare, potentially life-threatening, multisystemic skin disease characterised by recurrent fever and extensive sterile pustules. In GPP, IL-36 is central to disease pathogenesis, and the prevention of IL-36-mediated signalling can improve clinical outcomes. In this review, we summarize the literature describing the biological functions of the IL-36 pathway. We also consider the evidence for uncontrolled activation of the IL-36 pathway in a wide range of skin (e.g., plaque psoriasis, pustular psoriasis, hidradenitis suppurativa, acne, Netherton syndrome, atopic dermatitis and pyoderma gangrenosum), lung (e.g., idiopathic pulmonary fibrosis), gut (e.g., intestinal fibrosis, inflammatory bowel disease and Hirschsprung's disease), kidney (e.g., renal tubulointerstitial lesions) and infectious diseases caused by a variety of pathogens (e.g., COVID-19; Mycobacterium tuberculosis, Pseudomonas aeruginosa, Streptococcus pneumoniae infections), as well as in cancer. We also consider how targeting the IL-36 signalling pathway could be used in treating inflammatory disease states.

Netherton Syndrome: Diagnosis made easy with Trichoscopy

Netherton Syndrome: Diagnosis made easy with Trichoscopy

Clinical Spectrum of Congenital Ichthyosis in Pediatric Age Group from a Tertiary Care Center in India

Objective: Ichthyosis is a disorder of cornification, which can be acquired or inherited, and encompasses various forms of generalized scaling and superficial roughness of the skin secondary to impaired skin barrier. It can be often associated with systemic manifestations. There is a paucity of Indian studies assessing the clinical and demographic profile of children with inherited ichthyosis. Hence, we conducted this study with the primary objective of assessing the clinical and epidemiological profile of children with congenital ichthyosis (CI). Materials and Methods: The study was conducted over 1 year. All children aged up to 18 years of age, with the clinical diagnosis of CI, were evaluated for epidemiological profile and clinical features. Results: A total of 32 children with CI presented with a mean age of 6 ± 4.81 years. The most common phenotype was ichthyosis vulgaris, seen in 13 (40.6%) children, while X-linked recessive ichthyosis was present in 6 (18.75%) children. Epidermolytic ichthyosis (EI) was also seen in 6 (18.75%) children, out of which 5 were diagnosed with generalized EI and 1 was diagnosed with superficial EI. Lamellar ichthyosis was seen in 4 (12.5%) children. Sjogren–Larsson syndrome (SLS), harlequin ichthyosis, and Netherton syndrome were present in 1 (3.1%) case each. Various extracutaneous abnormalities detected were ectropion (9.3%), lagophthalmos (3.1%), and refractive error with stye (3.1%) on ophthalmological evaluation, gross development delay (8.75%), and neurological involvement in the form of spastic quadriplegia (one patient with SLS). Conclusions: CI comprises various skin diseases and can range from mild to very severe presentation with systemic involvement. Identification of the phenotypic expression of ichthyosis is a prerequisite for making prognostic predictions, therapeutic decisions, and offering genetic counseling.

Development of a back-titration assay to quantitate functional lympho-epithelial Kazal-type inhibitors (LEKTI) in skin samples

The lympho-epithelial Kazal-type inhibitors (LEKTI) are key to control skin turnover, and their absence causes Netherton syndrome. For clinical sample testing of LEKTI-based therapies, a robust analytical method to measure LEKTI-like activity in skin is required. This work reports on the development of a back-titration method to determine incremental LEKTI-like activity in skin samples. The method meets the analytical requirements for study sample testing, and reliable quantification can be achieved with negligible skin matrix interference. This assay does not provide analyte identity, but it can be used to measure treatment-driven increments of LEKTI-like activity within the skin epidermis.

Personal, financial and time burden in inherited ichthyoses: Asurvey of 144 patients in a university-based setting.

Patients with inherited ichthyosis suffer from scaling due to mutations affecting the epidermal barrier. Symptomatic treatment with ointments, bathing and mechanical scale removal can alleviate the disease, but therapy is time and cost intensive. We investigated costs, time and disease burden of ichthyoses. The study addresses difficulties of the healthcare situation for patients with ichthyoses and reveals potential improvements. We developed a questionnaire addressing time and financial effort for the treatment. Additionally, we collected data of the Dermatology Life Quality Index (DLQI) and the Pruritus Life Quality (5PLQ) questionnaires to determine the impact of ichthyosis and associated pruritus on quality of life (QoL). We recruited 144 patients with ichthyosis (median age: 23; 53.5% female) from the Department of Dermatology in Muenster (Germany) and the German patient support group including common, rare and syndromic subtypes. Eighty-seven percent reported applying topical therapeutics at least once per day, 66.4% several times with an overall median duration of 15 min. Highest single expenditure of time was due to balneotherapy (n = 115; median bathing time: 40 min). In 81.9%, the health insurance did not completely cover the costs for topical treatment causing additional financial burden to the patient with a median of 71 € per quarter, herein creams being the largest cost factor (50 €). Patients with Netherton syndrome showed the highest median expenditure (170 €). The QoL impairment under treatment was moderate (median DLQI: 8.5 points). Pruritus was prevalent in 79.9% and showed a distinct impact on QoL (median 5PLQ: 7.5 points) without any significant difference between the subtypes (p = 0.37). Patients suffering from ichthyoses have a large and lifelong overall burden in mild and severe subtypes. Since continuous topical treatment is required, financial and psychosocial support needs to be considered beyond dermatological care.

Genetic inheritance in tandem: Non-syndromic autosomal recessive congenital ichthyosis with beta-thalassaemia: A rare coincidence

Ichthyosis belongs to the group of Mendelian disorders of cornification. Congenital ichthyosis is inherited as an autosomal recessive trait, so it is also known as autosomal recessive congenital ichthyosis (ARCI). ARCI is classified into two types: syndromic and non-syndromic ARCI. Non-syndromic ARCIs include lamellar ichthyosis, congenital ichthyosiform erythroderma and Harlequin ichthyosis. Syndromic-ARCI is associated with multisystemic involvement, which includes Netherton syndrome, Chanarin-Dorfman disease and others. Other systemic diseases associated with ichthyosis include Gaucher disease type II and hypothyroidism. Chanarin-Dorfman and Gaucher disease-II are additionally associated with hepatosplenomegaly (HSM) and anaemia. We describe a child of congenital ichthyosis with HSM and anaemia thought to be syndromic-ARCI, but diagnosed for beta-thalassaemia (b-thal) concurrently. An infant presented with peeling skin along with absent sweating since birth and recent onset paleness of the body. Examination revealed Ichthyosis (Lamellar-variant), severe pallor and HSM, raising the possibility of Chanarin-Dorfman syndrome and Gaucher’s disease. The investigation revealed an Erlenmeyer flask deformity of the knee, but no Gaucher’s cells were found in the bone marrow. In the absence of lipid vacuoles leaden leukocytes (Jordan’s anomaly), Chanarin-Dorfman disease was also ruled out. Haemoglobin (Hb) high-performance liquid chromatography revealed β-thal major, and both parents were traits, giving us the diagnosis, which was further confirmed by the next-generation gene sequencing for clinical exomes. This report was to highlight non-syndromic ARCI involving the CYP4F22 gene variant, which is a rare finding, and the association of such ichthyosis with β-thal major was an unexpected result. Genetic counselling was provided to the parents in light of the autosomal recessive nature of both diseases. Genes of congenital ichthyosis and β-thal were unrelated, but simultaneous expressions of two autosomal-recessive diseases together are it merely by chance or a new entity.

Erythrokeratodermia Variabilis-like Phenotype in Patients Carrying ABCA12 Mutations.

Erythrokeratodermia variabilis (EKV) is a rare genodermatosis characterized by well-demarcated erythematous patches and hyperkeratotic plaques. EKV is most often transmitted in an autosomal dominant manner. Until recently, only mutations in connexins such as GJB3 (connexin 31), GJB4 (connexin 30.3), and occasionally GJA1 (connexin 43) were known to cause EKV. In recent years, mutations in other genes have been described as rare causes of EKV, including the genes KDSR, KRT83, and TRPM4. Features of the EKV phenotype can also appear with other genodermatoses: for example, in Netherton syndrome, which hampers correct diagnosis. However, in autosomal recessive congenital ichthyosis (ARCI), an EKV phenotype has rarely been described. Here, we report on seven patients who clinically show a clear EKV phenotype, but in whom molecular genetic analysis revealed biallelic mutations in ABCA12, which is why the patients are classified in the ARCI group. Our study indicates that ARCI should be considered as a differential diagnosis in EKV.

Comparative analyses of Netherton syndrome patients and Spink5 conditional knock-out mice uncover disease-relevant pathways

Netherton syndrome (NS) is a rare skin disease caused by loss-of-function mutations in the serine peptidase inhibitor Kazal type 5 (SPINK5) gene. Disease severity and the lack of efficacious treatments call for a better understanding of NS mechanisms. Here we describe a novel and viable, Spink5 conditional knock-out (cKO) mouse model, allowing to study NS progression. By combining transcriptomics and proteomics, we determine a disease molecular profile common to mouse models and NS patients. Spink5 cKO mice and NS patients share skin barrier and inflammation signatures defined by up-regulation and increased activity of proteases, IL-17, IL-36, and IL-20 family cytokine signaling. Systemic inflammation in Spink5 cKO mice correlates with disease severity and is associated with thymic atrophy and enlargement of lymph nodes and spleen. This systemic inflammation phenotype is marked by neutrophils and IL-17/IL-22 signaling, does not involve primary T cell immunodeficiency and is independent of bacterial infection. By comparing skin transcriptomes and proteomes, we uncover several putative substrates of tissue kallikrein-related proteases (KLKs), demonstrating that KLKs can proteolytically regulate IL-36 pro-inflammatory cytokines. Our study thus provides a conserved molecular framework for NS and reveals a KLK/IL-36 signaling axis, adding new insights into the disease mechanisms and therapeutic targets.

Staphylococcus aureus proteases trigger eosinophil-mediated skin inflammation

Staphylococcus aureus skin colonization and eosinophil infiltration are associated with many inflammatory skin disorders, including atopic dermatitis, bullous pemphigoid, Netherton's syndrome, and prurigo nodularis. However, whether there is a relationship between S. aureus and eosinophils and how this interaction influences skin inflammation is largely undefined. We show in a preclinical mouse model that S. aureus epicutaneous exposure induced eosinophil-recruiting chemokines and eosinophil infiltration into the skin. Remarkably, we found that eosinophils had a comparable contribution to the skin inflammation as T cells, in a manner dependent on eosinophil-derived IL-17A and IL-17F production. Importantly, IL-36R signaling induced CCL7-mediated eosinophil recruitment to the inflamed skin. Last, S. aureus proteases induced IL-36α expression in keratinocytes, which promoted infiltration of IL-17-producing eosinophils. Collectively, we uncovered a mechanism for S. aureus proteases to trigger eosinophil-mediated skin inflammation, which has implications in the pathogenesis of inflammatory skin diseases.

Photogallery. Genodermatoses. Part II

Genodermatoses are a group of hereditary diseases primarily affecting the skin. To date, there are more than two hundred genetically determined dermatoses representing about 35% of all genetic diseases and 10% of all skin diseases. Genodermatoses can be caused by mutations in a single gene or the interaction of several genes and environmental factors. Hereditary diseases are characterized by a wide variety of phenotypic manifestations and the diagnostic complexity which represents a serious problem in modern dermatology.
 We present a gallery of hereditary dermatoses.
 Unna-Tost disease is a genodermatosis inherited in an autosomal dominant manner and characterized by diffuse excessive keratinization of the skin on the palms and soles, manifesting in the first to second year of life.
 Buschke-Fischer-Brauer punctate palmoplantar keratoderma is a late-developing focal dermatosis in which painful hyperkeratotic papules can occur when traumatized.
 Ehlers-Danlos syndrome is a condition demonstrating skin hyperextensibility and a number of typical symptoms of the skeletal and cardiovascular systems.
 Progeria manifests as premature skin aging, affecting the endocrine, skeletal, cardiovascular, and other systems of the body, as well as increasing the risk of developing malignant neoplasms of internal organs and skin.
 Congenital ichthyosiform erythroderma of Brocq is a severe chronic skin disease with autosomal recessive inheritance, which follows the pattern of lamellar ichthyosis but to a milder degree.
 X-linked ichthyosis, a hereditary "darkening" condition, occurs only in males and is characterized by impaired keratinization and the presence of gray-black scales on the skin.
 Lamellar ichthyosis is an autosomal recessive dermatosis characterized by generalized skin involvement.
 Netherton syndrome is a rare condition characterized by a combination of ichthyosis with structural anomalies of the hair shaft and atopy.